Cell suspensions

Hum Genet, 1980, 53(3), 327 - 33
{Preliminary study of stages of human meiosis in spermatocytes and ovocytes (author's transl)}; Geneix A et al.; Human meiotic chromosomes, from spermatocytes and ovocytes, are described after observations of whole mount preparations under E.M . Small testicular and ovarian fragments are put in distillated water, then macerated; the cell suspension is spread on the surface of sheet copper grids covered with formvar plus collodion films . After dehydratation interesting stages are selected under L.M . before observations under E.M . Zygotene and pachytene are the most common stages . During pachytene the chromomeres are well individualized; the synaptonemal complex may be observed; chromatin fibers connect the chromosomes to nuclear pores, interchromosomal fibers joint the bivalents . Zygotene and pachytene bivalents are very similar in the male and the feminine germ cells.

Biofizika, 1980 Jan-Feb, 25(1), 178 - 80
{Nature of the membrane potential of liver cells}; Malenkov AG et al.; Light scattering (90 degrees) of Ehrlich ascites tumor and sarcoma 37 cell suspension in the temperature range 25,60 degrees C was studied (heating velocity was 3 grad/min) . It is found that the scattering curve has the peak at 46 degrees C and two plots which are typical of phase transitions in the membranes; the first plot in the range 40-46 degrees C is reversible and the second one at 46-51 degrees C is irreversible . It is proposed that 46 degrees is a critical temperature for the membranes structure stability and viability of the studied cells.

Biofizika, 1980 Jan-Feb, 25(1), 177 - 8
{Temperature phase transitions in cancer cells}; Popov GA et al.; Light scattering (90 degrees) of Ehrlich ascites tumor and sarcoma 37 cell suspension in the temperature range 25-60 degrees C was studied (heating velocity was 3 grad/min) . It is found that the scattering curve has the peak at 46 degrees C and two plots which are typical of phase transitions in the membranes; the first plot in the range 40-46 degrees C is reversible and the second one at 46-51 degrees C is irreversible . It is proposed that 46 degrees is a critical temperature for the membranes structure stability and viability of the studied cells.

Eur J Biochem, 1980 Jan, 103(2), 323 - 30
Messenger RNA coding for phenylalanine ammonia-lyase . Characterization and partial purification from cell suspension cultures of Petroselinum hortense; Ragg H et al.; The mRNA coding for phenylalanine ammonia-lyase was partially purified from irradiated cell suspension cultures of parsley (Petroselinum hortense) . The product of cell-free translation of the mRNA in a reticulocyte lysate was isolated by immunoprecipitation and compared with the native enzyme subunit . Evidence for the identity, or at least a great similarity, of both was provided by tryptic-peptide and gel-electrophoretic analyses . Under partially denaturing conditions, phenylalanine ammonia-lyase mRNA sedimented as a 20--21-S molecule in a sucrose gradient and had an apparent molecular weight of about 1.05 x 10(6) on a polyacrylamide gel . Approximately two-thirds of the polynucleotide sequence of the mRNA were estimated to be required as coding sequence for the enzyme . We suggest that phenylalanine ammonia-lyase mRNA is unlikely to code for more than of three coordinately induced enzymes.

J Surg Oncol, 1980, 13(1), 39 - 44
Mouse colostomy model for studies on large bowel cancer; Volenec FJ et al.; The development of appropriate animal model systems has been proposed as a means of facilitating the study of human colorectal cancer . This report describes the development and use of a blind-colorectal pouch in a carcinoma mouse model . The blind-pouch was prepared in C57BL/6J mice by surgically exteriorizing the descending colon and producing two stomata in the abdominal wall . The proximal stoma served as an end colostomy and the distal stoma created as a mucous fistula . Surgical closure of the anus thus provided a colorectal pouch . In pilot studies it was found that N-methyl-N-nitrosourea (MNU) and radiation together but neither separately produced tumors in the pouch of surviving mice . Further, inoculation of C38 syngeneic tumor cell suspension into the pouch and immediate closure resulted in tumor takes within three to four weeks . The use of this model in carcinogenesis and the immunology of colon cancer simulate the human colorectal cancer problem more closely than previous animal models.

Paroi Arterielle, 1980, 6(4), 207 - 11
{Expression of results in studies of vascular biochemical components during the development of the SHR rat}; Bucher B et al.; Hypertrophy and hyperplasia induced by age and hypertension as well as tissue heterogeneity makes it difficult to analyse biochemical datas obtained with rats thoracic aortas from rats of various age and blood pressure . In SHR, the thoracic aorta weight increases parallely to the body weight from the first week after birth onwards . Meanwhile the protein content of the organ increases parallely to the organ weight . However, though the DNA content increases markedly up to 7 weeks of age, one observes a much lower increase with age afterwards . It seemed to us that the aorta DNA content was more representative of the organ cell number . This led us to use express our biochemical data per mg of the organ DNA content . Moreover, it seems necessary to take in account the cell volume which increases as well with age and hypertension on the one hand, and to be able to distinguish the cellular content of the myocytes from the one of other cells types contained in the adventitia and the intima, on the other hand . For these purposes pure media layers are prepared by completely removing the adventitia and intima and single cell suspensions are obtained after total enzyme digestion of the medias.

Beitr Trop Landwirtsch Veterinarmed, 1980, 18(4), 395 - 8
Karyological study of Gallus domesticus macrochromosomes; El-Metainy AY et al.; After an incubation period of four days and colchicine pretreatment (air-cell method), clear metaphase figures were obtained from a cell suspension of the allantoic sacs . It was only by shortening the colchicine application to one hour that sufficiently elongated chromosomes suitable for karyological studies could be prepared . The total arm length and the arm length indices are given of the six pairs of macrochromosomes - including the Z chromosome - and of the three largest microchromosomes . Different from the previous findings as reported in the literature, the two largest macrochromosomes are described as submetacentric and not as metacentric . The findings on the seven chromosomes following agree with those given in the literature.

Recent Results Cancer Res, 1980, 75, 252 - 9
Erythrocytes and lymphocytes as drug carrier systems: techniques for entrapment of drugs in living cells; Zimmermann U et al.; Mouse thymocytes and erythrocytes are loaded electrically with drugs in isotonic solution . The loaded cells are used for targeting the drugs to specific sites in the organism in order to achieve a controlled drug release in time and space . The field technique used for the loading of the cells is based on the dielectric breakdown of the cell membrane which is observed when cell suspensions are subjected to external field pulses of 2-20 kV/cm for short time intervals (ns to microseconds) . When an apparent membrane potential of about 1 V is reached in response to the external field, the membrane breaks down reversibly . The breakdown of the membrane is associated with a remarkable and reversible permeability increase of the cell membrane . The increase in permeability depends on the strength and the duration of the field pulse.

Arch Dermatol Res, 1980, 268(3), 231 - 7
Increased "in vivo" lymphocyte blastogenesis in the peripheral blood of patients with atopic dermatitis and allergic contact dermatitis; Lachapelle JM et al.; The spontaneous 3H-thymidine (3HT) labelling of some lymphocyte subpopulations has been studied in the peripheral blood of five patients with atopic dermatitis and five with widespread allergic contact dermatitis and compared with that in 10 healthy subjects . One hour after addition of 3HT to heparinized blood, lymphocytes were separated and processed with two different rosetting techniques (E-rosette test and Active E-rosette test) . The cell suspensions were cytocentrifugated and autoradiography undertaken . An increased number of 3HT labelled lymphocytes was observed in the peripheral blood of patients with dermatitis as compared to controls . These labelled lymphocytes were E-rosette-forming cells (T cells) and E-non-rosette-forming cells (non-rosette-forming T cells and non-T cells) . The ratio between the labelling index (LI) of E-rosette- to the LI of non-E-rosette-forming cells was in favour of T cells in allergic contact dermatitis (ratio = 3.09) whereas in atopic dermatitis (ratio = 0.93) the DNA synthesis was relatively greater in the non-rosette-forming cells . It is suggested that this increased LI of peripheral blood lymphocytes could be related to the increased derman mononuclear cell 3HT-labelling that has been reported previously in these inflammatory skin diseases.

J Immunol Methods, 1980, 35(1-2), 43 - 56
An anti-human t-lymphocyte antiserum . Further characterization of the specificity for T-cell subpopulations and a comparison of methods for identification of T-lymphocytes in tissue sections; Braathen LR; An anti-human T-lymphocyte antiserum has been further studied for specificity for T-cell subpopulations and application in tissue sections . Using a complement-dependent microcytotoxicity assay about 60% of normal peripheral blood T-cells were found to be sensitive to lysis, while 40% were resistant . When the T-cell suspensions were depleted of TG-cells using EA (Ripley) rosette sedimentation, the remaining cells demonstrated an increased percentage of lysis-sensitive cells, while the T-cells enriched in EA-RFC demonstrated a decreased percentage of cells sensitive to lysis, indicating that the antiserum was primarily directed against the non TG-cells, i.e . probably the TM helper cell population . This was further supported by functional studies . In order to quantitate T-cells, cytocentrifuge preparations were made from cell suspensions with known T-cell percentages and the T-cells determined with both the immune adherence technique using AET-treated sheep erythrocytes, as well as the indirect immunofluorescence technique using anti-T antiserum . The results of the two methods correlated well, suggesting that both methods can be used to determine T-cells in situ in infiltrate-like clusters of cells.

J Immunol Methods, 1980, 37(3-4), 275 - 86
The intracellular localisation of immunoglobulin in human lymphoid cells and haematopoietic cell lines by immunoperoxidase electron microscopy; Newell DG et al.; A technique is described for the ultrastructural localisation of intracellular immunoglobulin (Ig) in human lymphoid cell suspensions by the immunoperoxidase method . The technique involves restricted saponin digestion of glutaraldehyde prefixed cells to enhance conjugate penetration . With this method of staining Ig was located in the rough endoplasmic reticulum, perinuclear space and Golgi apparatus in human lymphoid cells from a variety of sources, which is consistent with previously published observations using other ultrastructural techniques . In contrast, diffuse intracytoplasmic staining was predominant in cells prefixed with glutaraldehyde but not treated with saponin . These differences in patterns are discussed in terms of membrane permeability . Although saponin treatment was necessary for consistent localisation of intracellular Ig it resulted in unavoidable loss of Ig from the surface of the cells.

Folia Microbiol (Praha), 1980, 25(5), 361 - 8
Characterization of adenylate cyclase from Escherichia coli; Janecek J et al.; Adenylate cyclase activity was detected and characterized in cell-free preparations of different strains of Escherichia coli; it was localized not only in the membrane fraction but also in the cytoplasm, the localization differing from strain to strain . The adenylate cyclase activity is highly dependent on the method used for disintegration of cells . The best results were obtained when using vortexing of the cell suspension with ballotini beads . The pH optimum of adenylate cyclase in cell-free preparations was found to be 9.0--9.5 . The enzyme has an absolute requirement for Mg2+ and is inhibited by sodium fluoride and inorganic diphosphate . Release of adenylate cyclase from the membrane leads to an immediate loss of the activity; it was found that adenylate cyclase is quite labile and hence it could not yet been purified . The method used to determine adenylate cyclase activity and cyclic AMP is described.

Adv Exp Med Biol, 1980, 132, 509 - 17
Isolation of a lipocyte-rich fraction from rat liver nonparenchymal cells; Otto DA et al.; A modified pronase digestion procedure is described for isolating nonparenchymal liver cells from vitamin A treated rats, which yielded a 15-23% population of lipocytes in the total cell suspension . The criteria for defining a lipocyte was the appearance of vitamin A containing cells as determined by fluorescent microscopy . Measurement of alcohol dehydrogenase and retinol dehydrogenase activities indicated that these enzyme activities were not present in the isolated nonparenchymal cells . A lipocyte-rich fraction of nonparenchymal cells was obtained by centrifugation of purified nonparenchymal cells in a linear Metrizamide gradient . Vitamin A fluorescence and chemical assay of vitamin A in the cell fractions indicated a four-fold enrichment of lipocytes in the cell fraction with d = 1.043 g/ml . Fractions high in vitamin A also had numerous cells with fat droplets as shown by transmission electron microscopy.

J Clin Lab Immunol, 1980 Jan, 3(1), 51 - 61
Lymphocyte subpopulations in the thymus of SJL/J mice: age-related alterations and the effect of spontaneous reticulum cell sarcoma development; Dumont F; The cellular composition of the thymus was investigated as a function of age in the immunologically aberrant SJL/J mouse strain . Lymphocyte subpopulations were identified by combined analysis of cell electrophoretic mobility (EPM) and cell electronic volume and by assessment of surface receptor for Peanut-agglutinin (PNA) and of surface immunoglobulin (slg) determinants . In the thymus from young adult animals two major types of thymocytes could thus be recognized . The first one (th1, 2, 3) representing about 75% of the thymocyte population was endowed with a low-EPM and exhibited PNA-receptors . The other one (th4) possessed a high-EPM and lacked PNA-receptors . During ageing of mice selected for the absence of macroscopically detectable Reticulum Cell Sarcoma (RCS) lesions, the frequency of th1, 2, 3 cells diminished whereas that of th4 cells increased (up to 75% at the age of 16 months) . This latter augmentation reflected a true expansion of the th4 cell subpopulation and acounted for the maintenance of thymus cellularity to a relatively high level throughout life . In accordance with the probable immunocompetence of th4 cells, thymus cell suspensions from old RCS-free SJL/J mice were found to exhibit high proliferative responses to T-cell mitogens . On the other hand, from the age of 8 months onwards, a new physical type of lymphocytes (th5) could be detected in increasing proportions . These cells were characterized by a lower EPM than typical th1, 2, 3 thymocytes and by a modal volume around 150 micrometer3 . They were further demonstrated to be PNA- but slg+ and are thus likely to represent B cells . Such alterations were not encountered in BALB/c and DBA/2 mice in which both th1, 2, 3 and th4 thymocyte subpopulations regressed at approximately the same rate with age . Moreover, in the thymus of RCS-bearing SJL/J mice, the hyperplasia of the th4 cell pool and the occurrence of th5 cells appeared less important than in RCS-free mice.

J Invest Dermatol, 1980 Jan, 74(1), 54 - 8
The epidermal cell which selectively adheres to a collagen substrate is the basal cell; Stanley JR et al.; In order to determine whether a specific subpopulation of epidermal cells selectively attaches to collagen substrates in vitro, epidermal cell suspensions, obtained by trypsinization of guinea pig skin, were incubated on type I or type IV collagen-coated glass cover slips . It was noted, morphologically and by electronic volume measurements, that small round cells, as opposed to the larger angulated flat cells, adhered to the collagen substrates . To further characterize the attached cells, the percentage of basal cells was determined in the attached cell population and in the initial epidermal cell suspension . Basal cells were identified by indirect immunofluorescence in 2 ways: (1) by the presence of pemphigoid antigen and (2) by the absence of upper cytoplasmic antigen, which is present in all keratinocytes except the basal cells . Whereas in the initial guinea pig epidermal cell suspensions about 50% of the cells were basal cells using either of these 2 criteria, 86-97% of the cells which adhered to the collagen substrates were basal cells . Human basal cells, as defined by pemphigoid antigen, also selectively adhered to the collagen substrates.

Scand J Immunol, 1980, 11(4), 401 - 8
Studies on human epidermal Langerhans cells . I . Allo-activating and antigen-presenting capacity; Braathen LR et al.; Human epidermis was separated from dermis by means of a suction blister device and dissociated with trypsin . The epidermal cell suspensions obtained contained 3--5% Langerhans cells as judged by immunofluorescence staining ot the cells with a rabbit anti-DR antiserum . The epidermal cells were co-cultured with purified allogeneic T cells and with autologous T cells with or without PPD of tuberculin . A strong T-cell response to allogeneic epidermal cells was obtained, as was a strong T-cell response to PPD, provided autologous epidermal cells were also present . Pre-treatment of the epidermal cells with anti-DR antiserum plus complement abolished both these responses . These data indicate that epidermal cells are able to substitute for macrophages both in the allo-activating and in the antigen-presenting function . Since the responsible cells were DR-positive, it is highly probable that the cells responsible for these functions are the Langerhans cells.

Ann N Y Acad Sci, 1980, 341, 57 - 66
Coupling of ion flows in cell suspension systems; Geck P et al.; A valid test for cotransport between solutes is a demonstration that the degree of coupling between all coupled solute flows concerned, q defined in terms of Irreversible Thermodynamics, is sufficiently close to unity . The usual method to determine q kinetically by pulses and responses of flows can not simply be applied to rheogenic ion flows, as electrical potential difference changes due to the pulses can hardly be avoided . If, however, the ion flows are all electrically silent, changes in electrical potential difference (PD.) should not interfere with the determination of q . This holds for the furosemide-sensitive fluxes of Na+, K+, and Cl- in Ehrlich cells, each of which could be shown to be unaffected by a change in electrical PD and vice versa . Hence the q values could be determined for any pair of the three ion flows concerned and none differed significantly from unity . These results appear to indicate a furosemide-sensitive, electrically silent ternary symport mechanism for Na+, K+, Cl- with the stoichiometry 1:1:2, which is active but does not utilize ATP . It is assumed to function as a very efficient regulator of cellular volume and may be identical with other previously described binary symport systems.

Dev Biol Stand, 1980, 46, 67 - 74
A novel rapid and continuous method for the resolution of cell dispersal activities in crude trypsin preparations; Dickerson CH et al.; High speed continuous electrophoretic fractionation of crude commercial trypsin preparations has resulted in the resolution of the cell monolayer dispersal activity into three fractions, two of which were considered useful in the production of fully dispersed single cell suspensions . This separation could be achieved at an input rate for crude enzyme of 500 mg per minute.

Acta Biol Med Ger, 1980, 39(11-12), 1165 - 75
{In vitro cultivation and behavior of aortic endothelium cells in a low serum culture medium}; Halle W et al.; Endothelial cells isolated from calf aorta were used in the subculture No . 4 to 10 for experiments to establish standardized and well reproducible conditions of cultivation . The cells can be cultivated in the commercial medium Eagle-MEM with following supplements: 0.1 g L-glutamine, 5.0 g peptone, 0.5 g serum albumin, and 10 ml (= 1%) bovine serum per 1000 ml medium (MEMPAS) . With the aid of immunofluorescence technique the cell type specific marker Factor VIII antigen was shown to be localized especially in the perinuclear region of the cells . The cells were characterized with regard to their growth behaviour . Both, the MEMPAS and the Eagle-MEM with 10 per cent serum increases the cell number in the first 4 days of the exponential growth to the same values . The use of MEMPAS in connection with a strict cultivation regime from the deep frozen cell suspension to culture in scintillation vials guaranteed well reproducible conditions of cultivation . In 14 non-selected experiments distributed over a longer period of time it was found that with regard to the values of the cell number on the respective day the cultures can be divided into two groups, which differ with statistical significance . In further experiments it was possible to confirm this result . Medium, conditioned by endothelial cells (K-MEMPAS) increases the cell number and the growth rate . From these results it was concluded that endothelial cells of vessels are able to produce growth factors with self-stimulating effects . At this time the endothelial cell line is stored in deep frozen state up to the 25th subculture . The endothelial cells cultivated in the described standardized conditions are useful for screening of cell type specific factors with angiogenic activity.

Arzneimittelforschung, 1980, 30(7), 1119 - 23
{Nucleic acid and protein synthesis of splenic lymphocytes of the rat under the influence of mucopolysaccharide-polysulfuric acid-esters (author's transl)}; Tempel K; The influence of three mucopolysaccharide-polysulfuric acid-esters (MPS) of different molecular weight on DNAase II-activity as well as on nucleic acid and protein synthesis of lymphocytes of rat spleen has been investigated in vitro . The results are summarized as follows: 1 . DNAase II-activity (bovine spleen) was inhibited by MPS in a competitive manner . 2 . At concentrations of greater than or equal to 10 microgram/ml MPS decreased the incorporation of 3H-thymidine and 14C-uridine into the nucleic acids of the cell suspension . 3 . Incorporation of 3H-amino-acids into the lymphocytes protein was enhanced when MPS were added at concentrations of > 1 and > 10 microgram/ml, resp . At lower concentrations of the polyanions, a slight inhibition of protein synthesis was shown . 4 . In the presence of MPS, incorporation of the radioactively labelled presursors into the acid-soluble fraction of the cells was enhanced . 5 . The MPS-effects described increased with the molecular weight of the polyanions . It is suggested that polyanions like MPS may interfere rather non-specifically with cell membranes and with nucleic acid-polymerases.

J Natl Cancer Inst, 1980 Jan, 64(1), 89 - 96
In vivo T-lymphocyte response against spontaneous reticulum cell neoplasms in SJL/J mice; Weinstein Y et al.; The properties of lymphocytes associated with reticulum cell neoplasms (RCN) (type B) occurring spontaneously in SJL/J mice were examined . The activity of 20 alpha-hydroxysteroid dehydrogenase (20 alpha-SDH) was used as a marker for activated T-cells . High levels of this enzyme were found in cell suspensions of tumors taken from 6- to 7-month-old mice . Treatment of the cells derived from tumorous organs with anti-theta serum and complement resulted in a loss of the 20 alpha-SDH activity; this indicated that T-lymphocytes populate the RCN . The activated T-cells in the neoplastic tissue were larger than small lymphocytes . In the more advanced stage of tumor growth seen in 1-year-old mice, the percentage of malignant reticulum cells was low and the neoplastic tissue showed low levels of 20 alpha-SDH activity . Tumor cells irradiated in vitro triggered syngeneic lymphocytes to proliferate in tumor-lymphocyte mixed cultures . The T-cell proliferative response measured by {3H}thymidine incorporation was accompanied by a marked increase in 20 alpha-SDH activity . The spleen cells taken from mice bearing old tumors that showed marked fibrosis did not respond to T- and B-cell mitogens . Histologically, the structure of the spleen was preserved, with few or no tumor cells . Spleen cells from age-matched healthy mice responded to mitogens.

Horm Res, 1980, 13(4-5), 259 - 79
In vitro secretion of ACTH, beta-endorphin and beta-lipotropin in Cushing's disease and Nelson's syndrome; Ludecke DK et al.; Tissue from histologically confirmed ACTH cell adenomas in Cushing's disease (CD) and Nelson's syndrome (NS) was gained by transsphenoidal surgery . Combined enzymatic and mechanic agitation of tumor tissue yielded a cell suspension . Aliquots of the cell suspension were transferred to superfusion chambers immediately after isolation and investigated for ACTH and beta-endorphin production . Feedback action of cortisol (CO) and dexamethasone on basal hormone production and on lysine vasopressin (LVP) induced ACTH secretion were studied . Adenomatous tissue and anterior lobe tissue from the same patient in CD could be investigated simultaneously in 4 cases . The paraadenomatous tissue showed depression of basal and LVP-induced ACTH secretion . In all adenomatous tissues investigated there was missing or reduced suppression of basal ACTH secretion by physiological levels of CO . CO not only failed to suppress LVP-induced ACTH secretion but also seemed to enhance LVP stimulation in some experiments . This study confirms former results, that a missing or inversed feedback action or glucocorticoids in adenoma cells is a mechanism involved in the pathological ACTH secretion in CD and NS . Bioassayable and immunoreactive ACTH from media of superfusion and short-term static incubation were compared with beta-endorphin and beta-LPH in an assay detecting these two peptides with equimolar sensitivity . Secretory patterns were basically parallel but great differences showed in quantities of hormones secreted . In addition, Sephadex G-50 gel chromatography was performed to separate beta-endorphin from beta-LPH and to calculate the ratios . These profiles show great variations between different adenomas.

Acta Radiol Oncol, 1980, 19(5), 361 - 8
Effects of acute gamma-irradiation on spermatogenesis as revealed by flow cytometry; Hacker U et al.; Mice irradiated with doses ranging from 0.1 to 15 Gy using a 60Co-source and controls were killed at intervals varying from 2 to 35 days after irradiation . The DNA content of the testicular cells in single cell suspensions was measured with the pulse cytophotometer to determine the frequencies of the different stages in the spermatogenesis . The relative amount of S-phase and 4c-cells was reduced initially but increased subsequently to hypernormal values . A decrease of 2c-cells indicated a higher cell-kill of diploid spermatogonia . Gamma ray-induced spermatids with abnormal DNA-values (diploid sperm) were identified . The results suggest that the spermatogenesis can be analysed with flow cytometry and used as a biologic dosimeter even for small doses of ionizing radiation.

Physiol Bohemoslov, 1980, 29(2), 107 - 16
In vitro K+-effect on ATP and phosphocreatine levels and on Na+ K+-atpase activity of mouse brain cells; Kovaru H et al.; Cell suspensions were prepared form mouse brain cortices . Cells were incubated in a medium also containing 10 mmol.l-1 glucose and either 5 mmol l-1 K+ or 50 mmol.l-1 K+ concentration . In order to standardize individual experiments, the biuret reaction was modified for rapid determination of the protein in cell suspensions . The cellular reserves of energy-rich phosphates were determined in the course of 60 min of cell incubation with 5 mmol.l-1 K+ and following 30 min incubation of cells with 50 mmol.l-1 K+ . The level of ATP was significantly elevated after 10-60 min of incubation with low K+, from 0.58 to 0.78 micromoles per 100 mg protein; the creatine phosphate content during the same interval was in the range 1.27-1.44 micromoles per 100 mg protein . A significant decrease of energy reserves in cells was observed if the extracellular concentration of K+ was increased . After 10 and 30 min of incubation, a decrease by 36.2% and 38.5% for creatine phosphate and 34.6% and 44.9% for ATP was found, respectively . Na+ K+-ATPase activity of cells incubated for 60 min with 5 mmol.l-1 K+ was expressed as 4.99 micromoles of liberated Pi per 100 mg protein.1 h . Enzyme activity was stimulated with 50 mmol.l-1 K+ by 24.3% and 25.7% after 10 and 30 min of cell incubation respectively . Stimulation of Na+ K+-ATPase activity of brain cortex cells was directly dependent on the actual presence of stimulating 50 mmol.l-1 K+ concentration.

Prog Clin Biol Res, 1980, 48, 277 - 90
Further experience in testing the sensitivity of human ovarian carcinoma cells to interferon in an in vitro semisolid agar culture system: comparison of solid and ascitic forms of the tumor; Epstein LB et al.; We studied the in vitro growth characteristics of 10 solid-tumor samples of patients with ovarian carcinoma using a semisolid agar culture technique . Tumor cell colonies were observed in 8 of 10 samples, but sufficient number of tumor colonies to evaluate the effects of interferon and other antitumor agents were obtained in only four samples . As compared with cell suspensions prepared from ascitic fluid samples, solid-tumor samples had markedly lower viability, 39% vs 89%, and had more tumor cells, 81% vs 28% . Also, whereas the maximum increase in tumor-colony number occurred during the first week of growth in both solid- and ascitic-fluid-derived samples grown concurrently from the same donors, increase in tumor colony number was sustained for longer periods in ascitic-fluid-derived cultures . The ascitic-fluid-derived tumor colonies were more sensitive to the antiproliferative effects of interferon than colonies derived from solid-tumors . At a concentration of 300 units/ml incorporated into the agar for the duration of the culture, three of four ascitic fluid samples showed a reduction in tumor colony number by greater than or equal to 25%, whereas none of the solid-tumor samples were affected by the interferon to that degree . In contrast, solid-tumor samples showed greater response to cis platinum and Adriamycin than did ascitic-fluid-derived cultures . Such studies and observations are critical in designing clinical trials for the use of interferon in the treatment of malignancy and the judicious selection of patients and route of administration most likely to provide optimal results, especially in view of present critical shortages in availability of interferon.

Acta Derm Venereol, 1980, 60(5), 381 - 7
Studies on human epidermal Langerhans' cells: II . Activation of human T lymphocytes to herpes simplex virus; Braathen LR et al.; Epidermis from patients suffering from recurrent herpes labialis was separated from dermis by means of a suction blister device and dissociated with trypsin . The epidermal cell suspensions obtained were 80--95% viable and contained 3--5% Langerhans' cells, as judged by immunofluorescence staining of the cells with a rabbit anti-DR antiserum . T lymphocytes from the same patients were co-cultured with herpes simplex virus antigen (HSV-Ag) or live virus (HSV), with or without epidermal cells or macrophages . A strong proliferative T cell response to HSV-Ag and HSV was obtained, provided that the cultures also contained epidermal cells or macrophages . Pretreatment of the epidermal cells with a rabbit anti-DR antiserum plus complement abolished the responses, while pretreatment with normal rabbit serum plus complement did not . These data therefore indicate that HLA--DR positive Langerhans' cells are able to present herpes simplex virus in an immunogenic way to T lymphocytes.

Med Microbiol Immunol (Berl), 1980, 168(2), 129 - 37
Detection and spontaneous alteration of lymphocyte antigens on slide smears; Sassen A et al.; Smears of cell suspensions from murine lymphoid organs were prepared on slides, air dried, and processed for detection of immunoglobulin (Ig) and theta (Thy-1) antigens by the unlabeled antibody peroxidase-antiperoxidase (PAP) technique . Satisfactory results were obtained for both antigens on recently made smears . However, slides kept at room temperature showed a progressive decrease in staining of the two antigens with time . Various fixatives and preservation procedures were tested to prevent this alteration . Good conservation of smears was obtained when slides were kept at -18 degrees C and/or air isolated before or after fixation with alcohols . A similar degradation of Ig and/or Thy-1 antigens occurred also in histological tissue sections or in serum spots dried on slides . The major cause for this degradation is thought to be contact with air, residual enzymatic hydrolysis playing a less important role.

Int Arch Allergy Appl Immunol, 1980, 63(2), 153 - 8
Suppression of experimental allergic encephalomyelitis with thoracic duct lymphocytes; Frost H et al.; Thoracic duct lymphocytes (TDL) from Lewis rats immunized 9-10 days previously with basic protein in complete Freund's adjuvant (BP-CFA) failed to induce experimental allergic encephalomyelitis (EAE) in syngeneic recipients . This contrasts with the successful transfer of EAE by lymph node cell suspensions from donors immunized 9 days previously with BP-CFA . Only minor EAE was induced passively by TDL from rats immunized 11-12 days before with BP-CFA . TDL collected 9-20 days after BP-CFA immunization, however, were successful in transferring specific suppression of EAE tested by the lack of disease in the recipients immunized actively with BP-CFA 1 week after the TDL transfer . The data indicate that the thoracic duct contains specific suppressor cells shortly before, during and after the development of clinical EAE.

Folia Haematol Int Mag Klin Morphol Blutforsch, 1980, 107(1), 104 - 24
{Erythrocyte concentrates, low in buffy coat: production, preservation and evaluation of its quality.}; Strauss D et al.; Buffy coat-poor packed red cells were prepared from fresh ACD-, ACD-AG- and EDTA-blood, than resuspended with a preservation solution, containing glucose, adenine, guanosine, sucrose, citric acid and sodium citrate and stored at 4 degrees C for 6 weeks . The survival rate of resuspended red cells from ACD-AG-blood amounted to 77% after 6 weeks of storage . The ATP content of resuspended red cells was approximately 25% lower than in ACD-AG whole blood during storage caused probably by increased ATP consuming reactions at the red cell membrane . The P2G-content of resuspended red cells from ACD- and ACD-AG-blood decreased above 50% of the normal level during the first week, as fast as in ACD- and ACD-AG whole blood . The P2G-breakdown in red cells from EDTA-blood was delayed for a week due to the higher pH as in CPD blood . Additions of xylitol, inorganic phosphate, and bicarbonate in 6, 5 and 20 mM final concentrations in the red cell suspensions and an increased pH at the same time delayed the breakdown of ATP and P2G . Packed red cells can be administered fast enough at hematocrits to 0.60 that will be achieved by adding 50 to 100 ml preservation solution . Leukocytes and thrombocytes were reduceds to 70 to 80% . With increasing rate of reduction a higher loss of red cells occured . Buffy coat-poor red cell concentrate contains only few microaggregates . It diminishes the risc of febrile transfusion reactions and delays the appearance of alloimmunisation . The circulatory overload of patients is less frequent than after transfusions of red cell resuspensions containing a large resuspension volume.

Int Arch Allergy Appl Immunol, 1980, 62(2), 205 - 12
Histamine-containing cells from bronchial lavage of macaque monkeys . Time course and inhibition of anaphylactic histamine release; Butchers PR et al.; Bronchial lavage of rhesus and cynomolgus monkeys provided leucocyte suspensions with viable histamine-containing cells (HCC) as 1--8% of the white cell population . These HCC released histamine or challenge with antiserum to human IgE . HCC from 2 monkeys with pulmonary and cutaneous hypersensitivity to Ascaris antigen (AA) released histamine on challenge with AA . The extent of histamine release was related to the concentration of antigen and antiserum, and histamine release was complete within 10 min of challenge . (+/-)Salbutamol and (-)isoprenaline were potent inhibitors of anaphylactic histamine release from HCC, but disodium cromoglycate and AH 9679 were relatively poor inhibitors . The HCC system combines the reproducibility of a cell suspension with a response to drugs similar to that of human lung fragments.

Acta Biol, 1980, 31(1-3), 249 - 55
Rate of thymidine incorporation and incidence of parenchymal cell division in adult rat hypophyseal cell cultures . Effect of thyroliberin and somatostatin; Rappay G et al.; Cell suspensions derived from adult rat anterior pituitary glands were cultured for up to eight days . Prolactin immunoreactivity and/or tritiated thymidine incorporation into DNA of cell nuclei were demonstrated in cells with and without thyroliberin (TRH) and somatostatin (SRIF) treatment . It has been established that (a) TRH, which is effective in releasing both thyrotropin and prolactin, may stimulate cell proliferation in other than its target cells; that (b) SRIF has no effect on lactotropic cell proliferation and augments thymidine incorporation into DNA of unidentified cells; that (c) immunoreactive lactotropic cells with tritium-labelled nuclei are present in each culture, independent of hypothalamic hormone treatments.

Virchows Arch B Cell Pathol Incl Mol Pathol, 1980, 33(2), 127 - 38
A T-dependent plasma cell response: part of a graft-versus-host and host-versus-graft reaction in the rabbit spleen; Veldman JE et al.; B-cell reactivity, as expressed in a plasma cell reaction may be part of a graft-versus-host or host-versus-graft reaction . Cell transfer experiments were able to prove this . Histological evidence is presented for the occurrence of the so-called "allogeneic effect" during a graft-versus-host or host-versus-graft reaction in the rabbit spleen . Cell suspensions containing both T- and B-cells give rise to a cellular and a humoral immunity reaction component upon transfer to histoincompatible recipients . This can also occur during a graft-versus-host reaction . This B-cell response is T-cell dependent.

Virchows Arch B Cell Pathol Incl Mol Pathol, 1980, 33(2), 107 - 16
Diagnostic morphometry of isolated lymph node cells from patients with mycosis fungoides and Sézary's syndrome; van der Loo EM et al.; Mycosis fungoides (MF) and Sezary's syndrome are cutaneous T cell lymphomas, characterized by the presence of lymphoid cells with deeply indented nuclei (CMC) in the infiltrate . In order to find objective criteria for the diagnosis of early MF involvement of lymph nodes from patients with MF, we performed morphometric analysis of lymphoid cells in lymph node cell suspensions measuring the degree of nuclear indentation as expressed by the nuclear contour index (NCI) . Statistical discriminant analysis was used to analyze the differences in the NCI histograms between lymph nodes without and with MF involvement and to select the most discriminating parameters for diagnostic classification . Using a training set of 6 lymph nodes from patients with unrelated diseases and 8 lymph nodes from patients involved by cutaneous T cell lymphomas, the mean and standard deviation of the NCI histograms were selected as the most discriminating parameters . All lymph nodes from the training set were assigned to the correct diagnostic classification group with a probability over 90% . The predictive value of the morphometric classification was tested on a set of 12 enlarged lymph nodes from patients with MF . The histological diagnosis was used as a reference . In 10 cases the morphometric classification was identical to the histological classification, whereas in two cases (1 classified as positive, 1 as negative) a disagreement was found . It is concluded that morphometry of lymphoid cells can contribute substantially to the diagnosis of early MF involvement in lymph nodes.

Nature, 1979 Dec 13, 282(5740), 738 - 9
Shear-induced concanavalin A agglutination of human erythrocytes; Greig RG et al.; The mechanism by which cell suspensions are agglutinated by plant lectins remains obscure . The agglutination of a particular cell line in the presence of a specific plant lectin probably depends on several factors including the number and valence of lectin molecules bound to the cell surface, the mobility of receptor molecules in the membrane, the surface morphology and charge and the metabolic state of the cell1-6 . The assay system used to assess cell agglutination also seems to be important, since many laboratories studying the same agglutination reaction have reported dissimilar or contradictory results . To provide further information on the molecular mechanism of agglutination we have begun a systematic study on the aggregation of human red cells by the lectin concanavalin A (Con A) . By using an adaptation of our previously described aggregation assay which provides a continuous measure of both the rate and degree of intercellular adhesion in the presence of controlled shear forces, we have found that the agglutination of erythrocytes by Con A can be resolved into three stages, two of which are observed only if the system is exposed to shear.

Eur J Immunol, 1979 Dec, 9(12), 997 - 1003
Surface Ig on rabbit lymphocytes . Rabbit B and T cells are distinct populations; Bast BJ et al.; Rabbit peripheral blood lymphocytes (PBL) were analyzed by immunofluorescence using anti-T cell conjugates and anti-Fab, anti-a1 allotype, anti-IgM and anti-IgA conjugates . In addition, T cells were demonstrated by rosetting with papain-treated homologous erythrocytes . Control experiments, using acid treatment and incubation at 37 degrees C for 18 h after or without pronase treatment, revealed the endogenous origin of all surface determinants tested . A good correlation was found between results obtained with the two anti-T cell conjugates used and the T rosette test on PBL and on lymphoid cells isolated from various organs . In lymphocytes isolated from peripheral blood and from various lymphoid organs, the percentages of T and B cells were respectively 45 and 38 for PBL, 10 and 46 for bone marrow, 27 and 31 for appendix, 40 and 45 for spleen, 42 and 46 for Peyer's patches, 96 and 0.3 for thymus and 70 and 16 for peripheral lymph nodes . The percentage of "null" cells in lymphocyte populations derived from bone marrow and appendix is rather high . The final percentages of T and B cells in rabbit PBL depend to a significant extent on the method of isolation, especially isolation by Ficoll-Hypaque centrifugation results in a depletion of T cells . Moreover, a rather impure lymphoid cell suspension is obtained . In double incubation experiments, T cells (as defined by T cell antigen(s) or rosette formation) and B cells (Fab-bearing cells) were entirely different subpopulations . Allotypes of the a locus could not be detected on the surface of T cells . The results are discussed with respect to genetic coding of antigen receptors on B and T cells.

J Endocrinol, 1979 Dec, 83(3), 303 - 10
Varying response to luteinizing hormone of two luteal cell types isolated from bovine corpus luteum; Ursely J et al.; Luteal cell suspensions obtained by enzymatic digestion of pregnant cow corpus luteum were found to be heterogenous and mainly made up of two types of cells of different sizes . The large cells (37 micrometers, average diameter) could be separated from the small ones (18 micrometers, average diameter) by sedimentation at unit gravity in a gradient of Ficoll-bovine serum albumin . A comparative in-vitro study of the synthesis of progesterone by the two types of cells indicated striking differences between them . The average content and the synthesis of progesterone in the absence and presence of a saturating dose of bovine LH after incubation for 2 h were 0.07, 0.12 and 6.9 pg/cell for the small cells and 0.65, 2 and 10 pg/cell for the large ones . Moreover, the sensitivity to low concentrations of LH was 100 to 1000 times higher for the small cells than for the large ones . Oestradiol-17 beta at concentrations ranging from 5 X 10(-10) to 5 X 10(-4) mol/l exerted a dose-dependent inhibition on the stimulation of LH in both cell types . These results suggest a possible involvement of both cell types in the synthesis of progesterone in vivo with a greater contribution by the small cells to stimulation induced by LH . Moreover, it appears that small cell suspensions could be a useful model system for in-vitro studies of the control of the synthesis of progesterone in cow corpus luteum.

In Vitro, 1979 Dec, 15(12), 949 - 56
Tapping culture--an improved method for cell suspension culture; Katsuta H et al.; A new culture vessel was designed for cell suspension culture . A silicone-covered magnet bar fixed by one end to the side wall of the bottle was held horizontally a short distance from the bottom . A standard type magnetic stirrer was used . In contrast to the conventional horizontal movement of "stirring" in cultures the bar moves vertically with a "tapping" motion . This improvement resulted in less cell injury, higher rate of cell proliferation and formation of fewer bubbles than in the conventional type . Nine cell types were simultaneously cultivated in tapping, stirring and stationary culture . All cell types proliferated more luxuriously in tapping cultures then in stirring cultures . Serial cultivation of cells in tapping cultures was also successful.

J Cell Sci, 1979 Dec, 40, 271 - 9
The effects of EGTA and trypsin on the serum requirements for cell attachment to collagens; Schor SL; Cells growing on plastic or glass surfaces in vitro may be brought into suspension by proteases (e.g . trypsin) or chelating agents (e.g . EGTA) . Trypsin and EGTA remove different quantities and types of molecules from cell surfaces . Previous studies have revealed that when confluent cultures of either BHK or PyBHK cells are brought into suspension by exposure to trypsin, foetal calf serum (or fibronectin) is required for cell attachment to films of denature type I collagen, but not to 3-dimensional gels of native collagen fibres . In this communication the serum requirements for the attachment of BHK and PyBHK cells to collagen substrata have been examined as a function of (a) the method used to prepare the cell suspension (EGTA or trypsin), and (b) cell density . Data are presented consistent with the view that cell surface-associated fibronectin is able to mediate cell attachment directly to films of denatured collagen.

Biull Eksp Biol Med, 1979 Dec, 88(12), 693 - 5
{Suppression of delayed hypersensitivity in mice receiving a massive dose of xenogeneic erythrocytes}; Chernousov AD et al.; The injection of 6x109 sheep red blood cells to mice suppresses delayed-type hypersensitivity (DTH) in situ and activates spleen cells which prevent sensitization of recipients . Preliminary thymectomy of donors and the treatment of cell suspensions with anti-T-globulin abolish suppression of DTH . Pretreatment of mice with low doses of cyclophosphamide (CY) enhances antibody formation and DTH . Higher doses of CY increase the DTH reaction but inhibit antibody formation . The data obtained allow to conclude that suppression of DTH is due to the activity of short-living, intensively proliferating cells of thymic origin and possibly to B cells.

Appl Environ Microbiol, 1979 Dec, 38(6), 1147 - 52
Sublethal stress in Escherichia coli: a function of salinity; Anderson IC et al.; Sublethal stress in Escherichia coli was detected in various test media after exposure (in vitro) to seawater of various salinites . Stress was measured with an electrochemical detection technique and a beta-galactosidase assay . Test media included EC medium, medium A-1, and tryptic soy broth modified to contain lactose for beta-galactosidase assay experiments . Stress was defined as the difference between a predicted electrochemical response time calculated for unstarved cells from a standard curve and the observed electrochemical response time for cells starved in seawater . The higher the salinity, the greater the stress for all test media examined . Stress was most pronounced in EC and was attributed primarily to initial die-off of starved cells exposed to the test medium at the elevated temperature of 44.5 degrees C . Lag time and growth rates in test media were not significantly affected by salinity . beta-Galactosidase specific activity, assayed in starved cells after transfer to an induction medium at 44.5 degrees C for 150 min, was inversely related to the salinity of the starved cell suspension . The consequences of these observations with respect to coliform enumeration methods are discussed.

Arch Int Physiol Biochim, 1979 Dec, 87(5), 925 - 34
Cytochalasin E-induced oxidative metabolism in polymorphonuclear leukocytes; Heyneman RA; The extent of the cyanide-resistent oxidative burst of polymorpho-nuclear leukocytes after stimulation with cytochalasin E was shown to depend markedly on the osmolarity of the cell-suspension medium . With granulocyte concentrations up to 2 X 10(6) cells/ml, optimal oxygen consumption and releases of H2O2 and superoxide anions were reached at 180 mOsmol and 2 X 10(-5) M cytochalasin E . After removal of unbound activator, the cellular oxidative activity remained unaltered and continued to depend on the used osmotic conditions . It is proposed that binding of cytochalasin to the plasma membrane induces an irreversible activation of the oxidative system, whereas the resulting metabolic activity depends on conformational changes in the plasma membrane.

J Membr Biol, 1979 Nov 30, 50(3-4), 311 - 29
Manganese as a calcium probe: electron paramagnetic resonance and nuclear magnetic resonance spectroscopy of intact cells; Getz D et al.; When Lettree cells are exposed to Mn2+, the cation becomes associated with cells in two ways: in a relatively loose and mobile manner that gives a six-line EPR spectrum designated Mnb*, and in an immobile, relatively tight manner that gives no detectable EPR specrtum, designated Mnb . Mnb* is probably on the surface of cells; most Mnb is probably inside cells . NMR measurements of Lettree cell suspensions show two water proton relaxation rates and confirm the existence of cell-associated Mn . Human erythrocytes, on the other hand, bind no Mn2+ under these conditions, as judged by EPR and NMR measurements . Virally-treated Lettree cells show an increase in Mnb (but not in Mnb*) . They also show a third water proton relaxation rate.

Prikl Biokhim Mikrobiol, 1979 Nov-Dec, 15(6), 883 - 8
{Determination of cytochromes in chloroplasts of Chlamydomonas reinhardii mutants}; Roshchina VV et al.; A method for qualitative determination of cytochromes of the wild-type and mutant strains of Chalmydomonas reinhardii was developed . The effect of different techniques of cell disruption (ultrasound, Triton X-100, acetone, etc) on detection of cytochrome maxima in the oxidized minus reduced difference spectra was studied on a comparative basis . The development of the stable difference spectrum of the disrupted cell suspension was shown to be a function of incubation time in the presence of an oxidizing or a reducing agent . Cytochromes of the wild-type and 10 nonphotosynthesizing mutants were determined . Four mutants with lesions in cytochromes B559 and C553 were detected . Mutants with lesions in the reaction center of photosystem 2 were found to have a substantially reduced content of cytochrome B559, whereas those with normal photosystems--of cytochrome C553.

Microsc Acta, 1979 Nov, 82(3), 251 - 3
Dissociation of rat colonic mucosa into single epithelial cells and their microscopic visualization; Herp A et al.; Repeated incubation of rat colonic mucosa with phosphate-buffered mannitol yields morphologically intact single cell suspensions which are easily visualized microscopically with trypan blue . Cell dimensions are determined by means of a Nikon microcomparator.

J Clin Pathol, 1979 Nov, 32(11), 1180 - 3
A sensitive single reverse passive haemagglutination test for detecting both HBsAg and anti-HBs; Barbara JA et al.; A trial of a modified reverse passive haemagglutination test for HBsAg using a 0.1% cell suspension instead of the recommended 1% showed an approximately eight-fold increase in detection sensitivity . The test can be performed within 30 minutes and lends itself to mass screening techniques . Confirmation tests can be done using the 0.1% method . In addition, the same serological plates and cells used for HBsAg screening can then be used to screen for high-titre anti-HBs . This makes the overall screening for both HBsAg and high-titre anti-HBs donors cheap and convenient.

Eur J Biochem, 1979 Nov 1, 101(1), 225 - 33
Purification and properties of strictosidine synthase, the key enzyme in indole alkaloid formation; Treimer JF et al.; A new enzyme, strictosidine synthase, which catalyzes the synthesis of 3-alpha(S)-strictosidine from tryptamine and secologanin was isolated from the soluble protein extract of Catharanthus roseus cell suspension cultures and was purified approximately 50-fold by ammonium sulfate fractionation, column chromatography on DEAE-cellulose . Ultrogel AcA34 and isoelectric focusing . The apparent molecular weight of the enzyme was 34000 . The pH optimum was 6.8, apparent Km values for tryptamine and secologanin were 2.3 mM and 3.4 mM respectively for the enzyme to synthesize strictosidine . Strictosidine synthase shows high substrate specificity . No apparent cofactor requirement could be demonstrated . Of several enzyme inhibitors tested, only p-chloromercuribenzoate inhibited the enzyme . The enzyme was relatively stable and could be stored at -20 degrees C for periods of up to 1 year without appreciable loss of catalytic activity . The enzyme was demonstrated to occur in suspension cultures of 15 different species belonging to 9 different genera of the indole-alkaloid-producing subfamily Plumerioideae of the Apocynaceae family . This enzyme is responsible for the synthesis of strictosidine the key intermediate in the formation of the majority of monoterpenoid indole alkaloids occurring in the plant kingdom.

Blut, 1979 Nov, 39(5), 333 - 44
Red cell filtration by paper filters; Staubli M et al.; A method for the assessment of red cell filterability with paper filters is described . Two milliliters of a washed red cell suspension with a hematocrit of 50% was filtered through a filter paper cone in a glass funnel and the filtration half-time (FT1/2) was measured . The filter papers were calibrated by previous measurement of the filtration time for the suspending solution, the calibration time (CT) . A linear correlation between CT and FT1/2 was found for individual red cell suspensions (p less than 0.001) as well as for a normal population (p less than 0.001) . Consequently, the index FT1/2/CT should represent a more reproducible parameter than FT1/2 and experimentally this appears to be the case . In fact, elimination of erratic values in a normal population was realized . Furthermore, discrimination between normal and abnormal values was improved and the coefficient of variation of single measurements passed from 28.4 to 9.4% . The reproducibility and reliability of this extremely simple method are therefore decisively enhanced without complication of the procedure.

Int J Radiat Biol Relat Stud Phys Chem Med, 1979 Nov, 36(5), 435 - 51
Effect of salt solutions on the radiosensitivity of mammalian cells as a function of the state of adhesion and the water structure; Moggach PG et al.; The radiation isodose survival curve of attached Chinese hamster (V79) cells, subjected to a wide concentration range of salt or sucrose solutions, is characterized by two maxima separated by a minimum . Cells are radioprotected at the maxima (high and low hypertonic salt concentrations) while they are radiosensitized at the minimum (intermediate hypertonic salt concentrations) . Both cations and anions can alter the cellular radiosensitivity above and beyond the (osmotic) effect observed for cells treated with sucrose solutions . However, the basic curve shape, except in the case of sulphate salts, remains the same . When these experiments are repeated with single cells in suspension, the isodose survival curve is quite different in that high salt concentrations (greater than 0.9 M) do not protect cells in suspension unlike the case with attached cells . The curve shape is also altered in that the second maximum is absent with many salt solutions . If multicellular spheroids are used for these experiments, the data resemble those for single cell suspensions rather than for attached cells . The radiation survival data for cells in suspension in salt solutions correlate with water proton spin-lattice relaxation time (T1) and, in hypo- and iso-tonic solutions, with cell volume.

Anal Quant Cytol, 1979 Nov-Dec, 1(3), 228 - 32
The use of percent volume analysis in Coulter sizing of cells in gynecologic cytopathologic cell suspensions; Leary JF et al.; The Coulter Counter model TA II was evaluated as a gynecologic cytodiagnostic tool . The instrument produces particle size histograms as plots of percent volume versus particle volume in 16 channels with each channel corresponding to twice the volume of the next lower channel . Cell volume distributions were obtained using cell suspensions from patients with cervicitis, inflammation, dysplasia or carcinoma and were compared with those from normal subjects . Although this method is superior to other methods of volume distribution analysis, it does not satisfy the stringent requirements of a cervical cancer mass screening method.

Tsitologiia, 1979 Nov, 21(11), 1372 - 3
{Method of cell cultivation in microdishes}; Kovalev SP; A method is proposed of cell cultivation on the microscopic glass . Glass rings with inner diameter of 6 mm are fixed on prepared glasses . A simple of 0.2 ml cell suspension is poured into so-formed microcups . The cultivation is carried out in hermetic Petri dishes under conditions of the 5% CO2 atmospheric saturation at 37 degrees C.

Br J Cancer, 1979 Nov, 40(5), 689 - 700
Association of host immunoglobulins with solid tumours in vivo; James K et al.; Using a direct radioimmune antiglobulin technique and a competitive double-antibody radioimmune assay, we have demonstrated the presence of appreciable amounts of host immunoglobulins on the surface and in extracts of cell suspensions from freshly excised solid tumours . IgA appeared to have the greatest concentrations from freshly excised solid tumours . IgA appeared to have the greatest concentration, followed in turn by IgM congruent to IgG2a greater than IgG1 congruent to IgG2b greater than IgG3 . The amount of immunoglobulin appeared to be influenced by the tumour under investigation and its mode of maintenance . It could also be increased by the administration of C . parvum but was not significantly influenced by the T-cell status of the host.

Endocrinology, 1979 Nov, 105(5), 1183 - 90
Sulfhydryl reagent-induced insulin release and 45Ca++ fluxes in Syrian hamster insulinoma cells; Erlichman J et al.; Dispersed single cell suspensions of Syrian hamster insulinoma cells were used to study the effects of a variety of sulfhydryl-binding reagents on insulin release and 45Ca++ flux . Incubation of cells with several organic mercurials resulted in a rapid increase in 45Ca++ uptake as well as increased efflux in cells which had been prelabeled with 45Ca++ . Concomitant with increased calcium uptake was a 4- to 5-fold increase in insulin released into the medium . Incubation with alkylating reagents such as iodoacetamide and N-ethyl maleimide or dithiol reagents such as 5,5'-dithiobis (2-nitrobenzoic acid) failed to stimulate either 45Ca++ flux or insulin release . Elimination of medium calscium or preincubation of cells with N-ethyl maleimide resulted in approximately 50% inhibition of mercurial-induced insulin release from these cells . 8-(N,N2-diethylamino)Octyl-3,4,5-trimethoxybenzoate or alpha-isopropyl-alpha {(N-methyl-N-homoveratryl)-gamma-aminopropyl}3,4,5'-trimethoxyphenylacetonitrite hydrochloride, agents which block potassium (40 mM)-stimulated calcium flux and insulin release, failed to inhibit mercurial-induced calcium flux or insulin secretion . These results indicate that sulfhydryl-binding reagents, through their interaction with critical thiol groups, promote insulin release in these insulinoma cells by inducing changes in calcium fluxes . It is possible that these thiol groups regulate calcium metabolism and, thus, insulin release under physiological conditions.

J Cell Biol, 1979 Nov, 83(2 Pt 1), 271 - 83
Characterization of gastric mucosal membranes . X . Immunological studies of gastric (H+ + K+)-ATPase; Saccomani G et al.; Gastric mucosal homogenates from hog were fractionated by differential and density gradient centrifugation and free-flow electrophoresis . The two major membrane fractions (FI and FII) thus obtained are distinct both enzymically and in terms of transport reactivity . This heterogenicity extends to their antigenic activity . Purified antibodies which were raised against the K+-ATPase-containing H+ transport fraction FI were of two types: inhibitory and non-inhibitory . Inhibitory antibodies reduced the K+-ATPase activity by approximately 80% and the K+-p-nitro-phenylphosphatase activity by approximately 40% in a concentration-dependent manner, while the small Mg++-dependent component of the enzyme activity was unaffected . Antibodies inhibiting the K+-ATPase also inhibited H+ transport . These antibodies did not cross-react with the other major membrane fraction isolated by free-flow electrophoresis, FII, and gave a single band on rocket immunoelectrophoresis . Antibodies against this FII fraction also did not react with the K+-ATPase and were heterogeneous, giving at least four bands with rocket immunoelectrophoresis and inhibiting both the 5'-nucleotidase and Mg++-ATPase of this fraction . Immunofluorescent staining of tissue sections showed that the FI was derived from the parietal cell of gastric tissue and was localized to the supranuclear area of the cell . Staining of isolated rat gastric cell suspensions by FI antibodies confirmed the selectivity of the antibody and showed a polar, plasma membrane localization . FII antibodies also largely stained the parietal cells in tissue sections . In the 16 hog tissues tested, FI antibodies cross-reacted only with gastric fundus, thyroid and weakly with thymus . Immunoelectronmicroscopy showed that FI antibodies reacted strongly with the secretory membrane at the apical cell surface of the parietal cells and at the secretory canaliculi, weakly with the apical surface of the zymogen cell, and not with the basal-lateral surface of the cells . Thus, the protontranslocating ATPase is localized in the parietal cells and in the region postulated to be the site of acid secretion.

Cancer, 1979 Nov, 44(5), 1622 - 8
Studies of mixed lymphocyte reactions, surface B cell antigens, and intracytoplasmic immunoglobulins in "null cell" acute lymphocytic leukemia; Davey FR et al.; Lymphoblasts from "null cell" acute lymphocytic leukemia (ALL) were analyzed for the pattern of proliferation displayed in a mixed lymphocyte reaction (MLR), the presence of a B cell surface antigen, and for the presence of intracytoplasmic immunoglobulin (ICIg) . "Null cell" ALL was defined by cytologic and cytochemical criteria and by the absence of spontaneous rosette formation and surface membrane immunoglobulin in cell suspensions of the malignant lymphocytes . In eleven of fourteen patients the proliferative characteristics of lymphoblasts in the MLR were similar to those observed with normal B enriched lymphocytes . In eleven cases studied, anti-B cell serum reacted with a majority of the lymphoblasts . None of the ten cases examined displayed ICIg in the lymphoblasts . We conclude that the "null" lymphoblast from most cases of ALL is a B cell in an early stage of development.

Infect Immun, 1979 Nov, 26(2), 448 - 52
Ability of enriched immune T cells to confer resistance in hamsters to infection with Treponema pertenue; Chan JK et al.; This investigation presents the first direct evidence that T cells are involved in resistance to challenge with Treponema pertenue . Enriched T cells from immune hamsters were obtained by sequential filtration through glass and nylon-wool columns . This procedure removed the majority of functional antibody-producing and immunoglobulin-bearing cells . The fractionated cell suspensions were less responsive to stimulation by phytohemagglutinin, lipopolysaccharide, and dextran sulfate, but they were enriched with antithymocyte-sensitive cells and were more responsive to stimulation with concanavalin A . Hamsters receiving fractionated or unfractionated immune cells had no cutaneous lesions 21 days after infection and had significantly lower lymph node weights and fewer treponemes per node than hamsters that received fractionated or unfractionated normal cells . Resistance was transferred with immune cell suspension enriched in T cells despite an absence of anamnestic antibody response to specific treponemal antigens.

J Biochem (Tokyo), 1979 Nov, 86(5), 1291 - 300
Preparation and characterization of an active lysozyme derivative: Kyn 62-lysozyme; Yamasaki N et al.; A novel method for the preparation of Kyn 62-lysozyme, in which tryptophan 62 is replaced by kynurenine, is reported . Hen egg-white lysozyme was ozonized in aqueous solution to yield one N'-formylkynurenine residue and deformylated with hydrochloric acid in frozen solution at -10 degrees C . Crude Kyn 62-lysozyme was purified by affinity and Bio Rex 70 chromatography successively . Kyn 62-lysozyme retains affinity for chitin and is essentially an active enzyme with a slightly weakened but distinct catalytic activity . After this modification, the enzyme activity was changed differently depending on the kind of substrate . At the individual optimum pH's, lytic activity was largely retained (80% active), but the catalytic efficiency for hydrolyzing glycol chitin was relatively low (30% active) . Lysis of M . lysodeikticus cell suspensions was optimally catalyzed by Kyn 62-lysozyme at pH 6.2 and at 0.088 ionic strength . These values are lower by 1.3 pH unit and 0.04 ionic strength, respectively, than those of intact lysozyme . The optimum pH and ionic strength for the hydrolysis of neutral substrates were scarcely affected . These results suggest the significance of electrostatic interaction in the lysis of lysozyme . Relatively limited loss of activity induced by modification of the 62nd residue, which is thought to participate directly in the binding of the substrate at subsite C, is discussed on the basis of the similarity of side chain structure in tryptophan and kynurenine.

Int J Cancer, 1979 Oct 15, 24(4), 450 - 4
Contribution of macrophages to interactions between tumor cells and other tissues assessed in an in vitro system; Maslow DE et al.; The modification of the tissues surrounding solid tumors is usually attributed exclusively to interactions between the normal tissues and the cancer cells in the tumor, in spite of the fact that tumors contain many different types of non-cancer cells including macrophages . As an experimental model for some facets of the cellular interactions between tumor and normal tissues, we have assessed the individual contributions of macrophages and cancer cells to the differential inhibition of neural retina (NR) cell aggregation by co-culturing NR cells with small numbers of macrophages or cancer cells alone, as well as with both natural (ascites tumors) and artificial mixtures . Cells from human colonic adenocarcinoma inhibited NR aggregation to a greater extent than normal colon mucosa . Aggregation of NR cells was inhibited by macrophages from mice and rats, and to a greater extent by cancer cell suspensions of mouse Ehrlich and rat Walker 256 lines from spinner culture or in the ascites form . Combinations of macrophages and cancer cells indicated that their inhibitory effects were neither additive nor synergistic . Cell-free media from macrophages and cancer cell cultures were equally effective inhibitors of aggregation . The results suggest that the interaction between a malignant tumor and the surrounding normal tissue can be modified by cancer cells, tumor macrophages and their products.

Nature, 1979 Oct 11, 281(5731), 497 - 9
Evidence for a charge-shift electrochromic mechanism in a probe of membrane potential; Loew LM et al.; Extrinsic optical probes have become important tools for monitoring membrane potential, with probes now available for many tissue or cell suspension systems . In each case that has been studied in detail, it seems that the mechanism involves a shift in the equilibrium population of the probe from one chemical environment to another in response to the transmembrane potential; the environments perturb the probe's spectrum differently . As this indirect mechanism involves a redistribution of dye between chemical environments that are likely to vary if a given probe is transferred from one membrane to another, a potential probe that is effective and calibrated for all membrane systems has not been realised . We present here evidence for a direct response of a probe chromophore to the electric field across membrane systems . The results suggest it might be possible to develop a universal set of membrane probes.

J Membr Biol, 1979 Oct 5, 50(1), 23 - 41
HCO3-/Cl- exchange across the human erythrocyte membrane: effects of pH and temperature; Obaid AL et al.; Changes in extracellular pH (PH0) in red cell suspensions were monitored in a stopped-flow rapid reaction apparatus under conditions where dpH0/dt was determined by the rate of HCO3-/Cl- exchange across the membrane . Experiments were performed at 5 degrees C less than T less than 40 degrees C using either untreated cells or cells exposed to 0.11 mM SITS (4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid) . Although SITS exposure reduced the rate of exchange by 90%, both untreated and SITS-treated cells are similarly affected by changes in pH0 and temperature . The rate of HCO3-/Cl- exchange exhibits a minimum at about pH0 5 and a maximum at about pH0 7.4 at all temperatures . A transition temperature of 17 degrees C was observed in the Arrhenius relationship for all pH0 . The activation energies (Ea) in kcal/mol are 19.6 below and 11.7 above 17 degrees C for 5 less than pH0 less than 8 . These findings, similar to those reported for Cl- self-exchange, suggest that: (i) a change in the rate-limiting step for HCO3-/Cl- exchange occurs at 17 degrees C, possibly due to an altered interaction between the transport pathway and membrane lipids; (ii) the carrier system can be titrated by either H+ or SITS from the outside of the membrane, but the untitrated sites continue to transport normally; (iii) the pH0 dependence of the rate of exchange is consistent with the titratable carrier having its most alkaline pK in the range expected for amino groups; and (iv) below pH0 5, the nature of the exchange is markedly altered.

Br J Exp Pathol, 1979 Oct, 60(5), 499 - 506
Comparative studies of the metastatic potential of three transplantable rat mammary carcinomas of spontaneous origin; Willmott N et al.; The metastatic potential of 3 spontaneously arising mammary carcinomas (Sp4, Sp15 and Sp22) has been examined when transplanted in the form of a viable cell suspension into the tissue of origin . Primary tumours were excised at different times after implantation and it was found that the metastatic potential of the immunogenic tumour Sp4 was directly correlated with the size of the primary tumour when excised . By contrast, the incidence of metastases from the non-immunogenic tumours Sp15 and Sp22 was similar irrespective of the size of the primary tumour on excision . The pattern of metastasis also differed between the tumours, although here there was no relation to immunogenicity . Thus, resection en bloc of large primary Sp4 or Sp15 tumours plus regional lymph nodes could be completely curative, signifying initial spread of tumours via the lymphatics and only subsequently via the blood stream . On the other hand, resection en bloc of primary Sp22 tumours plus regional lymph nodes at a similar stage of primary tumour development was never curative, signifying early spread via the blood stream . Other studies showed that the metastatic potential of mammary carcinoma Sp4 was an innate characteristic of the tumour and not related to the tissue of implantation since in addition to metastasizing from the mammary pad it metastasized when implanted either s.c . or intradermally in a region devoid of mammary tissue . Furthermore, a rat sarcoma Mc7 showed a negligible tendency to metastasize when implanted either in the mammary pad or in the s.c . tissue, where it had been induced with methylcholanthrene.

J Immunol, 1979 Oct, 123(4), 1778 - 80
Rapid magnetic purification of rosette-forming lymphocytes; Owen CS et al.; High gradient magnetic separation, which as previously been shown effective in extracting erythrocytes from a flowing cell suspension, has been used to separate rosetted and unrosetted human peripheral blood lymphocytes . The hemoglobin in the sheep red cells used to form rosettes was first oxidizied to the paramagnetic methemoglobin form . Samples of 50 x 10(6) lymphocytes could be processed in 10 min under sterile conditions with greater than 90% purity of the rosetted cell fraction and maintenance of T cell function in mixed lymphocyte cultures.

Am J Pathol, 1979 Oct, 97(1), 17 - 41
alpha-Naphthyl acetate esterase activity--a cytochemical marker for T lymphocytees . Correlation with immunologic studies of normal tissues, lymphocytic leukemias, non-Hodgkin's lymphomas, Hodgkin's disease, and other lymphoproliferative disorders; Pinkus GS et al.; Cytochemical identification of T lymphocytes on the basis of alpha-naphthyl acetate esterase (NAE) activity was compared with immunologic markers for cell suspensions and/or cryostat sections of 113 specimens . Nonneoplastic tissues (peripheral blood, lymph nodes, spleens, tonsils, thymus, and pleural fluid) and specimens from various lymphoproliferative disorders, including acute and chronic lymphocytic leukemia, lymphosarcoma cell leukemia, hairy cell leukemia, non-Hodgkin's lymphomas of B-and T-cell types, and Hodgkin's disease, were evaluated . T (E-rosetting) cells demonstrated several patterns of NAE reactivity: 1) a strong globular reaction product, the most specific pattern for T-cell identification, 2) granular cytoplasmic staining, or 3) no reactivity . B lymphocytes revealed a granular pattern of NAE staining, were devoid of enzyme, or, in rare instances, exhibited strong NAE activity . Percentages of lymphoid cells with strong (globular) NAE activity closely paralleled T-cell (E-rosette) values in the majority of cases, with the best correlations observed for peripheral blood studies . However, discordant results were noted for some neoplastic and nonneoplastic tissues, including cases of T-cell lymphoma or leukemia . Markedly discrepant results were noted for thymic lymphocytes, most of which revealed E-rosette formation and weak or absent NAE activity . Lymph nodes involved by Hodgkin's disease demonstrated a heterogeneous pattern of staining in E-rosetting cells and in Reed-Sternberg variants . Cryostat section studies of reactive lymph nodes and nodular lymphomas demonstrated strong NAE staining in lymphoid cells of T-cell (interfollicular, internodular) areas, with little or no positivity in follicles or nodules (B-cell areas) . NAE staining patterns further suggested that T cells comprise part of the follicular cuff and possibly represent a minor population of some neoplastic nodules . Although NAE determinations do not represent a consistently reliable alternative to immunologic methods for T-cell identification, this easily applicable cytochemical marker is complementary to other techniques in assessing neoplastic or nonneoplastic tissues, particularly cryostat sections . (Am J Pathol 97:17--42, 1979).

J Immunol, 1979 Oct, 123(4), 1818 - 21
Presence of T cell-associated surface antigens on murine NK cells; Pollack SB et al.; The expression of T cell-associated surface antigens on natural killer (NK) spleen cells of C57BL/6 mice was evaluated by cytotoxic depletion experiments with alloantisera prepared against the Thy 1, Ly 1, Ly 2, Ly 5, Ly 6, and NK 1 antigens . The NK activity of these nonimmunized spleen cells for YAC-1 leukemia cells was dramatically reduced by antisera to the Ly 5 and NK 1 antigens . Variable results were obtained with anti-Ly 6 sera--certain pools of this antiserum decreased the NK activity, whereas other pools showed only negligible effects . The NK activity of the same cell suspensions was not affected by antisera to the Thy 1, Ly 1, and Ly 2 antigens . In parallel tests the T cell-associated cell surface antigens of alloimmune T killer cells were similarly evaluated by cytotoxic depletion experiments . In this case, the activity of these cells was consistently diminished by antisera to the Thy 1, Ly 2, Ly 5, and Ly 6 antigens, but not by antisera to the Ly 1 and NK 1 antigens . On this basis it was concluded that the NK cells expressed a restricted subset of T cell-associated alloantigens and therefore may have been derived from the T cell lineage of lymphocytes.

J Clin Microbiol, 1979 Oct, 10(4), 533 - 7
Comparison of rates of virus isolation from leukocyte populations separated from blood by conventional and Ficoll-Paque/Macrodex methods; Howell CL et al.; One hundred fifty-two blood specimens, largely from immunocompromised patients, were collected in heparinized Vacutainer tubes and divided into paired aliquots of equal volume . Buffy-coat preparations, containing mixed leukocyte and separate mononuclear and polymorphonuclear leukocyte populations were obtained by treatment of blood with conventional and Ficoll-Paque/Macrodex (F-P/M) methods . The development of cytopathic effect in monolayers of WI-38 fibroblasts inoculated with cell suspensions derived from the two methods was used to assess virus infectivity . Twice as many virus isolations were obtained using F-P/M . Of those viruses isolated by both conventional and F-P/M, the development of cytopathic effect was more extensive using the latter method . Moreover, a greater variety of viruses was isolated using F-P/M method, as compared to the conventional method . The F-P/M method is no more time consuming than conventional procedures, is readily adaptable for use in the diagnostic virology laboratory, requires only minimal additional cost, and is a particularly suitable and effective means of monitoring viremia.

J Biochem (Tokyo), 1979 Oct, 86(4), 971 - 7
Probable sites of action of cyclic adenosine 3',5'-monophosphate in the induction of phosphodiesterase in Dictyostelium discoideum; Yamasaki F et al.; The sites of action cyclic adenosine 3',5'-monophosphate (cAMP) in phosphodiesterase {EC 3.1.4.17} induction in Dictyostelium discoideum were studied . When cAMP was added to the cell suspension from the start of the incubation, the effect of the cyclic nucleotide on the cellular enzyme-induction did not appear for 30 min, then occurred abruptly . From experiments on the addition of cAMP to the cell incubation mixture at various times, preparations for the synthesis of the enzyme appear to occur during the period from 20 min to 30 min after the start of the incubation . After the addition of cycloheximide at 30 min, the enzyme was degraded very rapidly . The half-life of phosphodiesterase was roughly 21 min in the presence of cAMP, and 12 min in its absence . The degradation rates became approximately the same on removing cAMP . When daunomycin and actinomycin D were added to cells previously stimulated with cAMP, phosphodiesterase was still synthesized at a higher rate than in cells not pretreated with cAMP . These results suggest that cAMP acts at two sites at least, i.e., on enzyme synthesis at the transcription level, and in suppressing the degradation of phosphodiesterase.

J Anat, 1979 Oct, 129(3), 541 - 59
Dissociation of adult mammalian heart into single cell suspension: an ultrastructural study; Nag AC et al.; Adult rat heart was dissociated into a single cell suspension by a perfusion technique which used 0.05% collagenase and 0.1% hyaluronidase in Krebs-Ringer phosphate buffer (KRP) . The non-muscle cells of the suspension were separated from the myocytes by centrifugation through 3% Ficoll solution in KRP with 0.01 mM Ca2+ . An approximately 90% pure suspension of isolated single muscle cells was obtained with this method . The effects of the successive steps in the dissociation procedure on the ultrastructure of the heart were studied by scanning and transmission electron microscopy . After 30 minutes of enzyme digestion, dissociation of the inner endothelial lining of the ventricle into single cells or small groups of cells became apparent . In addition, the underlying cardiac skeleton began to disintegrate and linear arrays of cardiac muscle cells were observed . After 45 minutes of enzyme digestion the number of released single cells was higher because of the separation of intercalated discs . The majority of non-muscle cells were by now dissociated from the surfaces of muscle cells . Widening of the lateral intercellular spaces between the myocardial cells was associated with separation of desmosomes . In some regions of the heart, intact desmosomes, fasciae adherentes and gap junctions were observed even though lateral intercellular spaces had widened greatly . The majority of myocardial cells had become separated from one another after 60 minutes of enzyme digestion . Separation of gap junctional sites took place in two ways: (1) by 'unzipping' them through enzyme action; (2) by tearing them mechanically . Gap junction remnants were sometimes observed in a vesiculated state within the cell . The dissociation of the heart was ineffective when perfused with media containing 1.0 or 2 mM Ca2+ . Alcian blue treatment after 60 minutes of enzyme digestion revealed that the basement membrane, and its accompanying collagen fibrils, was still present on the plasma membrane of dissociated single cells . The isolated myocardial cells retained their normal morphological characteristics . This study has enabled us to understand in detail how dismantlement of highly ordered adult cardiac tissue into a single cell suspension takes place . Cell suspensions of this type should be invaluable in the study of metabolic and synthetic activities in adult myocardial cells.

Biochim Biophys Acta, 1979 Sep 21, 556(2), 278 - 91
Biochemical and ultrastructural study of the disruption of blood platelets by streptolysin O; Launay JM et al.; The membrane-damaging protein toxin, streptolysin O, proved highly lytic on human, guinea-pig and rabbit platelets . About 15 molecules of toxin were sufficient to lyse one cell . Platelet disruption was assessed by electron microscopy, clearing of cell suspensions and assay of lactate dehydrogenase, serotonin, monoamine oxidase and glutathione peroxidase released in the extracellular fluid . This egress reflected the damage of both plasmic and organelle membranes . A quantitative study of lactate dehydrogenase and serotonin liberation taken as respective markers of the cytosol and dense bodies was undertaken as a function of toxin concentration . No platelet aggregation or shape change was elicited by streptolysin O . The ghosts resulting from platelet lysis retained properties of the native membrane such as aggregability and serotonin uptake . Dense bodies were easily separated after gentle disruption of the plasmic membrane by small amounts of toxin . Platelet lysis by streptolysin O proved a useful procedure for the determination of protein content, enzyme activities and serotonin assay on the same lysate in contrast to usual methods.

World J Surg, 1979 Sep 20, 3(5), 641 - 50
Heterotransplantation of human gastric carcinomas into nude mice; Nakatani K et al.; A total of 33 specimens of human gastric carcinoma were used for transplantation into nude mice . Initital tumor "take" was accomplished in 15 of the 33 tumors, and the transplantability rate was 45.5% . Transplantability correlated with histologic type, but not with clinical stage or Borrmann's classification . The transplantability rate of differentiated carcinomas, such as well-differentiated tubular adenocarcinoma, moderately differentiated tubular adenocarcinoma, and papillary adenocarcinoma was greater than that of poorly differentiated tumors, such as poorly differentiated adenocarcinoma and mucinous adenocarcinoma . The growth patterns of transplanted tumors were divided into 3 types: rapid, slow, and persistent . There were no specific relationships between growth pattern and histologic type . All histologic types, except signet ring cell carcinoma, could be transplanted serially . Tumor growth became rapid after serial transfer . However, the original histology of these tumors was unchanged . No invasion or metastases were encountered . Intraperitoneal injection of a tumor cell suspension, prepared from subcutaneous transplants of a poorly differentiated adenocarcinoma of Borrmann type III, grew in an ascites form, with invasion and metastasis . Ascitic fluid accumulated within 3--6 weeks after injection . Subsequently, intravenous injection of ascites fluid produced metastases in nude mice . The histology of the subcutaneous tumor was similar to that of the original tumor from the patient.

Biochem J, 1979 Sep 15, 182(3), 697 - 705
Mechanism of the stimulation of serine and alanine transport into isolated rat liver cells by bicarbonate ions; McGivan JD; 1 . Bicarbonate ions stimulate the transport of serine and alanine into isolated hepatocytes . 2 . The effect of bicarbonate is to increase the Vmax . of the transport process without changing the apparent Km . 3 . The intracellular pH was estimated from the distribution of the weak base methylamine and the weak acid 5,5'-dimethyloxazolidine-2,4-dione (DMO) across the plasma membrane . 4 . The addition of bicarbonate to a cell suspension caused the internal pH to become more acid . 5 . The initial rate of serine, alanine and glycine transport was a linear function of the initial difference in pH across the membrane . 6 . It is concluded that bicarbonate activates the transport of these amino acids primarily by increasing the pH difference across the plasma membrane . 7 . It is suggested that the uptake of serine together with Na+ ions occurs in exchange for H+ ions, which are translocated outwards on the same carrier system . Some preliminary evidence consistent with this model is presented.

Biochem J, 1979 Sep 15, 182(3), 687 - 96
Quantitative analysis of proton-linked transport systems . The lactose permease of Escherichia coli; Booth IR et al.; Evidence is presented that lactose uptake into whole cells of Escherichia coli occurs by symport with a single proton over the range of external pH 6.5--7.7 . The proton/lactose stoicheiometry has been measured directly over this pH range by comparison of the initial rates of proton and lactose uptake into anaerobic resting cell suspensions of E . coli ML308 . Further, the relationship between the protonmotive force and lactose accumulation has been studied in E . coli ML308-225 over the range of external pH 5.9--8.7 . At no point was the accumulation of the beta-galactoside in thermodynamic equilibrium with the protonmotive force . It is concluded that the concentration of lactose within the cell is governed by kinetic factors rather than pH-dependent changes in the proton/substrate stoicheiometry . The relevance of these findings to the model of pH-dependent proton/substrate stoicheiometries derived from studies with E . coli membrane vesicles is discussed.

Biochim Biophys Acta, 1979 Sep 3, 586(3), 453 - 63
Stimulation of de novo synthesis of L-phenylalanine ammonia-lyase in relation to phytoalexin accumulation in Colletotrichum lindemuthianum elicitor-treated cell suspension cultures of french bean (Phaseolus vulgaris); Dixon RA et al.; (1) The regulation of the accumulation of the isoflavonoid-derived phytoalexin phaseollin in cell suspension cultures of Dwarf French Bean (Phaseolus vulgaris/ has been investigated . (2) An elicitor preparation from cell walls of Colletotrichum lindemuthianum, the causal agent of anthracnose disease of French bean, caused a marked accumulation of phaseollin in the cultures . The elicitor induced phaseollin accumulation to a level of 60% that obtained with the artificial elicitor autoclaved ribonuclease A and was maximally active at a concentration (weight basis) of at least 50 times lower than required for maximal response to ribonuclease . (3) Elicitor preparations from cell walls of Phytophthora megasperma var . sojae, a fungal pathogen of soybean, and Botrytis cinerea, the common grey mould, were much less effective than the C . lindemuthianum wall-released elicitor . (4) There was a marked but transient increase in the extractable activity of phenylalanine ammonia-lyase, the enzyme catalysing the first reaction in the biosynthesis of phaseollin from L-phenylalanine, in response to the elicitor from C . lindemuthianum . (5) Comparative density labelling with 2H from 2H2O indicated that the elicitor stimulates de novo synthesis of phenylalanine ammonie findings provide the basis of a scheme for elicitor induction of phytoalexin accumulation.

J Lipid Res, 1979 Sep, 20(7), 914 - 8
Measurement of cholic acid synthesis and secretion by isolated rat hepatocytes; Whiting MJ et al.; Liver cells isolated from normal and cholestyramine-treated rats were incubated as cell suspensions for up to 4 hr in a simple, defined medium . The bile acid concentration in cells plus cell medium was determined by gas-liquid chromatography . Normal hepatocytes synthesized cholic acid at an initial rate of 0.25 nmol/mg cell protein per hr, which is comparable to rates reported from in vivo methods . This rate was increased more than 4-fold when rats were fed a cholestyramine-containing diet for 7 days prior to liver cell isolation . Although cholic acid was secreted into the cell medium during the incubation, it could not be assayed reliably by the hydroxysteroid dehydrogenase assay method, contrary to the reports of Anwer et al . 1975 . Biochem . Biophys . Res . Commun . 64: 603 and Gardner and Chenouda 1978 . J . Lipid Res . 19: 985.

Am Rev Respir Dis, 1979 Sep, 120(3), 541 - 5
The effect of hyperoxia on migration of alveolar macrophages in vitro; Bowles AL et al.; There is in vitro evidence to support the notion that directed migration (chemotaxis) is involved in the recruitment of alveolar macrophages in vivo . Because O2 is widely used in the treatment of pulmonary diseases, we examined the effect of hyperoxia on migration of guinea pig alveolar macrophages in vitro . Migration was measured in blind-well chambers incubated in either room air or hyperoxia . N-formyl-methionyl-phenylalanine was used to stimulate random migration and to produce directed migration . Migration was quantified by counting the number of mononuclear cells per oil immersion field that had migrated completely through a polycarbonate filter with 5-micrometer pores . The average PO2 in the cell suspensions incubated in room air was 100 mm Hg . In the hyperoxic environments, the average PO2 at 1 h was 260 mm Hg, whereas at 2 and 3 h, it was 410 and 425 mm Hg, respectively . In 6 separate experiments, there was no significant difference between the mean response to N-formyl-methionyl phenylalanine in hyperoxia and in room air after 1 h of incubation . After 2 and 3h of incubation, however, the response in hyperoxia was significantly (P less than 0.002) lower than that in room air . The decreased response in hyperoxia did not appear to result from loss of viability of responding cells, diminished adherence of cells to the filters, loss of activity of N-formyl-methionyl phenylalanine exposed to high PO2, or failure of the cells to exhibit directed migration . Instead, it appeared that hyperoxia decreased the response of alveolar macrophages primarily by impairing random migration.

Am J Physiol, 1979 Sep, 237(3), H348 - 52
Application of an isolated heart model to investigate blood-oxygen delivery; Rand PW et al.; To avoid the compensatory hemodynamic responses, which have limited interpretation of hemoglobin-oxygen affinity modifications in animal experimentation, an isolated blood-perfused rabbit heart model providing metabolic, functional, and vectorcardiographic measurements has been developed . Fixed-flow perfusions of unchanged or affinity-modified red blood cell suspensions were carried out to assess the benefits of high affinity during hypoxic hypoxia and of low affinity during posthypoxic recovery . Using fully saturated suspensions, the influence of affinity level during restricted flow and reperfusion was also studied . Higher myocardial oxygen consumption (MVO2) was associated with high-affinity blood during mild hypoxia and low-affinity blood during posthypoxic recovery . At low flows, heart rate and MVO2 tended to be lower in high-affinity perfusions, and to recover more completely during low-affinity reperfusions . Ventricular function, vectorcardiographic patterns, and lactate levels were affected by hypoxia and ischemia, but not by level of affinity . The relevance of these observations to the therapeutic potential of hemoglobin-oxygen affinity modification is discussed.

Pflugers Arch, 1979 Sep, 381(3), 281 - 5
45Ca2+ uptake by dispersed pancreatic islet cells: effect of D-glucose and the calcium probe, chlorotetracycline; Sehlin J et al.; Uptake of 45Ca2+ was studied in dispersed pancreatic islet cells from non-inbred ob/ob-mice . Like whole islets the dispersed cells responded to 20 mM D-glucose with a markedly increased 45Ca2+-labeling of both the lanthanum-nondisplaceable and the lanthanum-displaceable calcium pools . The pronounced effect of D-glucose could not be reproduced with 3-O-methyl-D-glucose, L-glucose, D-mannose, L-leucine, or D-leucine; however, 45Ca2+ uptake was greater in the presence of L-leucine as compared with D-leucine . 45Ca2+ uptake by dispersed cells or whole islets was stimulated severalfold by 100 microM or more chlorotetracycline . At the concentration of only 10 microM, chlorotetracycline had no effect on whole islets and partially inhibited 45Ca2+ uptake by the dispersed cells . The ability of D-glucose to stimulate 45Ca2+ uptake by islets or dispersed cells remained in the presence of 10 microM chlorotetracycline . Islet cell suspensions apparently represent a valid model for studying how Ca2+ interacts with the cells . However, when using chlorotetracycline as fluorescent Ca2+ probe, attention must be paid to it potential ionophoric activity . At only 10 microM, the drug seems to monitor a peripheral pool of Ca2+, some of which may reside in normal transport channels.

Exp Hematol, 1979 Sep, 7(8), 416 - 24
Engraftment of bone marrow transplants in W anemic mice measured by electronic determination of the red blood cell size profile; Wiktor-Jedrzejczak W et al.; Defective stem cells of WBB6F1-W/Wv mice produce macrocytic red blood cells (RBCs); stem cells of WBB6F1-+/+ mice produce normocytic RBCs . Utilization of the Coulter counter channelyzer permitted good dissociation between the size distribution of populations of +/+ and W/Wv RBCs . Peaks (mean cell volumes) for +/+ and W/Wv RBCs have been determined to be between the 30th and 40th channel and 50th and 60th channel, respectively . Variability of profiles for individual mice of both genotypes did not exceed the variability of separate determinations of the same cell suspension from a single mouse . Admixture (approximately 15%) of either type of erythrocytes could be quantitatively detected by this method . One week after transplant of 10(7) +/+ marrow cells into W/Wv recipients, 25% of donor type erythrocytes were detected . Eighteen days post-graft, concentration of +/- normocytes exceeded the concentration of macrocytes in the W/Wv recipients' circulation . Approximately 45 days post-transplant, the proportion of macrocytes decreased below the 10% detectable level . Calculation of the daily RBC production rate during repopulation and estimation of the number of RBCs produced by a single hematopoietic colony were determined . The RBC size profile was found to be a convenient method for studying the effect of implantation of W/Wv marrow into lethally irradiated +/+ mice . This method proved suitable for repetitive determination of the size population in individual transplanted mice.

J Natl Cancer Inst, 1979 Sep, 63(3), 587 - 92
Relationship between monocytosis and T-lmphocyte function in human cancer; Wood GW et al.; This study was designed to: 1) determine the relative number of monocytes in mononuclear cell suspensions derived from the peripheral blood of cancer patients and 2) ascertain if any relationship existed between the numbers of monocytes in those cell suspensions and T-lymphocyte function . Monocytes were quantitated by morphology verified by phagocytosis of antibody-coated erythrocytes . A significant difference (P less than or equal to 0.01) existed between the number of monocytes in suspensions from normal individuals (26.2 +/- 4.3) and cancer patients (38.0 +/- 13.4) . The cancer patients were divided into 2 groups: 1) those who exhibited normal in vitro T-cell responses to phytohemagglutinin and 2) those in whom responses were significantly suppressed . The mean number of monocytes in suspensions from the cancer patient group with normal responses was 29 +/- 9, whereas that from the cancer patients with suppressed responses was 47 +/- 11, a highly significant difference (P less than or equal to 0.01) . Therefore, the study demonstrated two things: 1) Mononuclear cell suspensions derived from cancer patients exhibited significant monocytosis relative to those from normal individuals and 2) a strong correlation existed between monocytosis and suppressed T-lymphocyte function in vitro.

J Immunol, 1979 Sep, 123(3), 1356 - 61
In vitro antibody response to influenza virus . I . T cell dependence of secondary response to hemagglutinin; Anders EM et al.; A good secondary IgG response to the hemagglutinin (HA) of influenza virus has been obtained in vitro in Marbrook-type cultures of influenza-primed mouse spleen cell suspensions stimulated with inactivated influenza virus . Anti-HA antibody was quantitated by a solid phase radioimmunoassay (RIA) by using purified HA as substrate . The T dependence of this secondary response was shown by depletion of T cells and reconstitution with a source of primed or unprimed T cells . The help given by T cells primed to the homologous virus was many times greater than that given by unprimed T cells, although the latter was significant . The system described will allow investigation of the specificity requirements of helper T cells engaged in the anti-HA response.

J Lab Clin Med, 1979 Sep, 94(3), 414 - 20
A method for obtaining human bone marrow specimens enriched for myeloblasts and promyelocytes; Preisler HD et al.; A simple method has been developed for obtaining specimens of human marrow which are enriched for myeloblasts and promyelocytes . The erythrocytes are lysed, the marrow is incubated with iron particles, and the cells that phagocytize the iron are removed with a powerful magnet . The marrow is then subjected to a density-cut centrifugation using Ficol-Hypaque with a density of 1.084 gm/mm3 . The cells that do not enter the Ficol-Hypaque are removed from the surface and studied . The proportion of myeloblasts and promyelocytes in this subpopulation of cells exceeds 50% . Total recovery of these immature myeloid progenitor cells is 50% of that in the original marrow specimen . This method has been used for cell suspensions containing as many as 10(9) cells . Cells prepared using this method incorporate 3H-TdR, 3H-UR, and 3H-Leu at a higher rate than the unseparated specimens and have a cloning efficiency of 2.0% to 19.4% compared with 0.1% to 2.17% for the unseparated marrows.

Blood, 1979 Sep, 54(3), 703 - 12
Hand-mirror cell leukemia associated with mental retardation: immunologic, chromosome, and morphological studies; Stern R et al.; Cycochemical, morphological, immunologic, and cytogenetic studies were carried out on hand-mirror cells (HMC) from a mentally retarded patient with a constitutional chromosome abnormality, 46,XX,r(21), and acute lymphoblastic leukemia . Scanning electron and differential interference contrast microscopy showed microspikes on the uropodia, but little evidence of cellular motility, despite formation and disappearance of individual uropodia in cell suspensions . The cells rosetted with sheep erythrocytes, suggesting T-cell origin . Cells derived from the bone marrow (80% HMC) showed a high degree of polyploidy (60%) and a bimodal chromosome number of 49 (49,XX,+10,-21, +3 rings) and 94 (6 no . 10, 3 no . 18, 2 no . 21 chromosomes, 3 ring chromosomes, plus 4 copies of each other chromosome).

Z Naturforsch {C}, 1979 Sep-Oct, 34(9-10), 704 - 8
A model mechanism for the enzymatic synthesis of lupin alkaloids; Wink M et al.; A crude enzyme preparation obtained from cell suspension cultures of Lupinus polyphyllus catalyzes the pyruvate dependent conversion of cadaverine into the tetracyclic lupin alkaloids . As the first reaction product 17-oxosparteine could be identified by gas-liquid chromatography and mass spectroscopy . In some experiments sparteine was found additionally . A participation of diamine oxidase could be ruled out . The cadaverine-pyruvate transaminating enzyme system (17-oxosparteine synthase) catalyzes the formation of 17-oxosparteine from three cadaverine units without releasing free intermediates . These results are inconsistent with the hypothetical mechanism thus far formulated for the lupin alkaloid biosynthesis . A new enzymatic model mechanism is proposed regarding both the results of the enzymatic experiments and those of the in vivo tracer studies.

Am J Physiol, 1979 Sep, 237(3), R132 - 8
Kinetics of bicarbonate/chloride exchange in dogfish erythrocytes; Obaid AL et al.; A stopped-flow rapid reaction apparatus was used to monitor changes in extracellular pH in dogfish (Mustelus canis) erythrocyte suspensions under conditions where dpH/dt was determined by the rate of HCO3-/Cl- exchange across the red cell membrane . Experiments were performed on erythrocytes suspended either in their own plasma or in elasmobranch Ringer solution over a range of temperatures from 5 to 35 degrees C . The exchange fluxes at 25 degrees C for red blood cells suspended in their own plasma (2.03 nmol/cm2-s) or in Ringer solution (2.00 nmol/cm2-s) are not significantly different and can be compared to those obtained under similar conditions for human red cell suspensions (0.910 nmol/cm2-s) . The flux for dogfish erythrocytes suspended in Ringer solution was reduced by 80% after exposure of the cells to SITS . An Arrhenius plot of the exchange rate constant yielded an activation energy of about 13.2 kcal/mol . We conclude that 1) plasma has no inhibitory effect of HCO3-/Cl- exchange across the dogfish erythrocyte membrane or on activity of intraerythrocyte carbonic anhydrase, 2) HCO3-/Cl- exchange probably occurs via the same mechanism in fish and mammalian erythrocytes, and 3) the conversion of plasms HCO3- to CO2 in dogfish can be catalyzed by intraerythrocyte carbonic anhydrase.

Crit Care Med, 1979 Sep, 7(9), 391 - 5
Automated method for determination of oxygen equilibrium curves of red cell suspensions under controlled buffer conditions and its clinical applications; Asakura T; The accurate determination of the oxygen equilibrium curve (OEC) of whole blood or red cell suspensions requires special considerations to avoid the secondary effects due to lactate formation, removal of carbon dioxide, use of anticoagulants, etc . An automated apparatus has been constructed that can record the whole OEC of red cells within 20 min . The instrument also can be used to record the OEC of hemolysate . The pH, temperature, and PO2 are monitored constantly during the measurement . Using this instrument, the effects of pH, temperature, carbon dioxide, anticoagulants, and buffers on the OEC of normal fresh blood have been investigated . The OEC of normal blood, blood containing abnormal hemoglobin, or enzyme, were determined . The results were compared with those obtained using commercial OEC apparatuses.

J Biol Chem, 1979 Aug 25, 254(16), 7885 - 94
Synthesis and secretion of corticotropins, melanotropins, and endorphins by rat intermediate pituitary cells; Mains RE et al.; The synthesis and secretion of various intermediate pituitary proteins was studied by using dispersed intermediate pituitary cell suspensions . Control studies indicated that the isolated cells were obtained in good yield and that after more than 24 h in culture the isolated cells continued to synthesize a collection of proteins similar to those found in freshly extracted intermediate pituitary tissue . Rat intermediate pituitary cells synthesized a molecule (Mr = 30,000; called 30K) that contained antigenic determinants for beta-endorphin, gamma-lipotropin, corticotropin (ACTH), and 16K fragment (the NH2-terminal region of mouse tumor cell pro-ACTH/endorphin) . This 30K molecule, two high molecular weight forms of ACTH(13K and 20K), and 16K fragment were all shown to be glycoproteins . Continuous labeling and pulse-chase incubations were used to define the intracellular biosynthetic processing of the 30K molecule . After a 15-min pulse incubation the 30K molecule was the only labeled protein containing antigenic determinants for beta-endorphin, gamma-lipotropin, ACTH, or 16K fragment . A beta-lipotropin-like molecule served as a biosynthetic intermediate in the production of proteins similar to beta-endorphin and gamma-lipotropin . Methionine-enkephalin and alpha-endorphin were not major products in the intermediate lobe cells . Molecules similar to alpha-melanocyte-stimulating hormone and corticotropin-like intermediate lobe peptide (ACTH(18-39)) were also derived from the same 30K molecule; 20K ACTH served as a biosynthetic intermediate in this conversion . In rat intermediate pituitary cells ACTH(1-39) was not a major final product of the intracellular biosynthetic processing of the 30K molecule . The 30K molecule also served as a precursor to a protein similar to mouse tumor cell 16K fragment and related smaller proteins . With rat intermediate pituitary cells, pulse-chase experiments utilizing {35S}methionine demonstrated almost quantitative conversion of the 30K precursor into labeled proteins similar to beta-endorphin and alpha-melanocyte-stimulating hormone . In the absence of added secretagogues, small amounts of all of the smaller proteins derived from the 30K precursor were secreted coordinately into the culture medium.

Brain Res, 1979 Aug 3, 171(2), 225 - 37
Neurochemical and morphological studies of bulk isolated rat brain cells . II . Preparation of viable cerebral neurons which retain synaptic complexes; Huttner WB et al.; The bulk isolation from rat cerebral cortex of viable neurons retaining synaptic complexes is described . The basis of this procedure is to dissociate the neurons in situ from the surrounding glial cells . The glial structures that are normally adjacent to the neuronal cell body and to the proximal parts of the neuronal processes are largely destroyed by perfusion of the brain under special conditions . The most important of these conditions was found to be a hyperosmolar concentration of hexoses in the perfusion medium . In addition, the presence of collagenase and hyaluronidase in the perfusion medium and specific perfusate flow characteristics were required to produce the structural changes throughout the brain tissue . When the perfused brain was further dissociated into a cell suspension by mincing and sieving, isolated neurons were obtained, the majority of which retained the proximal parts of their processes . A novel feature of these neurons was the retention of synaptic boutons on the plasma membrane . Presynaptic terminals with mitochondria and vesicles as well as pre- and postsynaptic membranes and densities were observed on the isolated neurons . The neurons were fractionated to 90--95% purity using discontinuous Ficoll density gradient centrifugation with a liquid fluorocarbon as cushion . Highly purified, viable cerebral neurons retaining synaptic complexes are thus available in bulk for neurobiological studies.

Scand J Haematol, 1979 Aug, 23(2), 129 - 40
Effect of human serum from patients with haematological disorders on mouse pluripotent haemopoietic stem cells (CFU-S); Sawada U et al.; Sera from 25 individuals (9 healthy subjects, 6 patients with systemic lupus erythematosus, and 10 patients with a variety of haematological disorders) were tested for anti-CFU-S by incubating suspensions of mouse marrow cells with serum and then assaying the cell suspensions for their capacity to form spleen nodules in lethally irradiated mice . The sera from 2 patients (1 with a preleukaemic disorder and the other with a malignant 'histio'-lymphoproliferative neoplasm) had anti-CFU-S activity which behaved like antibodies, rather than like the non-specific cytotoxic activity found in various sera for heterologous tissues, which in the past has been attributed to 'natural antibodies' and which, in recent years, has, in some cases, been found to be related to activation of the alternative pathway of complement . The anti-mouse tissue activity in the sera of the 2 patients may be related either to cross-reactivities between certain mouse and human tissues or to cross-reactivities between exogenous agents such as bacteria and mouse tissues.

J Pharm Sci, 1979 Aug, 68(8), 1022 - 4
Myoinositol uptake by rat hepatocytes in vitro; Chen CP et al.; Myoinositol uptake by rat hepatocytes in vitro was studied . Adult rat hepatocytes were prepared by digestion of the perfused liver with collagenase . Cell suspensions were incubated with tritium-labeled myoinositol in pH 7.4 Krebs bicarbonate solution containing 1% gelatin at 37 degrees . 14C-Carbon-labeled polyethylene glycol was used as a marker of adherent extracellular fluid volume . Myoinositol uptake was demonstrable after 5 min of incubation, but no intracellular concentration in excess of that in the incubation medium was observed after 60 min of incubation . Uptake saturation over a wide myoinositol concentration range could not be demonstrated . Neither the omission of sodium ions nor the inclusion of ouabain suppressed the distribution ratio significantly . Metabolic inhibitors and lower temperatures also showed no effect . Hexoses, phlorizin or mannitol, exerted no observable effect on myoinositol uptake . The results indicated that myoinositol uptake by rat hepatocytes is probably a passive process.

Histochemistry, 1979 Aug, 62(2), 207 - 20
Studies of the binding of ethidium bromide to cells before and after enzyme treatment; Eisenhut M et al.; Binding of ethidium bromide (EB) to cells before and after HCl, pepsin and RNase treatment was investiaged by spectophotometric and fluorimetric methods . Binding isotherms, calculated with the McGheevon Hippel equation, taking EB as a non-interacting ligand, revealed the influcence of these treatments on the fluorescence characteristics of the cells which were measured by flow-through cytofluorimetry . Thus pepsin- and RNase-treated cells have a reduced intercalation capacity due to the loss of cytoplasmic RNA and RNA hydrolysis, respectively . HCl alone, or in association with pepsin, increased the equilibrium constant K considerably . Thus at low free EB concentrations the enchanced EB affinity of acid-pretreated cells generates a high fluorescence intensity, by comparison with treatments at neutral pH . This result contradicts the interpretation of high EB binding to acid pretreated cells which is commonly believed to be due to hydrolytic histone removal from potential intercalation sites . With increasing free EB concentrations the fluorescence intensities of RNase- and pepsin-treated cells culminate at the same level due to their amost identical intercalation capacities . Consequently, quantitative DNA analysis of pretreated cell suspensions with EB can only be performed if the alteration, induced by the pretreatment, has previously been studied.

Isr J Med Sci, 1979 Aug, 15(8), 693 - 7
Immunoelectron microscopy and immunocytochemistry in pathology, with special reference to immunoglobulin-producing cells; Gourdin MF et al.; The advantage of immunoelectron microscopy (immuno-EM) is that it allows the simultaneous detection of surface and internal cell components . The immunoperoxidase method is often more suitable than immunoferritin . There are no major difficulties in staining surface antigens by immuno-EM, provided sufficient amounts of pure antibodies are available for coupling to peroxidase . Prior fixation of cells, with faxatives that preserve the antigenicity of surface components, avoids ligand-induced alterations of the surface components . It is believed that, unlike the surface, intracellular antigens are difficult to stain by immuno-EM because of the poor penetration of conjugates into fixed cells; thus, various technical approaches have been proposed by workers involved in tissue immuno-EM . In fact, the method that we initially devised for the surface staining of fixed cell suspensions has proved to detect specifically intracellular immunoglobulins in B cells obtained from patients with proliferative diseases . Thus, conjugates do penetrate into fixed cells, although by an unknown mechanism . On this basis, it is possible to study both surface and intracellular immunoglobulins at the EM level and to determine the precise localization synthesis.

Arch Pathol Lab Med, 1979 Aug, 103(9), 433 - 6
Immunological studies in hairy cell leukemia; Davey FR et al.; Cytochemical and immunological studies were performed on tissues and mononuclear cell suspensions from ten patients with hairy cell leukemia . In all cases studied, tartrate-resistant acid phosphatase was noted within the cytoplasm of hairy cells (HCs) . In two thirds of the cases, alpha naphthyl acetate esterase was observed in HCs . In addition, HCs did not form spontaneous rosettes with sheep erythrocytes . A variable number of HCs displayed complement receptors . The nonspecific binding of conjugated immunoglobulin to HCs probably reflected the presence of a high concentration of Fc receptors on the HCs surface . In three cases, the conjugated immunoglobulin reacted predominantly to one light chain, thus suggesting the presence of a monoclonal immunoglobulin . In four of six cases, mononuclear cell suspensions of HCs demonstrated latex phagocytosis . In one case, HCs displayed resynthesis of surface membrane immunoglobulin, the presence of B cell antigen, and phagocytosis of latex . These findings suggest that HCs are distinctive and contain properties of both B lymphocytes and monocytes.

J Exp Med, 1979 Aug 1, 150(2), 205 - 17
In vitro model for natural tolerance to self-antigens . Inhibition of the development of surface-immunoglobulin-negative lymphocytes into T-dependent responsive B cells by antigen; Teale JM et al.; Neonatal and adult splenic cell suspensions were labeled with fluorescein isothiocynate-anti-Ig and fractionated into surface-immunoglobulin- (s-Ig) positive and s-Ig-negative subpopulations by the fluorescence-activated cell sorter . The subpopulations were then tested by splenic focus assay for both frequency and tolerance susceptibility of clonable 2,4,-dinitrophenol (DNP) precursors . It was shown that both adult, and neonatal, s-Ig-negative subsets contained clonable DNP-specific B-cell precursors . However, because these precursors result in fewer clones secreting IgG, they appeared to be less mature than the s-Ig-positive precursors . In the absence of helper T cells, it was found that exposure of s-Ig-negative lymphocytes to tolerogen during the process in which they were acquiring surface receptors resulted in nearly total abrogation of potential DNP clones . This finding provides compelling evidence for clonal abortion.

J Bacteriol, 1979 Aug, 139(2), 560 - 4
Role of lithium ions in proline transport in Escherichia coli; Kayama-Gonda Y et al.; Mechanisms of Li+ stimulation of proline transport were studied in cells of Escherichia coli 7 and NR70, a mutant of strain 7 lacking adenosine triphosphatase (EC 3.6.1.3) . An electrochemical potential difference of Li+ induced in an inward direction of energy-depleted cells caused a transient uptake of proline depending on the driving force provided . When proline was added to unbuffered cell suspensions under anaerobic conditions, the medium was found to be acidified only in the presence of Li+ but not in the presence of Na+ or K+ . This acidification was abolished by the addition of a permeant anion, SCN-, to the medium containing Li+, but this was not demonstrated with cells of a mutant strain deficient in a carrier protein specific for proline . These results support the assumption that proline is taken up by a mechanism of Li+-proline cotransport in E . coli.

J Biol Chem, 1979 Jul 25, 254(14), 6560 - 7
Comparison of formation, activation, and nuclear translocation of receptor . estradiol (R . E2) complex at 0 degrees C and 37 degrees C in intact uterine cells; Traish AM et al.; The present study was undertaken to establish whether molecular events leading to binding, transformation-activation, and nuclear translocation of cytoplasmic uterine estrogen receptor described for cell-free systems also occur in intact uterine cells . Cell suspensions were incubated at 0 degrees C or 37 degrees C with estradiol (E2) and specific binding to intracellular receptors was measured . The data demonstrate that saturation of specific estrogen binding sites occurs within 60 min at 37 degrees C and within 22 h at 0 degrees C, with a total of approximately 24,000 to 30,000 receptor sites per cell . At equilibrium, the total number and subcellular distribution of receptor . estradiol (R . E2) complexes formed in cells incubated at 0 degrees C or 37 degrees C were identical . Scatchard analysis of the equilibrium binding data yielded the same association constants for cytoplasmic and nuclear R . E2 formed in intact cells incubated at either temperature . Sucrose density gradient analysis of nuclear and cytoplasmic R . E2 formed in intact cells at 0 degrees C or 37 degrees C showed that at both temperatures, the nuclear R . E2 had a 5 S sedimentation coefficient; at both temperatures, a 5 S cytosol R . E2 was detected; only in the 0 degrees C incubation, an additional 4 S cytosol R . E2 was found . These results suggest that the molecular interactions regulating the dynamics of estrogen binding in the intact cell are similar at both physiological and low temperatures.

Biochim Biophys Acta, 1979 Jul 18, 585(4), 630 - 42
The dark respiration of Anacystis nidulans . Production of HCN from histidine and oxidation of basic amino acids; Pistorius EK et al.; The basic amino acids, L-arginine, L-lysine, LO-irnithine, and to a lesser extent L-histidine, strongly stimulate the O2 uptake of cell suspensions of the blue-green alga or cyanobacterium anacystis nidulans . In the case of L-histidine, the extra O2 consumption is associated with the formation in vivo of small amounts of HCN, particularly in an atmosphere of O2 . The enzyme responsible for both the stimulated O2 uptake with the basic amino acids and the formation of HCN from histidine has been isolated and identified as an L-amino acid oxidase specific for the basic amino acids . The purification (15 000-fold) of this enzyme is described . The isolated enzyme is inhibited by o-phenanthroline, which has a similar inhibitory effect on the O2 uptake of cell suspensions with (and without) added amino acids . The basic amino acid oxidase, which is not inhibited by HCN, can be regarded as an 'alternate' oxidase in A . nidulans . An oxidase sensitive to HCN is apparently also operative . At high concentrations of lysine or arginine added HCN can almost double the initial rate of O2 consumption of cell suspensions . This can be attributed to the inhibition of catalase by HCN . At low concentrations of the amino acids, and with more prolonged incubation time, HCN becomes inhibitory . One interpretation could be that the HCN-sensitive terminal oxidase is also involved in the extra O2 uptake elicited by the basic amino acids, but other interpretations are possible . The extra O2 uptake elicited by histidine is almost completely inhibited by HCN, which is consistent with the finding that histidine is a relatively poor substrate for the basic amino acid oxidase.

Tohoku J Exp Med, 1979 Jul, 128(3), 273 - 84
Filtrability and flow characteristics of leukemic and non-leukemic tumor cell suspension through polycarbonate filters in relation to hematogenous spread of cancer; Khato J et al.; Tumor cell suspension was filtered through Nuclepore filters of various pore diameters (5.4, 7.9 and 9.3 micron) with positive pressure from 5 to 60 cmH2O at 37 degrees C . The mean diameters of tumor cells of 6 strains ranged from 10.6 to 13.6 micron . Cell suspension of each tumor strain was filtered with characteristically different time . No significant difference was observed among tumor strains in the percentage of cells filtered . The cell viability was almost unchanged by filtration . The filtration time was considered to indicate the passing ability of tumor cells through capillary pores . Leukemic cells such as DBLA 1, DBLA 6 and L 1210 were relatively small in diameter and possessed a high passing ability compared with other non-leukemic tumor cells such as Yoshida sacroma, AH 109A and AH 100B . The relationship between pressure and flow rate of the cell-free solution was linear, while the pressure-flow rate curves of the tumor cell suspension were convexed to the pressure-axis at low pressure and became linear over the pressure of the yield point . Rheologically, the yield point and the reciprocal of the slope indicate structural viscosity and apparent viscosity of the cell suspension, respectively, they are considered to reflect the rheological properties of tumor cells . Comparing these parameters of the curves in filters of different pore diameters, the viscosity of leukemic cells appeared to be the lowest and the structural viscosity of AH 100B cells was the highest among the tumor strains examined . The distribution and frequency of metastases following intravenous transplantation of these tumor cells suggested that the passing ability of tumor cells plays an important role in organ preference of hematogenous metastasis and leukemic state in leukemia.

Br J Cancer, 1979 Jul, 40(1), 81 - 8
Assays of drug sensitivity for cells from human tumours: in vitro and in vivo tests on a xenografted tumour; Bateman AE et al.; A human tumour which grows as a xenograft in immune-suppressed mice and forms colonies in vitro has been used to test the correlation between 2 methods of exposure of human tumour cells to chemotherapeutic agents . In vivo exposure to drugs was achieved by injection of tumour-bearing mice with each of 8 cytotoxic agents . For the in vitro exposure, cell suspensions were incubated for 1 h with the same series of drugs . The survival of tumour clonogenic cells was assayed in vitro after either treatment or dose-response curves were obtained . The 8 drugs were ranked according to their in vivo effect at doses equitoxic to mice, and according to their in vitro effect at concentrations designed to approximate to levels of drugs in human plasma . The ranks for in vivo and in vitro exposure correlated well.

J Lab Clin Med, 1979 Jul, 94(1), 133 - 43
The measurement of erythrocyte deformability using micropore membranes . A sensitive technique with clinical applications; Leblond PF et al.; This article describes a positive-pressure filtration technique using low pore-density, 3 microns pore-diameter polycarbonate membranes employed to evaluate erythrocyte deformability in a clinically oriented hematology laboratory . Mean erythrocyte resistance to filtration was expressed by a numerical index which takes into account both the initial resistance of dilute red cell suspensions to passage across the membrane and the relative pressure rise observed after filtration of 30 ml of the same suspension (3 . 10(8) cells) . The resistance index of 99 blood samples obtained from 88 healthy adult volunteers ranged between 1.4 and 2.9, with normal Gaussian distribution and mean of 2.04 . Values obtained on similarly prepared samples from 20 patients with various hemolytic anemias always fell outside this range, indicating a reduced deformability in every case . The existence of a strong positive correlation was found between the resistance index and the degree of reticulocytosis in these patients . This method appears more sensitive than previously described filtration techniques in detecting the presence of small numbers of poorly deformable erythrocytes in vivo, while being more practical and statistically more significant than the micropipette elastimetry technique . Our results, however, raise a new question concerning the role of reticulocytes in the evaluation of red cell deformability on blood samples from patients with hemolytic anemia.

Int J Radiat Biol Relat Stud Phys Chem Med, 1979 Jul, 36(1), 65 - 73
Radiation-induced DNA strand breaks and their repair in the developing rat brain; Cerda H et al.; Rats, 5, 10 or 25 days old, were 60 Co gamma irradiated . The induction of DNA strand breaks was studied after killing the rats within 1 min after irradiation, and the repair of the induced breaks after various intervals up to 180 min . Cell suspensions were prepared from the brain and samples were transferred into alkaline solutions . The fraction of DNA remaining double-stranded after 30 min alkali treatment was estimated after separation of single- and double-stranded DNA on hydroxylapatite . The amount of DNA strand breaks induced per Gray (1--8 Gray) was found to be in accordance with earlier in vivo studies of the mouse small intestine and mouse spleen . The DNA strand breaks in the rat brain induced by 4 Gray 60Co gamma irradiation were repaired 30 min after irradiation in all age groups studied.

Am J Pathol, 1979 Jul, 96(1), 257 - 77
Acid alpha-naphthyl acetate esterase activity in human neoplastic lymphoid cells . Usefulness as a T-cell marker; Knowles DM 2nd et al.; Previous studies have shown that a distinctive pattern of acid alpha-naphthyl acetate esterase (ANAE) activity (focal reaction product) characterizes normal human peripheral blood and tissue T lymphocytes but is absent from thymocytes and certain mitogen-stimulated T-cell blasts . In the present study mononuclear cell suspensions prepared from the peripheral blood and tissue specimens of 35 patients with lymphoid malignancies were simultaneously analyzed for surface immunoglobulin, sheep erythrocyte rosette formation, Ia antigens, and ANAE activity . The neoplastic cells from 16 patients with Ia+ SIg+ E- (B cell) malignancies, 4 patients with Ia+ SIg- E- (non-B, non-T) acute lymphoblastic leukemia, and 3 patients with Ia- SIg- E- (null cell) malignancies failed to exhibit ANAE activity . The neoplastic cells from 5 patients with Ia- SIg- E+ (T cell-derived) malignancies, including three cutaneous lymphomas, displayed characteristic T-pattern positivity, and in each case the percentage of E+ and ANAE+ cells was comparable . The neoplastic cells from 4 patients with Ia- SIg- E+ (T cell-derived) acute lymphoblastic leukemia were ANAE- . The expression of ANAE activity in T cell-derived malignancies may parallel its expression in the stages of normal T-cell differentiation and may prove to be a useful marker with which to sort out T-cell phenotypes.

J Clin Invest, 1979 Jul, 64(1), 72 - 82
Neutropenia in three patients with rheumatic disorders . Suppression of granulopoiesis by control-sensitive thymus-dependent lymphocytes; Bagby GC Jr et al.; A man with polymyalgia rheumatica (patient 1) and two patients (2 and 3) with Felty's syndrome had neutropenia at the time of diagnosis . Bone marrow samples in each patient were cellular but showed an "arrest" of granulocyte maturation at the myelocyte stage . Agar colony growth of marrow cells from each patient was subnormal but increased after removal of sheep erythrocytes rosette-forming cells (thymus-dependent {T} cells) from marrow cell suspensions before culture . Preincubation of marrow cells with cortisol also enhanced colony growth . Maximum enhancement with cortisol occurred at 1 mM (patient 1), 1 microM (patient 2), and 10 nM (patient 3) . Cortisol failed to enhance colony growth after removal of T cells from marrow cell suspensions . Peripheral blood lymphocytes (PBL) and PBL-conditioned medium from all three patients inhibited colony growth of normal human marrow cells . Cortisol treatment of PBL or T depletion from PBL abrogated the inhibition in coculture and with conditioned medium . Prednisone therapy resulted in the disappearance of suppressor T-cell function concomitant with hematologic improvement in patients 2 and 3, but suppressor T cells persisted in patient 1, who did not respond to prednisone . We conclude that cortisol-sensitive T lymphocytes inhibited granulopoiesis in vitro probably by elaboration of a soluble factor or factors . Our results suggest (a) that neutropenia in these patients resulted, at least in part, from T-cell suppression of granulopoiesis, (b) that the effectiveness of prednisone therapy was a result of its inhibition of suppressor T cells, and (c) that responses to glucocorticoid therapy may be predicted in such patients with the agar culture technique and cortisol dose response in vitro.

Proc Natl Acad Sci U S A, 1979 Jul, 76(7), 3495 - 8
Attempt to immunize guinea pigs against L2C leukemia with leukemia cells inactivated by gamma irradiation; Gross L et al.; In previous studies, intradermal inoculation of small doses of L2C leukemic cell suspensions into strain 2 guinea pigs induced immunity against challenging reinoculation with leukemic cells; however, 50% of the guinea pigs developed leukemia in the course of immunization . We have now attempted to induce immunity by inoculation of L2C leukemic cells inactivated by in vitro gamma irradiation ranging from 750 to 8000 rads (1 rad = 0.01 gray) . In preliminary experiments, irradiation with 750 to 2750 rads had no significant effect on leukemogenic potency of leukemic cells; however, doses exceeding 3000 rads inactivated the leukemogenic potency of L2C cells . Eighty-nine guinea pigs that survived intradermal, subcutaneous, or intraperitoneal inoculations with irradiated (1000-8000 rads) L2C cells were subsequently challenged by reinoculation with nonirradiated leukemic cells, and 83 of them (93%) developed leukemia . L2C leukemic cells contain spherical particles, about 103 nm in diameter; it is reasonable to assume that these particles represent the causative virus responsible for the development of L2C leukemia . Inactivation of leukemogenic potency of L2C leukemic cells by gamma irradiation in vitro does not necessarily imply that the virus particles consistently present in these cells were also inactivated . In previous experiments carried out on mouse leukemia, doses exceeding 1,000,000 rads were needed in order to inactivate the mouse leukemia virus in vitro.

Cancer Lett, 1979 Jul, 7(2-3), 103 - 8
Excision of DNA damage arising from chemicals of different carcinogenic potencies; Dipple A et al.; Primary cultures of mouse embryo cells are more efficient in excising DNA-carcinogen adducts resulting from exposure to either 7-bromomethylbenz-{alpha}anthracene or the more carcinogen 7-bromomethyl-12-methylbenz{alpha}anthracene than are mouse L 929 cell suspension cultures . However, within each of these systems, the excisabilities of the adducts formed by either bromo-compound are similar, so differences in carcinogenic potency of the compounds cannot be attributed to differences in the excisability of their DNA-adducts.

Cancer, 1979 Jul, 44(1), 258 - 63
Pseudolymphoma of breast; Fisher ER et al.; A lymphoid infiltrate in the breast of a 77-year-old woman exhibited histological features warranting a diagnosis of pseudolymphoma . Detection of surface markers on cell suspensions of the lesion revealed approximately equal numbers of B aand T cells and kappa and lambda light chains in the immunoglobulins of the former . This represents ancillary evidence that is consonant with the pseudolymphomatous nature of the infiltration . Recognition of pseudolymphoma of the breast as an entity appears significant from practical and theoretical standpoints and is relevant to considerations concerning the incidence of so-called primary lymphoma of this organ.

J Exp Med, 1979 Jul 1, 150(1), 1 - 9
The absence of H-2 antigens from mouse pancreatic beta-cells demonstrated by immunoferritin labeling; Parr EL; Islets of Langerhans were isolated from mouse pancreases and fixed in periodatelysine-paraformaldehyde . The fixed islets were then dissociated with trypsin and EDTA to yield cell suspensions that contained mainly four cell types; beta-cells, capillary endothelial cells, acinar cells, and pancreatic duct epithelial cells . The nonislet cells were probably associated wtih the surface of the isolated islets . The H-2 antigens of the dissociated pancreatic cells were labeled with an immunoferritin technique . Pancreatic duct epithelial cells showed specific ferritin labeling on their lateral cell membranes but not on apical microvillus membranes . Acinar cells were also labeled on lateral membranes, and the capillary endothelial cells were labeled on both the luminal and albuminal aspects of their surface membranes . In contrast, pancreatic beta-cells were unlabeled . The number of ferritin molecules per unit length of beta-cell membrane was essentially the same on cells from the antigenic strain and the congeneic control strain, and was about 200-fold less than on the labeled pancreatic duct epithelial cell lateral membranes . Pancreatic beta-cells are therefore one of six known epithelial cell types on which H-2 antigens can not be detected by immunoferritin labeling . The apparent absence of H-2 antigens from these cells suggests a study of the viability of beta-cells in allografts of dissociated islet cells, in which the beta-cell would not be in contact with antigenic cells . Such studies might lead to a new approach to the control of diabetes mellitus by transplantation.

J Biochem (Tokyo), 1979 Jul, 86(1), 225 - 30
Extrusion of sodium ions energized by respiration and glycolysis in Escherichia coli; Tsuchiya T et al.; Extrusion of sodium ion from cells of Escherichia coli was measured using an Na+ electrode . When oxygen was supplied to an anaerobic cell suspension, extrusion of Na+ was observed . The addition of glucose under anaerobic conditions also caused Na+ efflux . The extrusion of Na+ energized by respiration and glycolysis was completely inhibited by a proton conductor, carbonyl cyanide m-chlorophenylhydrazone . These observations are consistent with the view that Na+ transport occurs secondarily to H+ circulation . Interestgly, induction of the melibiose transport system, which is coupled to Na+, greatly enhanced Na+ transport activity.

Blood Cells, 1979 Jun 15, 5(2), 247 - 58
Mechanisms of haemopoietic stem cell proliferation control; Wright EG et al.; The control of stem cell (CFU-S) proliferation is mediated by short-range acting factors which can be detected by the proliferation modifying activities present in media conditioned by haemopoietic cells . A specific inhibitor of stem cell proliferation is obtained from haemopoietic tissue containing minimally proliferating CFU-S, whilst stimulatory material is obtained from cell suspensions containing rapidly proliferating CFU-S . Used competitively, these factors, which are detected in different molecular weight range fractions, manipulate the rate of CFU-S proliferation in a manner compatible with a physiological control mechanism . In addition, a long-term bone marrow culture system has been shown to provide an in vitro model of stem cell control . Fractionation of cell populations from haemopoietic tissues reveals marked concentration differences of the CFU-S proliferation modifying activities depending on the proliferative state of the CFU-S . However, irrespective of whether the tissue contains stem cells that are actively or minimally proliferating, both stimulatory and inhibitory activities are detected . From dose-response studies it is concluded that stem cell proliferation is controlled by an appropriate balance of stimulatory and inhibitory factors which, however, are not produced by the stem cells themselves.

Biochem J, 1979 Jun 15, 180(3), 685 - 8
Loss of cell constituents from hepatocytes on centrifugation; Sainsbury GM et al.; In studies of the metabolism of isolated hepatocytes, it is often necessary to measure the concentrations of cell constituents both in cells and medium . When hepatocytes are separated in the special tubes of Hems, Lund & Krebs (1975) (Biochem . J . 150, 47--50), they lose much glucose, urea and Na+, whereas there is no loss of K+, glutamate, aspartate and adenine nucleotides . Cell water is also lost, as measured by the distribution of 3H2O . This loss is mainly due to an exchange of cell water with the aqueous solution in the stems of the tubes through which the cells pass on centrifugation . In general, substances are lost only when the intracellular concentration is equal to, or lower than, the extracellular concentration . Probably solutes are lost because they travel with the water unidirectionally out of the cell . A loss of solute does not occur when the cells are centrifuged in conical tubes with a layer of silicone oil between the cell suspension and the deproteinizing layer . The reasons for the loss occurring in the special separation tubes are discussed.

Experientia, 1979 Jun 15, 35(6), 815 - 7
Density gradient centrifugation of cells separated from multicellular tumor spheroids; Sigdestad CP et al.; Cells from a murine fibrosarcome (FSa) have been grown in vitro as multicell tumor spheroids (MTS) . The growth rate of these MTS was determined . Following selected periods of growth, MTS were made into a single cell suspension and separated on linear density gradients of Renografin . While only 1 population of cells were separated from small spheriods (400 mum diameter), at least 3 subpopulations of tumor cells were separated and isolated from large spheroids (800 mum in diameter).

Aust J Biol Sci, 1979 Jun, 32(3), 299 - 307
Relationship between protein synthesis and secretion in liver cells and the state of the adenine nucleotide system; Edwards K et al.; Adenine nucleotide levels could be precisely and reproducibly adjusted in liver cell suspensions by partially depleting the ATP pool with D-fructose or glycerol . Thus, it was possible to quantitatively correlate rates of protein synthesis and secretion with intracellular levels of ATP and with derived parameters, such as the adenylate energy charge . Half the maximum rate of incorporation of leucine into protein was observed at an energy charge of 0.80, a ratio of ATP to ADP of 2.6, and an ATP level of 1.05 mumol per g of wet cells . Proteins were secreted with half the maximum rate at an energy charge of 0.85, a ratio of ATP to ADP of 3.1 and an ATP concentration of 1.1 mumol per g of wet cells . Protein secretion did not depend on continued synthesis . Inhibitors of oxidative phosphorylation inhibited protein secretion in addition to protein synthesis, in contrast to observations by other authors on liver slices.

Endocrinol Jpn, 1979 Jun, 26(3), 389 - 94
Effect of somatostatin on plasma renin activity; Izumi Y et al.; Intravenous infusion of somatostatin in mongrel dogs caused a significant decrease in the peripheral plasma renin activity (PRA) enhanced by pentobarbital sodium anesthesia or furosemide treatment . However, the inhibitory activity vanished within 10 min after termination of somatostatin infusion . Intrarenal arterial infusion of somatostatin decreased furosemide-enhanced PRA in renal vein by 24.0%, 16.6% and 8.6% in dose of 0.1, 0.5 and 1.0 microgram, respectively . On the other hand, high doses of the peptide (50-200 microgram) failed to decrease . The changes in PRA occurred in the absence of any alteration in blood pressure during the intravenous infusion under furosemide treatment . In an in vitro study, the addition of somatostatin in doses of 0.01 and 0.05 microgram suppressed the renin release in dog renal cortical cell suspension by 74.3% and 53.6%, respectively . Therefore, in both intrarenal arterial infusion and the cell suspension system, somatostatin was increasingly effective in decreasing renin release towards the lower end of the dose range tested . These results suggest that the effect of somatostatin on hyperreninemia may involve an inhibition of renin release at the cell level in the kidney.

Gut, 1979 Jun, 20(6), 484 - 8
Method of preparing isolated colonic epithelial cells (colonocytes) for metabolic studies; Roediger WE et al.; Suspensions of isolated colonic epithelial cells (colonocytes) have been obtained from rats by incubating everted lengths of colon with EDTA at 37 degrees C in Krebs-Henseleit saline from which calcium was omitted and containing 0.25% (w/v) bovine serum albumin . Measurements of oxygen consumption and lactate production by cell suspensions indicate that they are metabolically active for at least one hour . The method has been modified for the preparation of isolated epithelial cells from the human colon by including an enzyme digestion step and by increasing the concentration of EDTA to 10 mM . Human colonocytes have been obtained either from normal mucosa (ascending and descending colon) or from the mucosa in ulcerative colitis (descending colon) . Oxygen consumption of human cell suspensions is lower than in the rat but in colonocytes from both species the rate is increased by glucose and by n-butyrate, a normal constituent of the colonic lumen . The method yields metabolically active cell suspensions from diseased colonic mucosa and promises to be of value for biochemical studies of ulcerative colitis.

J Exp Med, 1979 Jun 1, 149(6), 1504 - 18
Origin, Kinetics, and characteristics of pulmonary macrophages in the normal steady state; van oud Alblas AB et al.; Pulmonary macrophages of mice in the steady state were isolated by lavage with PBS containing EDTA and subsequent enzymatic digestion of tissue with pronase and DNA-ase . By this method, the total pulmonary macrophage population was obtained in two cell suspensions, one with a pure population of pulmonary alveolar macrophages (PAM) and the other with a mixed population of pulmonary alveolar and pulmonary tissue macrophages (PTM) . The morphological, cytochemical, and functional characteristics of both PAM and PTM were like those of mature tissue macrophages except for the presence of C3 receptors . These receptors were almost absent on PAM and present on a larger number of cells in the mixed population of PAM and PTM . The total pulmonary macrophage population of mice in the steady state is approximately equal to 2 x 10(6), of which about 93% are PAM and about 7% are PTM . In labeling experiments with 3H-thymidine, the low in vitro labeling indices (less than 3%) for both PAM and the mixture of PAM and PTM, showed that both are essentially nondividing cells . In vivo labeling studies showed an increase in the number of labeled macrophages that can only be attributed to labeled monocytes migrating into the lungs . Additional evidence was provided by a decrease in the labeling indices of pulmonary macrophages when mice were treated with hydrocortisone acetate, which causes a severe monocytopenia, thus preventing monocyte influx into the lungs . Confirmation of the bone marrow origin was obtained in mice labeled after x-irradiation with partial bone marrow shielding: labeled pulmonary macrophages were found in the exposed lungs . In all experiments, the labeling indices were identical in the two macrophage populations isolated . These results show that the influx of monocytes is the source of cell renewal for the pulmonary macrophages . No indications for an interstitial division or maturation compartment in the lung were found . Quantitation of the efflux of labeled monocytes from the blood, and the number of labeled pulmonary macrophages, showed that in the steady state about 15% of the monocytes leaving the circulation become pulmonary macrophages and that the turnover time of pulmonary macrophages is approximately equal to 27 d.

Zentralbl Bakteriol {Orig A}, 1979 Jun, 244(1), 17 - 24
Comparative evaluation of immunofluorescent (IgM and IgG) and complement-fixing antibodies in influenza A infection; Masihi KN et al.; The indirect immunofluorescent (FA) tests for detection of IgG and IgM antibodies to the internal antigens of influenza viruses were performed using single cell suspensions of baby hamster kidney cells . The IgG-FA test showed a good correlation with the complement fixation (CF) test performed with purified ribonucleoprotein (RNP) as antigen than the CF test with whole virus antigen . Sera which were positive only in the IgM-FA test did not react in the RNP-CF test . A rapid diagnosis of influenza was not possible alone by detection of RNP specific IgM as relatively low titers were obtained in the IgM-FA test.

Biull Eksp Biol Med, 1979 Jun, 87(6), 625 - 7
{Method of culturing amniotic fluid cells}; Vorsanova SG; The influence of pregnancy term and the concentration of cell suspension, introduced into culture, on the growth of amniotic fluid cells have been studied on 29 specimens . Optimum term of amniotic fluid cells sampling for the best growth was 17 weeks of pregnancy . It is recommended to take into account the concentration of cell suspension in the amniotic fluid before introducing the cells into the culture depending on pregnancy terms.

Am J Clin Pathol, 1979 Jun, 71(6), 651 - 64
Correlations of immunologic markers with histologic features of human non-Hodgkin's lymphomas; Brubaker DB et al.; Twenty-five lymph nodes from patients with non-Hodgkin's lymohomas were evaluated by immunologic technics applied to cell suspensions and tissue sections . Malignant lymphomas with cytologic characteristics similar to those of neoplastic cells were found to be immunologically heterogeneous . The distribution as well as the number of neoplastic cells with distinctive immunologic surface markers could not be related to the cytologic type of malignant lymphomas . The number of malignant cells simultaneously expressing the T- and B-cell markers was increased in malignant lymphoma nodes . Cells positive for the triple markers (Ig+, EAC+, T+, where Ig = immunoglobulin, EAC = erythrocytes sensitized with antibody and complement, and T = T marker) represented the predominant population in these nodes, and the distributions of these cells were useful in diagnosis . Monoclonal immunoglobulins were detected in all lymphoma cells but not in the patients' sera . The tissue distribution of EAC-positive cells may have a prognostic significance . The paucity of cells with the Fc receptors was a characteristic feature of all lymphoma cells studied . Evaluations of immunologic markers on lymphoma cells in conjunction with the histologic characteristics may provide a sounder basis for diagnosis.

Clin Exp Immunol, 1979 Jun, 36(3), 502 - 10
Study of some properties of the receptor for IgM on human lymphocytes; Romagnani S et al.; Some properties of the receptor for IgM on human lymphocytes have been investigated . It was shown that the interaction of native IgM with the receptor present on T and B lymphocytes is not critical for its detection in the EAM-rosette assay . In fact, high values of EAM-RFC could be found on cell suspensions cultured overnight in either IgM-free or IgM-containing media . In addition, the inhibition of EAM-rosettes by human monoclonal IgM at 37 degrees C was not as effective as at 4 degrees C . Rabbit IgM showed a significantly greater ability to inhibit the binding of antigen-IgM antibody complexes than human IgM . The receptor for IgM was easily removed by handling procedures, the incubation of lymphocytes at 4 degrees C and treatment of the cells with low concentrations of trypsin or pronase . After the enzymatic treatment, a rapid resynthesis occurred, which restored the number of EAM-rosettes formed by T cells and significantly increased the number formed by B cells . The interaction between the receptor and antigen-IgM antibody complexes stopped the spontaneous shedding of the receptor at 4 degrees C . When the incubation of the cells with immune complexes was performed at 37 degrees C, a significantly different behaviour between T cells equipped with receptor for IgM and those possessing receptor for IgG was found . After the binding of EAG to the receptor for IgG, a process of rapid dissociation of rosettes occurred, whereas the incubation with EAM did not induce an irreversible loss of the receptor for IgM.

J Natl Cancer Inst, 1979 Jun, 62(6), 1497 - 502
Inhibition of in vitro Friend murine leukemia virus infection of lipopolysaccharide-activated B-cells with concanavalin A; Bowen DL et al.; Stimulation with bacterial lipopolysaccharide (LPS) of splenic B-lymphocytes infected in vitro with Friend virus complex increased the number of cells with replicating murine leukemia virus (MuLV) {i.e., infectious centers (IC)} up to 100-fold . Concanavalin A (Con A) did not have such an effect . However, the addition of Con A to the LPS-stimulated cultures decreased the number of IC . The inhibitory concentration of Con A (2.5 microgram/ml) was eightfold less than that capable of neutralizing the in vitro infectivity of MuLV (20 microgram/ml) . The effect of Con A was not mediated by T-cells; the inhibition of infection was comparable with use of whole spleen cell suspensions from normal BALB/c mice, with T-cell-depleted cell suspensions, or with spleen cells with congenitally athymic nude mice . However, specific removal of Con A from the surface of B-cells with alpha-methyl-D-mannopyranoside prior to the infection reversed the inhibitory effect entirely . It is suggested that the lectin interferes with MuLV on the membrane of B-cells.

Immunopharmacology, 1979 Jun, 1(3), 187 - 201
The role of macrophages in stimulation of immune induction and myelopoiesis: II: analysis of genetic restriction involved in the stimulation of granulocyte colony precursors or mature lymphocytes using factors prepared from different recombinant inbred strains of mice; Gorczynski RM et al.; The genetic restriction involved in the reconstitution of immune responses in macrophage-depleted mouse spleen cultures, or the induction of colony formation in bone marrow cultures, by different molecular-weight species of lymphostimulatory molecules derived from mouse peritoneal cell suspensions is reported . The data suggest little evidence for genetic restriction in the ability of any of the factors to stimulate bone marrow colony formation in vitro . However, when immunological stimulation was investigated, a restriction coded for by genes in the K/D end of the MHC (70-90K factor) or in the I region of the MHC (30-45K factor) was observed . A third species of lymphostimulatory molecule (15K) showed no such restriction . Further evidence is presented to suggest that the active moiety in the 70-90K molecule(s) is a 15K-like species (nonrestricted in its ability to reconstitute cells from different strains of mice.

Am J Anat, 1979 Jun, 155(2), 281 - 6
The isolation of single cells from the avian salt gland; Thompson IG; Collagenase, hyaluronidase, and trypsin were used to isolate single cells from the avian salt gland . Three cell types were distinquishable in the resultant cell suspension: peripheral, intermediate, and principal cells . The fine structure of these cells is described and related to the morphology of the intact gland.

Immunology, 1979 Jun, 37(2), 377 - 84
Receptors for activated C3 on thymus-dependent (T) lymphocytes of normal guinea-pigs; Wilson AB et al.; In a survey of lymphocyte subpopulations in normal guinea-pig blood, lymph node, spleen, thymus and peritoneal cavity, a considerable overlap was observed between the percentages of C3-receptor bearing lymphocytes (CRL) and of thymus-dependent (T) cells in lymph nodes . Simultaneous rosette-formation reactions with sheep erythrocytes carrying rabbit complement (EAC) and papain-treated rabbit erythrocytes (a T-cell marker) revealed that 20--50% of the lymph node CRL were T lymphocytes . These experiments and others on cell suspensions depleted of Ig-bearing (B) lymphocytes showed that between 8 and 36% of lymph node T cells have complement receptors . The frequency of T-CRL in other lymphoid tissues was lower, representing between 0 and 8% of the T-cell population . The reaction of T-CRL and EAC was not inhibited by EDTA which is known to inhibit the C3 receptor activity on macrophages.

Br J Haematol, 1979 Jun, 42(2), 303 - 14
ADCC (K-cell)lysis of human erythrocytes sensitized with rhesus alloantibodies . I . Investigation of in vitro culture variables; Urbaniak SJ; An ADCC system has been developed using anti-D and papainized group O rhesus (D) positive red cells as the targets . Monocyte depleted mononuclear cell suspensions were effective in lysing appropriately sensitized red cells and papainization considerably enhanced the degree of specific lysis . Variation in culture volume and incubation in tubes or microplates were not critical to the degree of specific lysis obtained provided that the number of effector cells and target cells per culture was constant and the anti-D not diluted below the optimal concentration . Cytolytic activity was seen down to levels of 3 ng anti-D per culture . Specificity for lysis resided with the anti-D and not the effector cells . Several sources of anti-D were effective in inducing lysis of D positive red cells although individual variation was noted . Anti-c and anti-E were also shown to be effective in inducing specific lysis of red cells with the appropriate antigens.

Immunology, 1979 Jun, 37(2), 353 - 9
Studies on the resistance to tolerance induction against human IgG in DDD mice . II . Tolerogen-resistant T-cell population in the spleen; Hosono M et al.; Further studies were carried out to investigate cellular sites of the resistance to the induction of immunological tolerance to HGG in DDD mice, assuming the presence of a subset of tolerogen-resistant splenic T cells . Spleen-seeking T cells were shown to be relatively resistant in comparison with lymph node-seeking T cells . The existence of a tolerogen-resistant T-cell subpopulation was indicated from the experiments demonstrating that tolerance was easily attained after adult thymectomy and that lymph node T cells became much more resistant to tolerance induction after adult splenectomy . The latter experimental result might also exclude the possibility of differences in microenvironment (probably in A cells) between spleen and lymph node . An attempt was made to investigate a possible involvement of A cells in the induction of tolerance . A cells were deprived in vivo by irradiation of the host 3 days prior to spleen cell transfer and in vitro by passing a spleen cell suspension through a Sephadox G-10 column . The deprivation of A cells resulted in priming of the host by the tolerogen rather than easier tolerance induction . No suppressive activity was observed in lymph node cells from tolerized mice . These results suggest that there exists a set of T cells, generated relatively recently in the thymus, preferentially migrating into spleen and there becoming resistant to tolerance induction.

Int J Cancer, 1979 May 15, 23(5), 626 - 31
Isolation and characterization of lymphocytes and macrophages from solid, malignant human tumours; Svennevig JL et al.; In mechanically prepared cell suspensions from 17 solid, malignant human tumours, 0.5-5.0% (mean 2.0%) lymphocytes and 1.0-28.0% (mean 7.4+) macrophages were found . Mononuclear cells (MC) were isolated using the Boyum technique . From each biopsy weghing 1-4 g, on average, 1.3 x 10(6) lymphocytes and 0.8 x 10(6) macrophages were recovered . The tumour-infiltrating lymphocytes (TIL) were characterized with regard to T and B markers . The proportion of TIL-forming rosettes with SRBC (T cells) was 43%, which was significantly less than for peripheral blood lymphocytes (PBL) from cancer patients (58%), or normal controls (80%), On average, 15% of the TIL were B cells, whereas 42% had no T- or B-cell markers . Macrophages (TIM) were identified by non-specific esterase staining and phagocytosis . In four cases the tumour cells were also stained with alpha-naphthyl butyrate . Corresponding findings were made on esterase-stained cryostat sections from four tumours . Macrophages were found within and around the tumour tissues, occasionally localized to necrotic areas, but in most cases with no sign of necrosis of the surrounding cells . In some tumour cell suspensions typical clusters of lymphocytes and macrophages were seen . Total lymphocytes and T-cell were markedly reduced inthe peripheral blood of cancer patients, whereas total monocyte counts were within the normal range.

Br J Cancer, 1979 May, 39(5), 570 - 7
An approach to the problem of heterogeneity of human tumour-cell populations; Sirachy J; 1 . Successive sampling of ovarian cancers during cytostatic treatment showed several cases of notable changes in their ploidy distribution and one change in model chromosome number, indicating selection of a resistant tumour-cell population . 2 . Studies of cell suspensions from human tumour specimens incubated with {3H}-TdR after exposure in vitro to various cytostatic agents have shown variation in labelling between different parts of the same tumour, as well as between the primary tumour and its metastases or ascitic tumour-cell population, which may be accounted for by variation in sensitivity of the tumour-cell population . 3 . Studies of nuclear morphology in 20 endometrial cancers before and after progesterone therapy demonstrate considerable variation in the proportion of cells undergoing secretory conversion within the same tumour, indicating primary heterogeneity of the tumour-cell population in response to progesterone.

In Vitro, 1979 May, 15(5), 315 - 25
A microtechnique for the rapid analysis of macromolecule synthesis in minicultures of mammalian cells; Fusenig NE et al.; A new micromethod, called the Stanzen technique, is described for the rapid determination of DNA and protein content as well as the incorporation rates of radioactively labeled precursors into macromolecules in cells growing in replica minicultures on plastic petri dishes . The procedure yielded reproducible results assaying only minimal cell numbers per sample and was applied for studying both primary or early passaged cell cultures (mouse epidermal cells and fibroblasts) and a malignantly transformed epidermal cell line . In four well defined circular areas (called Stanzen) marked on the bottom of tissue-culture plastic petri dishes (by heated stamps), 0.2 to 4 x 10(5) cells per area were plated and grown as four individual cultures in one dish . Both treatment and labeling with radioactive precursors of these Stanzen cultures were performed as with normal petri dishes . After fixation and extraction of the cultures, the singular Stanzen areas (with the cells fixed onto them) were sawed out and transferred into vials for liquid-scintillation counting or determination of DNA and protein . The obtained values of specific activity corresponded well whether the samples compared were derived from the minicultures of the same dish or from several dishes . By modifications of the known colorimetric methods for DNA and protein determination, the sensitivity of these procedures was improved down to values of 1 microgram DNA or 5 micrograms protein per individual culture . These micromodifications yielded the same values as the standard methods whether applied to cell suspensions or to cell cultures . Finally, cell proliferation was not influenced by the growth conditions in the small Stanzen areas and proceeded as in normal dishes or larger areas similarly stamped on the bottom of petri dishes . Since this method proved valuable for biochemical studies using primary cultures of mouse epidermal cells (saving cell material by a factor of 10, test substances and time), it might also be advantageous for other purposes as well where the availability of cells or test substances are limiting factors for large test series.

Cell Tissue Kinet, 1979 May, 12(3), 319 - 37
Circadian rhythms in mouse epidermal basal cell proliferation . Variations in compartment size, flux and phase duration; Clausen OP et al.; Several kinetic parameters of basal cell proliferation in hairless mouse epidermis were studied, and all parameters clearly showed circadian fluctuations during two successive 24 hr periods . Mitotic indices and the mitotic rate were studied in histological sections; the proportions of cells with S and G2 phase DNA content were measured by flow cytometry of isolated basal cells, and the {3H}TdR labelling indices and grain densities were determined by autoradiography in smears from basal cell suspensions . The influx and efflux of cells from each cell cycle phase were calculated from sinusoidal curves adapted to the cell kinetic findings and the phase durations were determined . A peak of cells in S phase was observed around midnight, and a cohort of partially synchronized cells passed from the S phase to the G2 phase and traversed the G2 phase and mitosis in the early morning . The fluctuations in the influx of cells into the S phase were small compared with the variations in efflux from the S phase and the flux through the subsequent cell cycle phases . The resulting delay in cell cycle traverse through S phase before midnight could well account for the accumulation of cells in S phase and, therefore, also the subsequent partial synchrony of cell cycle traverse through the G2 phase and mitosis . Circadian variations in the duration of the S phase, the G2 phase and mitosis were clearly demonstrated.

J Immunol, 1979 May, 122(5), 2026 - 31
Humoral and formed elements of blood modulate the response of peripheral blood monocytes . I . Plasma and serum inhibit and platelets enhance monocyte adherence; Musson RA et al.; Human and rabbit peripheral blood monocytes normally adhere to plastic tissue culture plates in vitro when they are suspended in Hanks' media . Increasing amounts of autologous serum or heat-inactivated plasma in the cell suspensions prevented the adherence of both monocytes and lymphocytes . The inhibitory effect of plasma was separated into three areas of activity by chromatography on Sephacryl S-200 . The profile of inhibitory activity did not coincide with the protein elution profile, suggesting that inhibition was not a nonspecific protein effect . A layer of adherent platelets overcame the inhibitory effect of plasma on monocyte adherence . Platelets selectively increased monocyte as opposed to lymphocyte adherence and this was specific for platelets in that neither neutrophils nor fibroblasts could substitute for platelets . Both plasma and platelets acted directly on monocytes.

Cell Biol Int Rep, 1979 May, 3(3), 257 - 63
Quantitative assessment of the amount and the activity of trypsin associated with trypsinized cells; Brugmans M et al.; The present investigation has demonstrated that when cell layers are trypsinized with 125I-trypsin and washed under strictly standardized conditions, the amount of trypsin which remains associated with the cell suspension can be accurately determined . This amount is more than 10 times greater than would be expected from dilution only and is dependent on the density of the cell layers . On plating of the cells, less than 10% of the carry-over trypsin remains associated with the cells and suggestive evidence for a mainly intracellular localization was obtained with a quantitative immunoperoxidase technique . This carry-over trypsin was further shown to maintain proteolytic activity by its ability to remove significant amounts of macromolecular material from a cell layer prelabeled with 3H-Leucine.

Cancer Res, 1979 Apr, 39(4), 1347 - 52
Egg lectin of Rana japonica and its receptor glycoprotein of Ehrlich tumor cells; Sakakibara F et al.; Egg lectin of Rana japonica, which specifically agglutinates transformed cells but does not agglutinate nontransformed cells and erythrocytes, has been isolated by gel filtration and successive ion-exchange chromatographies on diethylaminoethyl cellulose and carboxymethylcellulose columns and has been characterized as a homogeneous carbohydrate-free protein with a relative molecular weight of 13,500 . The lectin, at a concentration of 1 microgram/0.1 ml, causes obvious cytoagglutination of various transformed and tumor cell . The receptor of the Erlich ascites tumor cells which inhibits the lectin-induced agglutination of the Ehrlich ascites tumor cells has been isolated and characterized . The receptor was solubilized from Ehrlich ascites carcinoma cells by treating a tumor cell suspension with insolubilized trypsin, and the solubilized receptor was isolated by gel filtration through Sephadex G-100, followed by ion-exchange chromatography on diethylaminoethyl cellulose . The receptor was identified as a homogeneous glycoprotein having about 25% carbohydrate . The receptor, at a concentration of 4 microgram/0.1 ml, completely inhibited the cytoagglutination of the Ehrlich carcinoma cells caused by three agglutination doses (about 3 microgram/0.1 ml) of the R . japonica lectin.

Exp Hematol, 1979 Apr, 7(4), 171 - 6
Quantitative development of adherent cell colonies in bone marrow cell culture in vitro; Mori KJ et al.; Quantification of the formation of adherent cell colonies in bone marrow cell culture was attempted . By secondary transfer of the bone marrow cells as a single cell suspension after 4 days' culture of fine marrow fragments, a linear relationship was obtained between the number of adherent cell colonies developing and the number of cells secondarily inoculated into the culture bottle . This suggests that 4 days' culture of the bone marrow cells with close intercellular interactions is sufficient for the 'conditioning' of the cells to develop adherent cell colonies . Activity of such colonies to support haemopoietic stem cell proliferation was also shown.

Eur J Immunol, 1979 Apr, 9(4), 272 - 5
The distribution of HLA on human lymphoid, bone marrow and peripheral blood cells; Brown G et al.; The cellular distribution and the differential expression of HLA on cell suspensions and tissue sections has been investigated using the monoclonal antibody W6-32, which reacts with the high molecular weight chain of the major histocompatibility antigen . Lymphocytes and platelets, as assessed by autoradiographic and immunoperoxidase labeling, were the most densely labeled cells . Myeloid precursors showed more labeling than mature neutrophils . Electron microscopic immunoperoxidase labeling showed a continuous distribution of HLA antigen on lymphoid and myeloid cell membranes . Erythroid precursors (including reticulocytes), although very weakly labeled, were clearly positive, in comparison with mature erythrocytes . In the thymus, HLA-negative, thymocyte antigen-positive cells (85%) can be distinguished from HLA-positive, thymocyte antigen-negative cells (15%) . By using immunofluorescence techniques on tissue sections, the former cells were shown to be cortical thymocytes and the latter medullary cells.

Ann Rheum Dis, 1979 Apr, 38(2), 166 - 70
Synthesis of sulphated proteoglycans by rheumatoid and normal synovial tissue in culture; Marsh JM et al.; Synthesis of sulphated proteoglycans by cell lines derived from explants of 7 rheumatoid and 9 normal specimens of synovial tissue, as well as by 7 lines of skin fibroblasts from non-rheumatoid patients, was examined . Cells of all 3 types were cultured as monolayers . They were then disaggregated and their capacity to synthesise proteoglycan estimated in cell suspensions by the incorporation of {35S}-sulphate into CPC-precipitable material during 2 hours of incubation . Cell suspensions incorporated somewhat more {35S}-sulphate than corresponding duplicate monolayers . Synovial cells from rheumatoid patients incorporated 2 to 3 times as much {35S}-sulphate as synovial cells from normals . Skin fibroblasts, however, incorporated less {35S}-sulphate than rheumatoid or normal synovial cells up to the fifth passage . Thereafter their incorporation gradually increased to overtake that of synovial cells . About one-half to one-third of the total {35S}-sulphate labelled material was closely associated with cells from synovial tissues and fibroblasts respectively.

Endocrinology, 1979 Apr, 104(4), 1152 - 7
Glucocorticoid receptors in thymocytes of fetus, newborn, and adult CBA mice; Duval D et al.; {3H}Dexamethasone binding was studied in vitro in cell suspensions of thymus from fetal and newborn mice . The number of glucocorticoid receptors appeared to be identical in fetal, newborn, and adult CBA mice . The affinities of these receptors, calculated by Scatchard analysis, were similar in the three groups of animals . The extent of in vitro steroid-induced inhibition of {3H}uridine incorporation by fetal and adult thymocyte suspensions was very similar . These results suggest that no significant variations in glucocorticoid receptors occur in thymic tissue during the neonatal period.

Cancer Res, 1979 Apr, 39(4), 1305 - 9
Tumor angiogenesis activity in clonal cells transformed by bovine adenovirus type 3; Tsukamoto K et al.; Four different sets of clonal cells transformed by bovine adenovirus type 3 and its oncogenic DNA fragments, and their clonal normal counterparts, were tested for tumor angiogenesis activity . The activity was assayed by measuring the host-mediated vascular response of a chorioallantoic membrane to the cell suspension separated from the vascular bed by a Millipore filter . Angiogenesis activity due to inflammation reaction was prevented by using corticosteroids . All of the transformed cells tested induced strong vascular responses as compared with their corresponding clonal normal cells . Cell dose and time dependency for the expression of the activity were also shown.

Cancer, 1979 Apr, 43(4), 1216 - 24
Predictability of immunologic phenotype of malignant lymphomas by conventional morphology: a study of 60 cases; Frizzera G et al.; In order to test the immunologic validity of the Lukes-Collins (L-C) classification of the non-Hodgkin's lymphomas (ML), 60 ML in adult patients were studied and their B- or T-cell nature was predicted on a morphologic basis, without knowledge of the clinical history or the results of surface marker (SM) studies (SIg, C', Fc and E-rosettes), which were performed on cell suspensions and cryostat sections from the same specimens used for histology . There was a good correlation between morphologic types and SM (97% for the nodular ML, 81% for the diffuse) . The predictions were not confirmed in 6 instances: one nodular ML typed as T; one convoluted lymphocytic ML typed as histiocytic; and four diffuse ML, predicted to be of B-type, bore no detectable SM ("Null" ML) . It is concluded that the L-C morphologic criteria do allow in most cases the recognition of the B- or T-cell nature of ML, but cannot detect variations of the SM pattern which seem to affect the clinical behavior of these neoplasias . Thus, while the L-C classification seems immunologically sound, its clinical relevance still needs to be demonstrated.

Cancer, 1979 Apr, 43(4), 1165 - 76
Differentiation between benign and malignant human lymph nodes by means of immunologic markers; Brubaker DB et al.; A surface-marker assay combining immunofluorescence with anti-human immunoglobulin or anti-human brain serum (AHBS) and the formation of rosettes with untreated (E), antibody-sensitized (EA) and complement-coated (EAC) sheep erythrocytes was used to study mononuclear cell suspensions of human lymph nodes . The frequency of cells expressing more than one marker was increased in lymphoma nodes as compared to normal and hyperplastic nodes . The cells which simultaneously expressed complement receptors, surface immunoglobulin and the marker identified by AHBS represented the most prominent and characteristic subpopulation identified in neoplastic nodes . Distributions of cells with double and triple markers were studied by combining immunofluorescence with rosetting on frozen tissue sections . The multiple-marker cells had distributions that were characteristic in different human lymphomas . Benign and malignant human nodes could be distinguished on the basis of frequency and distribution of mononuclear cell populations carrying distinctive combinations of T- and B-cell surface markers.

Cancer Treat Rep, 1979 Apr, 63(4), 571 - 4
Blood and lymph node T lymphocytes in cutaneous T cell lymphoma: evaluation by light microscopy; Schechter GP et al.; Cytology of peripheral blood and lymph node lymphocytes from a group of unselected patients with cutaneous T cell lymphoma (CTCL) was studied by light microscopy . Twenty of 45 patients had circulating lymphocytes with convoluted nuclei recognized in routine Wright-Giemsa-stained peripheral blood smears . Cytocentrifuge preparations of E-rosetted lymphocytes showed that greater than 10% of the T cells had convoluted nuclei in each of 16 patients with positive blood smears and in six of 17 whose blood smears were negative or inconclusive . Peripheral blood involvement with greater than 10% convoluted T cells was most frequent in patients with erythroderma (100%) including those with normal of decreased lymphocyte counts, and was not uncommon in patients with mycosis fungoides in the plaque or tumor phase (42%) . The light-microscopic morphology of the abnormal cells found in the patients with the plaque or tumor phase of mycosis fungoides was not distinguishable from that of the erythrodermic patients . Increased percentages (less than 15%) of T cells having convoluted nuclei were also found in the lymph node cell suspensions from CTCL patients with adenopathy (18 of 25 patients) . These results suggest that a high frequency of extracutaneous involvement occurs in patient with CTCL, the clinical significance of which remains to be determined.

Steroids, 1979 Apr, 33(4), 435 - 58
An improved procedure for the preparation of rat uterine cell suspensions; Muller RE et al.; In the present paper we report on an improved procedure for the preparation of free uterine cells which avoids the use of trypsin and employs very low concentration of collagenase . The cells released mechanically from the digested tissue are constantly removed from the enzyme containing medium, thus minimizing exposure to collagenase . 60%-70% of the cells which make up the intact uterus are obtained as free cells and 95% of these cells are viable for at least 15 hours at 37 degrees . Metabolic integrity was assessed by measuring the cell's ability to oxidize glucose and synthesize proteins over extended periods of time . The membrane leucine carrier protein and the membrane Na+/K+ ATPase were found to be fully functional . Electron microscopic analysis of the cells confirmed their structural integrity . Data are presented illustrating that with this system the estrogen binding protein is stable at physiological temperatures . The cells contain approximately 30,000 specific estrogen binding sites, with an apparent KA of 5--6 x 10(9) M-1 . At 37 degrees 80% of the hormone receptor complexes were in the nuclear fraction, 20% in the cytoplasm . The similarity of the estrogen receptor binding parameters with those measured in the intact tissue after in vivo hormone adminsistration, together with the cells' structural and metabolic integrity make this procedure for the preparation of uterine cell suspensions in high yields particularly suitable for studies in which minimal cell injury is an essential prerequisite.

Br J Pharmacol, 1979 Apr, 65(4), 671 - 6
The effects of opioid drugs and of lithium on steroidogenesis in rat adrenal cell suspensions; Gibson A et al.; 1 . The effects of opioid drugs and of Na+ replacement on steroidogenesis in rat adrenal cell suspensions were investigated . 2 . In medium containing normal Na+ (156 mM), opioid antagonists but not opioid agonists reduced the steroidogenic response to adrenocorticotrophic hormone1-24 (ACTH1-24) but not to dibutyryl adenosine 3',5' cyclic monophosphate (db cyclic AMP) . 3 . Replacement of 50% Na+ in the medium by choline had no effect on steroidogenesis, but further reductions in Na+ content reduced the steroidogenic activity of both ACTH1-24 and db cyclic AMP . 4 . In 50% Na+ medium both opioid agonists and antagonists inhibited ACTH1-24 induced steroidogenesis . 5 . Addition of therapeutic concentrations of lithium to otherwise normal medium inhibited the steroidogenic response to ACTH1--24 but not to db cyclic AMP . 6 . The selective inhibition of ACTH1--24-induced steroidogenesis by opioid drugs suggests some similarity between the opioid and ACTH receptors . 7 . The relevance of the potent inhibitory effect of lithium to its therapeutic actions is discussed.

Zh Mikrobiol Epidemiol Immunobiol, 1979 Apr, (4), 50 - 6
{Design of stable immunoglobulin erythrocyte diagnostica . 1 . Erythocyte fixation and their sensitization by specific immunoglobulins}; Barban PS et al.; The work presents the results of developing the method of fixation of erythrocyte constituting the cellular base of immunoglobulin erythrocytic diagnostic preparations and the sensitization of erythrocytes with immunoglobulin preparations of various specificity . Based on Ingraham's method, modified method of erythrocyte stabilization has been developed; it consists in the treatment of 50% cell suspension with 4% formaldehyde solution in the presence of 0.5% sucrose (erythrocyte suspension and formaldehyde solution being in the ratio 1 : 2.5) . An economic and highly productive technique of sensitizing erythrocytes with immunoglobulin preparations has been developed . The essence of this technique lies in the interaction between 6% suspension of erythrocytes treated with formalin and tannin and the equal volume of sensitin taken in a working dose . The work also presents the method of synthesizing the bifunctional compound fluoro-borate bis-daizonium complex (obtained from benzidine) and discusses the comparative possibilities of the methods of developing immunoglobulin erythrocytic diagnostic preparations by sensitization of tannin-treated erythrocytes and by chemical conjugation.

J Membr Biol, 1979 Mar 28, 45(1-2), 61 - 79
Interaction of tritium-labeled H2DIDS (4,4'-diisothiocyano-1,2,diphenyl ethane-2,2'disulfonic acid) with the Ehrlich mouse ascites tumor cell; Levinson C et al.; The experiments reported in this paper were undertaken to explore the interaction of tritiated H2DIDS (4,4'-diisothiocyano-1,2,diphenyl ethane-2,2'-disulfonic acid) with Ehrlich ascites tumor cells . Addition of (3H)H2DIDS to tumor cell suspension at 21 degrees C, pH 7.3, resulted in: (i) rapid reversible binding which increased with time and (ii) inhibition of sulfate transport . Tightly bound H2DIDS i.e., reagent not removed by cell washing, also increased with time . Binding of 0.02 nmol H2DIDS/mg dry mass or less did not affect sulfate transport, but, at greater than 0.02 nmol and up to 0.15 nmol the relationship between tight binding and inhibition of transport is linear . The fact that H2DIDS could bind to the cell and yet not affect anion transport suggests that binding sites exist unrelated to those concerned with the regulation of anion permeability . Support for this is the observation that H2DIDS is spontaneously released from cells even after extensive washings by a temperature-sensitive process . The most important source of released H2DIDS is the cell surface coat which labels rapidly (within 1 min) and is then spontaneously released into the medium . A second source is derived from H2DIDS that slowly entered the cells . Consequently, at least four modes of interaction exist between H2DIDS and ascites tumor cells . These include both reversible and irreversible binding to membrane components which regulate anion permeability, irreversible binding to cell surface proteins or glycocalyx, and finally incorporation of H2DIDS into the intracellular phase.

J Rheumatol, 1979 Mar-Apr, 6(2), 124 - 30
Use of enzymatically isolated chondrocytes for short term metabolic studies; Mitrovic D et al.; Chondrocytes isolated from calf articular cartilage by pretreatment with various enzymes prior to collagenase digestion were examined to determine the effect of enzymatic exposure on cell viability and to establish optimal conditions whereby freshly isolated cells could be used for short term metabolic studies . Pre-collagenase exposure to proteolytic enzymes for short intervals has no effect on cell viability . Trypsin pre-treatment appeared to increase the efficiency of cell isolation . Proteoglycan and RNA synthetic activity was influenced by the conditions of incubation (i.e., cell suspension vs . cell pellet: with or without a 24 hour "rest" period; and differential pre-collagenase enzyme exposure) . The data suggest that the experimental conditions of incubation and the enzymes used in isolation of the cells, materially alter the freshly isolated chondrocyte's "pattern" of metabolic activity in short term culture studies.

Rev Can Biol, 1979 Mar, 38(1), 17 - 25
{Relationship between anatomical structure and metabolism of plant tissues . I . Differences between the qualitative and quantitative composition of phenolic substances of apple explants and that of callus and cells produced by the culture}; Phan CT et al.; Relationship between anatomical structure and metabolism of plant tissues . I . Differences between the qualitative and quantitative composition of phenolic substances of apple-fruit explants and that of calli and cells cultured from these explants . Phenolic compounds of intact apple-fruits (CV . Golden delicious), fruit fragments cultured on agar medium, newly formed calli and cell suspensions prepared from these calli, were studied quantitatively and qualitatively . The phenol content of the tissues decreased during the first days of culture, then recovered practically the initial level just before the initiating calli became visible . This content is very low in the calli and in the cultured cells . But the most remarkable result is that the qualitative compositions of the phenols extracted from the fruit tissues, the calli and the cells were different : p-coumaryglucose, which is abundant in the fruit, disappeared almost completely in the calli, in which three compounds were formed de novo, X1 which was tentatively identified as ferulylquinic acid, X2, a glycoside of p-coumaric acid different from p-coumarylglucose, and X3 not yet identified; the cells synthesized also X1 and X3 but not X2, and contained no p-coumaryglucose while feruylquinic acid was abundant . The study on the processes of induction or regulation of the enzymes implied in these metabolic modifications is under way.

Mikrobiologiia, 1979 Mar-Apr, 48(2), 286 - 95
{Change in the structural organization of the respiratory apparatus of Mycobacterium rubrum depending on the cultivation conditions}; Poglazova MN et al.; Changes in the respiration apparatus of Mycobacterium rubrum were studied in the lag phase . The number of mitochondrial analogues was found to increase in parallel with the cellular growth, reaching a certain density of distribution per unit surface of the cells . The analogues of mitochondria were very labile . They rearranged easily, depending on the conditions of bacterial cultivation, but were always present in the cells as a discrete structure . The cellular growth and an increase of the mitochondrial analogues in them at 24 and 37 degrees C ceased by the 6-8th hr, regardless of the presence of glucose in the medium . Transition of the culture to the log phase at 24 degrees C was delayed to 16-18 hrs . After division, cells cultivated in media containing glucose were much larger than those grown in media without glucose, and the density of distribution in them of the mitochondrial analogues was higher . A decrease of temperature had no effect on the bacterial growth, but inhibited their division . The rate of oxygen uptake by cell suspensions at different periods of the lag phase correlated with the content of the mitochondrial analogues in them.

Acta Pathol Microbiol Scand {A}, 1979 Mar, 87A(2), 97 - 107
Ascites tumors in CBA mice . 2 . Ultrastructural aspects on ascites conversion; Ryd W et al.; We have studied four syngeneic murine tumors, a fibrosarcoma, a squamous cell carcinoma and their two ascites-converted counterparts, by transmission electron microscopy . The ascites tumors were investigated both as cell suspensions (AA-tumor) and as solid tumor (AS-tumor) . We have also studied the ascites tumors, enzymatically produced cell suspensions of the AS-tumors and solid original tumors by scanning electron microscopy . The two ascites tumors are totally de-differentiated and lack intercellular junctions . This, we think, is a prerequisite for ascites growth . But the ascites tumors show no peculiar ultrastructural features in comparison with other undifferentiated malignant tumors . We found no morphological cell alternations by the enzymatical dissociation procedure used to bring the solid tumors into suspension . Differences between the AS and AA tumors can be ascribed to differences in proliferation rates.

Cancer Res, 1979 Mar, 39(3), 1001 - 7
Development of a metastatic brain tumor model in mice; Conley FK; This study reports an easily accomplished and reliable model of metastatic tumor in the brains of mice . Five experimental groups of female C3H/Bi mice received left intracardiac injections of a syngeneic KHT sarcoma cell suspension (1 X 10(5) cells) and were followed until death . Two groups of mice also received 3,000 rads of radiation to a limited cardiac port 24 hr after tumor injections . All mice were completely autopsied, and the brains were examined both grossly and microscopically . Metastatic brain tumor developed in 60 to 70% of mice; the tumor foci were parenchymal, usually multifocal, and had wide distribution throughout the cerebrum, brainstem, and cerebellum . There was occasional meningeal tumor, but tumor never involved the skull, choroid plexus, pituitary gland, or local extracranial structures . Cardiac irradiation did not increase the number of the mean survival of mice with metastatic brain tumor but did decrease the total tumor burden of individual animals by markedly reducing the incidence of metastatic lung tumor and totally preventing tumor infiltration of the heart . This demonstration of consistently produced blood-borne metastatic brain tumor in mice should provide a valuable research model which will allow the central nervous system to be studied for internal mechanisms and/or external factors which influence the arrest and growth of embolic tumor cells in the brain.

J Neurosurg, 1979 Mar, 50(3), 305 - 11
Macrophages in experimental and human brain tumors . Part 2: studies of the macrophage content of human brain tumors; Morantz RA et al.; The authors have analyzed 47 tumors of the central nervous system (11 glioblastomas, nine meningiomas, three medulloblastomas, 12 assorted primary neural tumors, and 12 brain metastases) for their content of macrophages . Cell suspensions were prepared by enzymatic digestion and macrophages were quantitated by IgGEAC rosette formation . Adsorption of sensitized indicator cells (EA) to sections of tumor was used as a measure to determine the distribution of IgGFc receptor-positive cells within the tumors and to serve as a control for selective release of IgGFc receptor-positive cells by enzyme digestion . The 11 glioblastomas had a mean macrophage content of 45% (range: 8% to 78%), the nine meningiomas had a mean of 44% (range: 5% to 81%), the three medulloblastomas a mean of 6% (range 2% to 15%), and the metastatic tumors a mean of 24% (range: 4% to 70%) . Adsorption of EA demonstrated that IgGFc receptor-positive cells were distributed throughout the tumor mass, although different types of patterns were observed . There was an excellent correlation between the percent of IgGEAC positive cells in suspensions and the extent of EA adsorption to the tumor sections . Compared to systemic neoplasms, most nervous system tumors have a high macrophage content . It is possible that the high macrophage content of brain tumors is related to their immunogenicity, and may be a partial explanation for tha rarity of brain-tumor metastases.

J Invest Dermatol, 1979 Mar, 72(3), 120 - 7
Sebaceous gland differentiation . I . Separation, morphology and lipogenesis of isolated cells from the mouse preputial gland tumor; Potter JE et al.; Single cell suspensions have been prepared, by enzyme digestion, from the mouse preputial gland tumor and separated by flotation centrifugation into populations of different buoyant densities . These populations of cells have been shown by morphological, chemical and biochemical criteria to be in different stages of maturation . Some properties of the separated cells are described.

Anal Quant Cytol, 1979 Mar-Apr, 1(1), 61 - 6
A pattern classification system for automated cervical cytologic screening based on flow microfluorometric analysis; Bentley SA et al.; A data analytic technique is described for use in automated cervical cytology . The method entails the application of a two-dimensional Fourier transform to histogram data obtained by flow microfluorometry and the subsequent use of the Fourier coefficients as parameters for pattern classification . Analyses were performed on 186 samples including material from 62 positive and 124 negative cases . Cell suspensions were stained with propidium iodide and fluorescein isothiocyanate, and red and green cytofluoresence were measured simultaneously . The two-dimensional histogram data were normalized, the Fourier transform was applied, and a multivariate classifier based on 30 coefficients was assembled using a training set of half the original series . Performance was then assessed on the remaining cases . Overall accuracy was 79.6%, with a false-positive rate of 14.8% and a false-negative rate of 31.2% . The potential applicability of this approach as the basis of a practical screening system is discussed.

J Toxicol Environ Health, 1979 Mar-May, 5(2-3), 565 - 73
Kupffer cell suspensions and cultures as a tool in experimental carcinogenesis; Munthe-Kaas AC; Approximately one-third of the cells in the liver are nonhepatocytes . Of these, the Kupffer cells, or phagocytes lining the sinusoids, are of particular significance since environmental carcinogens must first traverse a Kupffer cell barrier before reaching the liver parenchyma . Phagocytosis and subsequent degradation of carcinogens by Kupffer cells lead to their permanent removal . Factors such as membrane receptors, which determine the avidity of Kupffer cells for various substances, would consequently have a decisive role in the primary interaction between carcinogens and Kupffer cells . Likewise, the intracellular lysosomal apparatus, which determines the ability of these cells to degrade various substances, would determine whether these substances can persist in an active form . In vivo data on Kupffer cell clearance of various substances are plentiful . However, to dissect the complex problem of Kupffer cell interaction with carcinogens, a clear-cut in vitro system would certainly be useful . A system for separating Kupffer cells from other types of liver cells and maintaining pure Kupffer cell cultures has been achieved in recent years . Some basic cell biological studies--such as studies of membrane receptors and lysosomal enzyme apparatus--have already been carried out . It could now be rewarding to adopt the system for in vitro studies of Kupffer cell interactions with carcinogens.

J Natl Cancer Inst, 1979 Mar, 62(3), 485 - 91
Immunohistologic evaluation of the lymphoreticular infiltrate of human central nervous system tumors; Wood GW et al.; Forty-five nervous system tumors (9 glioblastomas, 9 meningiomas, 15 assorted primary neural tumors including 3 medulloblastomas, and 12 brain tumors metastatic to the brain were analyzed for their content of lymphocytes, granulocytes, and macrophages . Cell suspensions were prepared by enzymatic digestion; lymphocytes and granulocytes were quantitated by morphology following cytocentrifugation, and macrophages were quantitated by IgG EAC (erythrocyte-antibody-complement) rosette formation . EA (erythrocyte-antibody) adsorption to sections of tumor was employed to determine the distribution of the IgG Fc receptor-positive cells within the tumors and to serve as quality control for selective release of Fc receptor-positive cells by enzyme digestion . The 9 glioblastomas had a mean macrophage content of 41% (range: 5-78%); the 9 meningiomas, 42% (range: 5-80%); the 3 medulloblastomas, 6% (range: 2-15%); and the metastatic tumors, 21% (range: 2-50%) . Lymphocyte contents were variable but generally less than 10% . Most tumors contained less than 10% granulocytes . EA adsorption demonstrated that Fc receptor-positive cells were distributed throughout the tumor mass, although different types of patterns were observed . There was an excellent correlation between the percent EAC rosette-positive cells in suspensions and the extent of EA adsorption to the tumor sections . The significance of the study primarily rests in the demonstration that most nervous system tumors contain high numbers of infiltrating host cells, primarily macrophages.

Anal Quant Cytol, 1979 Mar-Apr, 1(1), 43 - 9
The monodisperse cervical smear: quantitative analysis of cell dispersion and loss with enzymatic and chemical agents; Wolley RC et al.; The proper utilization of flow-through instruments for the automatic detection of malignant cells in human cervical specimens requires that the cells be in the form of a monodisperse suspension . Information regarding the degree of cell dispersion and of cell loss is therefore of critical importance in the evaluation of any procedure used to render cervical specimens monodispe automatic detection of malignant cells in human cervical specimens requires that the cells be in the form of a monodisperse suspension . Information regarding the degree of cell dispersion and of cell loss is therefore of critical importance in the evaluation of any procedure used to render cervical specimens monodispe automatic detection of malignant cells in human cervical specimens requires that the cells be in the form of a monodisperse suspension . Information regarding the degree of cell dispersion and of cell loss is therefore of critical importance in the evaluation of any procedure used to render cervical specimens monodisperse . We have devised a simple method for the simultaneous assessment of these two parameters using smears prepared with the Perkin-Elmer Uni-Smear Spinner . Our quantitative evaluation indicates that none of the 15 enzymatic and chemical agents tested to disperse cervical specimens produced an adequate monodispersed cell suspension without unacceptable cell loss . Electron microscopic evidence is used to illustrate the deleterious effects of some of the agents employed.

J Biol Chem, 1979 Feb 25, 254(4), 1349 - 55
Isolation and characterization of two homoserine dehydrogenases from maize suspension cultures; Walter TJ et al.; Homoserine dehydrogenase in unpurified extracts of maize (Zea mays L.) cell suspensions is inhibited 73% by the feedback regulator threonine; the remaining 27% of the total activity is not affected even by high concentrations of threonine . The threonine-resistant and threonine-sensitive homoserine dehydrogenase activities were separated by affinity chromatography on Blue Sepharose columns, and the two distinct homoserine dehydrogenases were purified . The threonine-resistant enzyme is an Mr = 70,000 dimer of two Mr = 38,000 subunits and the threonine-sensitive enzyme is an Mr = 190,000 dimer containing two apparently different subunits with molecular weights of 89,000 and 93,000 . The threonine-resistant enzyme exhibits normal Michaelis-Menten kinetics and its activity is not affected by any of the amino acid end products of the aspartate pathway . The threonine-sensitive enzyme exhibits positive cooperative kinetics with respect to NADPH and is inhibited by threonine and stimulated by isoleucine . All attempts to affect interconversion of the two purified enzymes have been unsuccessful . Because the purified enzymes correspond to activities present in crude extracts of various maize tissues, it is concluded that the two types of homoserine dehydrogenase are natural in vivo constituents of maize.

Experientia, 1979 Feb 15, 35(2), 168 - 9
Tetrapyrrole biosynthesis from 4,5-dioxovaleric acid in rhodopseudomonas spheroides; Couso R et al.; Prophyrin biosynthesis from 4,5-dioxovaleric acid was studied in cell suspensions of R . spheroides . The experiments show that 4,5-dioxovaleric acid is a far precursor of porphyrins through delta amino laevulinic acid formation in a transmination reaction involving also l-alanine . It differs radically from the classical delta aminolaevulinic acid synthesis using glycine and succinyl CoA as substrates.

Brain Res, 1979 Feb 9, 161(3), 503 - 14
Preparation of viable astrocytes from the developing cerebellum; Cohen J et al.; A cell fraction enriched in viable astrocytes has been prepared from the developing rat cerebellum . The isolated astrocytes were identified by indirect immunofluorescence using antiserum to glial fibrillary acidic protein (GFAP) . In comparison with the low incidence (6%) of GFAP-positive cells in the unfractionated cell suspension from trypsinized cerebellar tissue, these accounted for half of the cells in the final preparation . This was achieved by treatment at 6 days of age with hydroxyurea (an inhibitor of DNA synthesis) which enriched the tissue in GFAP-positive astrocytes at day 8 . At the same time, by selectively removing the heterogeneously sized replicating cells, hydroxyurea treatment allowed resolution of a fraction enriched in GFAP-positive cells using unit gravity sedimentation . The isolated astrocytes differentiated in culture producing, by 3 days in vitro, a dense network of fine GFAP-containing processes.

Biochim Biophys Acta, 1979 Feb 9, 566(2), 253 - 8
The interrelationship of superoxide dismutase and peroxidatic enzymes in the red cell; McMahon S et al.; Activities of superoxide dismutase (superoxide:superoxide oxidoreductase, EC 1.15.1.1) and catalase (hydrogen-peroxide:hydrogen-peroxide oxidoreductase, EC 1.11.1.6) were determined during the course of incubation of red cell suspensions with 1,4-naphthoquinone-2-sulfonic acid . In the absence of glucose, incubation with napthoquinone sulfonate resulted in an inhibition of catalase and superoxide dismutase . The catalase inhibitor, 3-amino-1,2,4-triazole enhanced inactivation of catalase in the presence of naphthoquinone sulfonate and this in turn led to augmented inhibition of superoxide dismutase . The presence of glucose in the incubation medium prevented napthoquinone sulfonate-induced enzyme inhibition in the absence of aminotriazole, but had little effect in the presence of aminotriazole . The relevance of these findings to the cellular interrelationship of peroxidatic enzymes and superoxide dismutase is discussed.

Brain Res, 1979 Feb 2, 161(2), 277 - 91
Cell suspensions from rat olfactory neuroepithelium: biochemical and histochemical characterization; Hirsch JD et al.; Cell suspensions were generated from rat olfactory epithelium by digestion with collagenase and hyaluronidase followed by gentle mechanical disruption . These cell suspensions excluded nigrosin dye and synthesized RNA, protein and carnosine from radiolabeled precursors . Sustentacular cells, repiratory epithelial cells and olfactory neurons but not basal cells could be identified by phase-contrast microscopy . Sedimentation of these cell suspensions at unit gravity in discontinuous gradients of buffered bovine serum albumin resulted in partial separation of the various cell types as indicated by the distribution of several biochemical markers . Olfactory marker protein and carnosine synthetase activity were found in the upper gradient fractions, while carnosinase activity was present predominantly in the lower gradient fractions . Cellular localization of olfactory neuron marker protein and non-neuronal S-100 protein by immunoperoxidase staining of gradient-fractionated cells indicated that neuronal cells were only partially separated from non-neuronal cells by our fractionation techniques . Evaluation of gradient fractionated cells by histochemical staining for carbohydrates demonstrated that secretory Bowman's gland cells were quite efficiently separated from neurons . This study demonstrates the ease with which cell suspensions may be produced from the olfactory epithelium, and emphasizes the importance of utilizing both biochemical and histochemical approaches in studies of mixed populations of cells, particularly when the purity of the cell fractions is a consideration.

J Immunol, 1979 Feb, 122(2), 383 - 91
Helper cells activated by allogeneic H-2K or H-2D differences have a Ly phenotype distinct from those responsive to I differences; Swain SL et al.; Helper activity for the primary in vitro response to sheep erythrocytes was induced by recognition of foreign major histocompatibility antigens . The Lyt phenotypes of helper activity induced by differences in the whole haplotype, K or D antigens, I region antigen, or by differences at the M1s locus were determined . All allohelper cells expressed Ly1 . In a single spleen cell suspension helper activity generated in response to the whole haplotype, I region, or M1s antigens was derived from an Ly2-negative population, whereas helper activity generated to K or D alone was derived from a population of Ly2-positive cells . Mixtures of anti-Ly1 and anti-Ly2 treated populations were unable to generate helper activity in response to K or D differences . Such helper activity was therefore dependent on the presence of Ly12 cells . It was concluded that the Ly phenotype of the helper cells is not determined solely by the T cell function but is influenced by the region of the major histocompatibility complex that is recognized . Possible interpretations of these findings are discussed.

Mol Cell Endocrinol, 1979 Feb, 13(2), 159 - 66
Angiotensin-induced steroidogenesis in rabbit adrenal: effects of pH and calcium; Chiu AT et al.; The effect of variations in pH and Ca2+ on angiotensin II (A-II)-induced steroidogenesis was tested on isolated adrenal glomerulosa cell suspensions . The results show that a reduction in pH from 7.4 to 6.5 produces both a shift to the left of the A-II dose-response curve as well as an increase in maximum steroid production . In contrast, removal of Ca2+ from the incubation medium virtually abolished steroidogenesis to A-II (5 X 10(-9)M(, KCl(10mM) and ACTH (250 microU/ml) . The Ca2+ antagonist D-600, however, was less effective than simple removal of Ca2+ as 10(-4) M was required to block the steroidogenic response to these same agonists . The results indicate that the response characteristics of this system to A-II resemble most closely those seen with isolated arterial smooth muscle - especially rabbit aortic strips.

Nouv Rev Fr Hematol, 1979 Jan 30, 20(4), 585 - 98
{Morphology and deformability of erythrocytes in muscular dystrophy}; Garceau C et al.; In recent years, the presence of red cell morphological abnormalities in patients with Muscular Dystrophy has made the object of numerous, often contradictory reports . A possible source of such confusion may lie in the fact that human erythrocytes are extremely sensitive to morphologic transformations resulting from various manipulations or environmental conditions in vitro . We have examined the morphology and deformability of erythrocytes from 7 patients with Duchenne and 9 patients with Steinert (myotonic) Muscular Dystrophy . To avoid preparation artifacts, fresh, unwashed red cells suspended in their own plasma were examined under phase contrast microscopy for the presence of either echinocytes and stomatocytes . Deformability was measured by filtration of dilute cell suspensions at constant flow rate through nucleopore membranes (nominal pore diameter = 3 micrometer) . No significant difference was found between the patients' cells and those of 22 healthy volunteer controls . We conclude that previously reported abnormalities may have been the result of preparation artifacts . It appears possible, however, that erythrocytes from Muscular Dystrophy patients may be more sensitive than normal ones to certain stimuli originating from red cell manipulations in vitro.

Acta Neuropathol (Berl), 1979 Jan 12, 45(1), 61 - 5
Lymphatic efflux of intracerebrally injected cells; Oehmichen M et al.; Following intracerebral injection of labeled erythrocytes, lymphocytes and/or peritoneal macrophages, cervical and inguinal lymph nodes were subjected to histologic examination . Labeled cells of all cell types were found in the cervical lymph nodes, but they were not observed in the inguinal lymph nodes . No labeled cells were demonstrated in the lymph nodes following intravenous injection of cell suspensions . It is assumed that an efflux of cells occurs in the perineural spaces of the exiting nerve fibers . The anatomic relationships were discussed.

J Biol Chem, 1979 Jan 10, 254(1), 57 - 65
Concomitant induction of phenylalanine ammonia-lyase and flavanone synthase mRNAs in irradiated plant cells; Schroder J et al.; Irradiation of previously dark-grown cell suspension cultures from parsley (Petroselinum hortense Hoffm.) with ultraviolet light caused large, concomitant increases in mRNA activities for two characteristic enzymes of phenylpropanoid metabolism, phenylalanine ammonia-lyase, and flavanone synthase . The rates of enzyme synthesis both in vitro in a reticulocyte lysate and in vivo were quantitated by direct immunoprecipitation of the labeled enzyme subunits . Following a period of about 2 h, during which possible changes were below the limits of detectability, the two mRNA activities increased rapidly in irradiated cells for serveral hours . Phenylalanine ammonia-lyase mRNA reached a peak in activity a few hours earlier than flavanone synthase mRNA . The apparent half-lives of the enzyme activities were about 7 to 10 h for phenylalanine ammonia-lyase and 5 to 7 h for flavanone synthase . These data were used to calculate the expected, light-induced changes in enzyme activity from the measured changes in mRNA activity . The results for both enzymes were in agreement with experimental data, indicating that the light-induced changes in enzyme activity can be explained by changes in the respective mRNA activity . Some data concerning changes in the degree of polyadenylation of the mRNAs and the inhibitory effects of 7-methylguanosine 5'-phosphate are presented.

J Exp Med, 1979 Jan 1, 149(1), 1 - 16
Identification of a novel cell type in peripheral lymphoid organs of mice . V . Purification of spleen dendritic cells, new surface markers, and maintenance in vitro; Steinman RM et al.; Dendritic cells (DCs; 1) have been purified from mouse spleen in good yield . Spleen cell suspensions were floated on dense bovine plasma albumin (BPA) columns, and the low density fraction was adhered to glass (2) . The adherent cells consisted of DCs and immature macrophages most of which eluted in a viable state from the culture dish after overnight incubation . The macrophages were then removed by selective rosetting with opsonized erythrocytes and recentrifugation on dense BPA . This protocol resulted in a purified DC fraction, containing 1--3 X 10(5) DCs/spleen, which was homogeneous and distinctive in its properties . All cells exhibited the phase contrast and transmission electron microscopy (EM) cytologic features that were previously described for freshly isolated adherent DCs . By scanning EM, most purified DCs exhibited a remarkable array of bulbous protrusions of varying length and shape, unlike any other lymphoid cell . All DCs expressed surface Ia and other major histocompatibility complex (MHC)-linked alloantigens . DCs, however, lacked surface Ig and T-cell antigens, and did not bind or interiorize opsonized erythrocytes . Purified DCs have been maintined in vitro for 3 days . Recovery of cultured purified cells was 70% or more of starting cell numbers . When {3H}uridine-tagged DCs were mixed with nonlabeled heterogeneous spleen cells, 70--80% of the labeled DCs were recovered as viable cells 2--3 days later . Purified DCs did not readhere to tissue culture surfaces and did not proliferate, even when cultured with mitogenic doses of concanavalin A and lipopolysaccharide . Finally, DCs did not change their cytologic or surface properties after 3 days of culture . These observations extend the evidence that DCs are a novel cell type and provide useful properties and techniques for their further study.

Exp Cell Biol, 1979, 47(4), 312 - 9
A simple lectin-mediated cell-adhesion method for investigating the cell surface; Guy D et al.; A very simple, rapid and reproducible method has been developed for studying the interaction of lectins with the cell surface . This involves determining the number of adherent cells after shaking cell suspensions in Petri dishes which have had a lectin coupled to their surface using 1-cyclohexyl-3-(2-morpholinoethyl) carbodiimide metho-p-toluene sulfonate . Using concanavalin A coupled to 60 mm diameter dishes and between 1.5 and 2 x 10(6) tumour cells, this adhesion reached a maximum after 10 min shaking . Maximum cell adhesion also varied according to the particular lectin used . Adhesion was absent or was very low if cells were shaken in untreated dishes, or in dishes coupled to bovine serum albumin, or in the presence of the lectin-specific sugar-competitor . Under conditions of maximum cell adhesion, the binding of two different lymphosarcoma lines to four different lectins was very similar, whereas the binding of a carcinoma line to these lectins was completely different from that observed for the lymphosarcomas.

Urol Int, 1979, 34(5), 321 - 9
The endocrine background of human renal cell carcinoma . III . Role of inhibitors of R 5020 binding in tumour cytosol; Bojar H et al.; Cytosol preparations obtained from 9 different human renal cell carcinomas were investigated for the eventual presence of progestin-binding inhibitors which might offer an explanation for the previous failure to demonstrate high receptor levels in the tumour tissue . The inhibitory potency of these preparations was estimated by measuring the decrease of R 5020 binding to uterine progestin receptors in the presence of tumour cytosol . Interestingly, cytosol from human renal cell carcinoma was found to contain progestin-binding inhibitors . The average inhibition of R-5020-receptor interaction amounted to 46% . In only 1 out of 9 cases, binding was completely suppressed . In order to circumvent the inhibitory reaction potentially occurring in cell-free systems, R-5020-binding studies additionally were performed in cell suspension . Out of 7 carcinomas studied using this assay system, 5 did not contain any specific progestin-binding entities . In 1 tumour, receptor-atypical non-saturable binding was observed . Only in isolated cells prepared from 1 other carcinoma, could slight indications for the presence of low concentrations of progestin receptors be detected.

J Immunol Methods, 1979, 28(1-2), 133 - 41
Evaluation of intercellular adhesion with a very simple technique; Bongrand P et al.; Rosetting techniques are widely used to quantify or purify various lymphocytic subpopulations; however, these techniques cannot discriminate between different receptors of similar specificities and different binding strengths, further, they do not provide any information concerning the molecular mechanisms involved in cell-cell adhesion . This paper describes a very simple technique of assaying rosette stability: cell suspensions are driven with known pressure through a calibrated needle with a syringe . Adhesion is quantified before and after this treatment . This procedure did not damage rat peritoneal cells used in a model system . Further, this method yielded fairly reproducible results and allowed a crude estimate of the force involved in the binding of glutaraldehyde-treated sheep red cells (GSRC) or immunoglobulin-coated sheep red cells (IGSRC) by rat macrophages (an average force of 0.8 x 10(-7) Newton was needed to separate 50% of bound IGSRC from macrophages) . Binding and binding strength were found to be independent parameters . Last, this method possibly provided a way of separating two distinct subpopulations of rat macrophages . It is suggested that this technique might be routinely used to refine rosette studies.

Tsitologiia, 1979 Jan, 21(1), 112 - 5
{Effect of polyethyelene glycol on proliferation of cultured Chinese hamster cells}; Zaitseva VE et al.; Chinese hamster cells in suspension were treated with PEG 4000 for 20 min . It was found that cell size began to diminish already when a 5% PEG solution was used, and reached the minimal value in a 20% PEG solution . A pronounced cell death was observed when PEG concentration exceeded 20%, but cells that survived retained their proliferation potential . It is concluded that the cell death results from hypoosmotic shock when cell suspension in PEG solution is diluted.

Environ Mutagen, 1979, 1(4), 391 - 8
The effect of 2,4-diaminotoluene and isomers of dinitrotoluene on unscheduled DNA synthesis in primary rat hepatocytes; Bermudez E et al.; The important industrial chemicals 2,4-dinitrotoluene (DNT) and 2,4-diaminotoluene (DAT) are hepatocarcinogens in rats . Technical grade DNT contains approximately 76% 2,4-DNT, 19% 2,6-DNT, and lesser amounts of the other isomers . The ability of 2,4-DAT, technical grade 2,4-DNT, and the purified isomers 2,3-DNT, 2,4-DNT, 2,5-DNT, 2,6-DNT, 3,4-DNT and 3,5-DNT to damage the DNA of primary rat hepatocytes was examined . Male Fischer-344 rats were perfused in situ, single cell suspensions were obtained after liver dissociation, and cultures of these cells were treated in the presence of 3H-thymidine . Autoradiography was employed to visualize label incorporation following repair of DNA . At the nontoxic (as judged by cell morphology) doses of 1 x 10(-4) M and below, only 2,4-DAT induced a significant response (ie an average greater than 5 grains net/nucleus) . The activity seen with 2,4-DAT suggests that damage to the DNA of the hepatocytes may play a role in its carcinogenic activity and is consistent with the proposal that the induction of DNA repair in primary hepatocytes is of value in predicting the activity of aromatic amino compounds . However, the carcinogenic activity of the dinitrotoluenes was not reflected as DNA repair in the isolated hepatocyte, indicating that additional factors involving the whole animal also play a role in the mechanism of action of DNT.

Acta Obstet Gynecol Scand, 1979, 58(6), 543 - 6
Heterogeneous response of disseminated human ovarian cancers to cytostatics in vitro; Trope C et al.; Cell suspensions from nine human ovarian primary cancers, their metastases and ascitic cells were treated in vitro with amethopterin and melphalan . Effects were measured by incorporation of H3-TdR or H3-UdR into the cells . There was significant heterogeneity of cytostatic effects on cells from the three sources in a given patient . Ascitic cells did nt represent a "mean" of the cancer cell clones . The implications of these findings should be considered if cytostatic in vitro prediction tests are used to guide cytostatic treatment of patients.

Arch Exp Veterinarmed, 1979, 33(4), 499 - 512
{Production of primary cell cultures on a semi-industrial scale . 1 . Modification of the trypsinization procedure--possible means to improve cell yield}; Beyer R et al.; To produce large quantities of primary cell suspensions on efficient technique is described which is named "Biomix-Method" . By this technique first tissue mince is performed automatically using tissue amounts between 300 g and 500 g . Trypsinization takes place in a three-litre trypsinization vessel using a stirring mechanism according to a defined trypsinization mode . In regard to optimal cell seeding concentration and a justifiable productivity one kidney of newborn or suckling calf yields 6--9 1 cell suspension and that of piglet 1,8-2,3 1, respectively . Proliferation behaviour and effectivity of primary cells are discussed and compared with other cell systems.

J Supramol Struct, 1979, 11(4), 563 - 77
Production of monoclonal antibodies against a cell surface concanavalin A binding glycoprotein; Starling JJ et al.; Concanavalin A-binding (Con-A)-binding cell surface glycoproteins were isolated, via Con A-affinity chromatography, from Triton X-100-solubilized Chinese hamster ovary (CHO) cell plasma membranes . The Con A binding glycoproteins isolated in this manner displayed a significantly different profile on sodium dodecyl sulfate--polyacrylamide gels than did the Triton-soluble surface components, which were not retarded by the Con-A-Sepharose column . {125I}-Con A overlays of the pooled column fractions displayed on sodium dodecyl sulfate--polyacrylamide gel electro-phoresis (SDS-PAGE) demonstrated that there were virtually no Con A receptors associated with the unretarded peak released by the Con A-Sepharose column, whereas the material which was bound and specifically eluted from the Con A-Sepharose column with the sugar hapten alpha-methyl-D-mannopyranoside contained at least 15 prominent bands which bound {125I}-Con A . In order to produce monoclonal antibodies against various cell surface Con A receptors, Balb/c mice were immunized with the pooled Con A receptor fraction . Following immunization spleens were excised from the animals and single spleen cell suspensions were fused with mouse myeloma P3/X63-Ag8 cells . Numerous hybridoma clones were subsequently picked on the basis of their ability to secrete antibody which could bind to both live and glutaraldehyde-fixed CHO cells as well as to the Triton-soluble fraction isolated from the CHO plasma membrane fraction . Antibody from two of these clones was able to precipitate a single {125I}-labeled CHO surface component of approximately 265,000 daltons.

Arch Geschwulstforsch, 1979, 49(6), 508 - 21
{In-vitro effect of X-irradation on respiration and glycolysis of Ehrlich-ascitic carcinoma cells of the mouse--an experimental comparison with the mouse tumour-tetanus assay (author's transl)}; Negelein E et al.; Depending on the dose of X-rays, in-vitro irradiation of Ehrlich-ascitic carcinoma cells of the mouse affected both respiration and glycolysis . 15,000 R irradiation suppressed the aerobic and anaerobic energy metabolism rather strongly followed by a reduction of the "take" and growth of the subcutaneously injected tumour cells, as opposed to the growth behaviour of non-irradiated cells . In analogy, tetanus mortality rates were reduced in the mouse tumour-tetanus assay with 15,000 R irradiated cells . On the other hand, irradiation with 2,000 R of Ehrlich carcinoma cells resulted in unchanged rates of respiration and glycolysis, in spite of the strongly limited growth capacity of the tumour cells . The tumour-tetanus assay of the mouse showed good correlation with subcutaneous tumour growth; no such correlation was found in the tetanus assay and the manometric values of respiration and glycolysis with 2,000 R irradiated tumour cells.--After subcutaneous injection of mixed cell suspensions consisting of 1 x 10(5) viable and 1 x 10(6) 15,000 R irradiated Ehrlich-ascitic carcinoma cells as well as of 3 x 10(2) tetanus spores per single dose, we observed similar rates of tumour growth, or tetanus mortality, respectively, if 1 x 10(5) viable tumour cells alone were administered together with 3 x 10(2) tetanus spores, without addition of irradiated tumour cells.

Am J Hematol, 1979, 6(4), 295 - 311
Quantitative evaluation of antibody-dependent lymphocyte-mediated lysis of human red cells; Kurlander RJ et al.; The ability of lymphocytes to lyse human red cells coated with anti-D antibody was assessed by measuring 51 Cr release from labeled red cells incubated with peripheral blood leukocyte suspensions from 12 normal donors . Mixed mononuclear cell suspensions (containing monocytes and lymphocytes) from all donors produced lysis of sensitized red cells . Treatment with carbonyl iron reduced monocyte concentration to less than 1.2% in all donors, as measured by morphologic criteria, esterase staining and ingestion of latex particles . Lysis of red cells following monocyte depletion was markedly reduced in 8 of the 12 donors . Despite depletion of monocytes, unchanged or increased lysis was noticed with the leukocytes of the remaining 4 donors . This lysis was due to lymphocytes, not to residual monocytes . If target red cells were treated with papain or trypsin prior to sensitization, marked lysis occurred with lymphocytes of all donors, including those which did not lyse unmodified red cells . Direct cytolysis of sensitized red cells during contact with small lymphocytes was recorded using microcinematography, which confirmed the role of lymphocytes in mediating lysis . Lymphocyte-mediated lysis of red cells increased with mounting levels of antibody sensitization regardless to prior treatment with papain . Papain increased antibody coating per red cell, yet lysis per molecule of antibody bound was also increased . Lysis was inhibited by IgG1 and IgG3 in the fluid phase but not by IgG2 or IgG4 . At an equivalent level of antibody sensitization lysis was augmented by concurrent coating of the red cells with C3b, C3d and/or C4b, though these components could not produce lysis in the absence of antibody coating.

J Cancer Res Clin Oncol, 1979, 95(3), 273 - 80
Incorporation studies of nucleic acid precursors in gastric cancer: an attempt in individualized chemotherapy; Schlag P et al.; Measurements of the rate of incorporation of radioactively labeled nucleic acid precursors into the DNA and RNA of gastric carcinoma cell suspensions indicated variable rates of proliferation for the tumors . The rate of incorporation generally correlates to the cytological level of differentiation of the carcinoma . Reduced differentiation of the tumors showed a corresponding increase in the rate of proliferation . Knowing the proliferation-dependent effect of most cytostatica, this results in a resistance to cytostatica of highly differentiated gastric cancers . The nucleic acid synthesis of proliferatively active tumors could only be partially inhibited by the cytostatica tested (5-fluorouracil, adriamycin) . Carcinomas with metabolic possibility for compensation of the active mechanism of the cytostatica were biochemically resistant . Due to the resulting methodical problems and unaccountable patient-dependent causes of resistance, a conclusive statement about cytostatica-sensitive tumors is difficult to make in incorporation studies.

Bull Cancer, 1979, 66(3), 217 - 28
Distribution and consequences of cell suspensions following intralymphatic infusion; Juillard GJ et al.; The fate and consequences of intralymphatic injections of cells was investigated in dogs . The distribution of intact radiolabeled cells was determined in vivo by whole body gamma scanning . Comparison of distributions resulting from intralymphatic, subcutaneous, intradermal and intravenous routes of administration showed that the distribution and duration of radiolabel in various organs varied with the route of administration . Following intralymphatic injection, radiolabel was concentrated in first echelon lymph nodes draining the site of injection and was retained in these nodes for over 4 weeks . Histologic studies showed intense cortical and paracortical lymphopoiesis to be associated with the retention of intralymphatically injected tumor cells by first echelon lymph nodes . Serial histologic examination of lymph nodes from intralymphatically injected inbred beagles revealed that the consequent lymphopoiesis persisted for 5 weeks . In vitro evaluation of peripheral blood and lymph node lymphocyte cytotoxicity to the injected cells indicated that retention and nodal lymphopoiesis was associated with the development of direct lymphocyte cytotoxicity . The effects of concommitant tumor burden, cytotoxic drugs and ionizing radiation were also investigated and suggest that the therapeutic potential for use of the intralymphatic route has not yet been realized.

Adv Exp Med Biol, 1979, 117, 401 - 21
Studies on the mechanism of estradiol uptake by rat uterine cells and on estradiol binding to uterine plasma membranes; Muller RE et al.; A method for the preparation of viable uterine cell suspensions is described . Using this system the kinetics of estradiol uptake were studied in order to asses whether the steroid enters uterine cells by passive diffusion (1) or protein mediated diffusion (2) . The data presented show that a) the rates of estradiol entry are nonsaturable; b) temperature dependence of uptake kinetics gives a linear Arrhenius plot; c) E2-6-CMO-BSA does not inhibit 3H-E2 uptake; d) uterine plasma membranes do not contain specific estrogen binding sites . Thus, estrogen uptake occures by passive diffusion.

Oncology, 1979, 36(2), 49 - 54
Variations in the level of haematogenous antitumour immunity during progressive tumour growth and spontaneous blood-borne metastatic spread; Proctor JW et al.; Inbred DBA2 mice bearing the syngeneic 1699 mammary tumour in the hind limb were challenged intravenously with 125IUdR-labelled single 1699 cell suspensions, and the amount of radioactivity in the lungs compared 20--24 h later with that in the lungs of normal mice or in those of mice bearing the antigenically unrelated syngeneic SaD2 tumour . An immunologically specific decrease in radioactivity was evident at variable periods of time after tumour induction, depending on the number of cells used to induce the leg tumours, but fell below that in normal mice as the leg tumours progressed beyond a weight of approximately 1 g . As assessed by microscopic scanning of serial histological sections of the same lungs the incidence of spontaneous metastases rose to between 80 and 100% immediately the amount of cell loss from the lungs of the tumour-bearing mice reached that of the normal controls . This extremely rapid series of events does not allow a definitive conclusion as to whether immunity failed and led to metastatic spread or vice versa, but does underline the strong association of immunity with the blood-borne dissemination of tumour cells in this tumour system . Following excision of tumours, in no instance was immunity detected 14 days later, and in a single experiment did not reach detectable limits until 25 days after excision, at a time when the lung metastases were observed mostly to have regressed spontaneously.

Acta Radiol Diagn (Stockh), 1979, 20(1), 1 - 12
Effect of ionic and non-ionic contrast media on red cell deformability in vitro; Aspelin P; The effect on red cell deformability from solutions of the ionic contrast media diatrizoate, iocarmate and metrizoate and the non-ionic metrizamide and hypertonic saline (1.5 osm) was investigated by measuring the flow rate of 10% red cell suspension (VRBC) and of plasma (Vplasma) through Nucleopore sieves of 5 micrometer in diameter . By calculating the relative flow rate Vrel (VRBC/Vplasma) the deformability of the red cell was quantified . Both the contrast media solutions and the hypertonic saline solution decreased the Vrel, indicating an increased rigidity of the red cell . The increased rigidity was due mainly to the osmotic effect . The higher the osmolality, the more the deformability was reduced . The low osmotic metrizamide induced a smaller reduction in red cell deformability compared to ionic media of high osmolality in iodine-equivalent concentration.

J Environ Pathol Toxicol, 1979 Jan-Feb, 2(3), 625 - 32
Chromosome lateral asymmetry: a sensitive assay for screening teratogenic agents; Tucci SM et al.; Pregnant albino mice were administered (ip) embryotoxic doses of three individual teratogens: bromodeoxyuridine, hydroxyurea and mitomycin C on day 10 of gestation . Embryos were removed 4 hr later, a cell suspension was prepared and cultured in the presence of colcemid . Metaphase chromosome spreads were subjected to standard G-banding procedures, and the occurrence and frequency of lateral asymmetry (unequal banding of sister chromatids) was monitored . Embryotoxic levels of all three teratogens produced an increase in the number of asymmetries/karotype . For one of these (mitomycin C), the observed increase was dose-dependent.

J Immunol Methods, 1979, 25(1), 55 - 60
The use of {125I}C1q subcomponent for the measurement of complement binding antibodies on cell surfaces; Shepherd PS et al.; An assay using 125I-labelled human C1q has been developed for the measurement of complement fixing antibodies bound to cell monolayers or cell suspensions . The method has been adapted for use either during or after sensitisation of the cells with antiserum, is simple to perform and does not require require prelabelling of the target cells.

Infect Immun, 1979 Jan, 23(1), 133 - 9
Viral etiology of age-dependent polioencephalomyelitis in C58 mice; Martinez D et al.; The etiology of immune polioencephalomyelitis (IPE) and the mechanisms of resistance to IPE induction were investigated in C58 mice . IPE was found to be induced by a lipid-solvent-sensitive, filterable replicating agent present in line Ib leukemic cell suspensions . IPE was serially transmitted in immunosuppressed mice with filtered extracts of spleens from diseased animals . The IPE-inducing activity of Ib cell extracts was abolished by chloroform or deoxycholate . Gel filtration of Ib cell extracts showed that the IPE agent has a molecular weight of at least 10(7) . Electron microscopy of the active fractions from columns and of spinal cord extracts from mice with IPE revealed a virus-like particle, 40 nm in diameter, which is probably the IPE revealed a virus-like particle, 40 nm in diameter, which is probably the IPE agent . Administration of cyclophosphamide at various times after challenge increased the incidence of IPE in mice, suggesting that IPE is not autoimmune mediated . Immunosuppression resulted in maintenance of high levels of IPE agent in the central nervous system tissue, while immunization resulted in low levels . Moreover, immunized mice produced neutralizing antibodies . These data suggest that antibodies help restrict the amount of IPE agent in the nervous tissue, and that this restriction is required for resistance to IPE induction in C58 mice.

Adv Shock Res, 1979, 2, 129 - 36
Alterations in insulin action by endotoxin in vitro; Spitzer JA et al.; Fat cells isolated from epididymal fat pads of Sprague-Dawley rats were exposed to E coli endotoxin in vitro, and after washing the ensuing alterations in glucose oxidation and antilipolysis were studied . Although endotoxin (500 microgram/ml) exhibited an insulin-like effect on basal glucose oxidation, it diminished insulin stimulation of glucose oxidation, seemingly inducing an insulin-resistant state . On the other hand, identical doses of insulin elicited significantly greater antilipolytic effects in endotoxin-treated cells, than in untreated cells . Thus, endotoxin exposure (in a range of 0.05-200 microgram/0.5 ml cell suspension) rendered adipocytes more sensitive to the antilipolytic effect of insulin . Results of this study indicate that the different physiologic actions of insulin on adipocytes are not affected in a uniform manner by endotoxin exposure in vitro.

Acta Physiol Acad Sci Hung, 1979, 54(4), 401 - 4
Effect of prostaglandins on hypothalamic-pituitary-testicular function in vitro; Vermes I et al.; The effect of prostaglandins (PG) A1, E1, E2 and F2 alpha in the concentration range of 10(-7)--10(-4) M were studied in vitro on a rat hypothalamic tissue, collagenase-digested isolated anterior pituitary cell and Leydig cell suspension system by measuring the testosterone production of incubated Leydig cells . PGs did not change the testosterone production and the hCG sensitivity of the Leydig cells, nor the LH secretion and the LHRH sensitivity of the anterior pituitary cells . PGE2 at concentrations of 10(-6), 10(-5) and 10(-4) M significantly increased the hypothalamic tissue-induced pituitary-testicular activation, and this stimulatory effect of PGE2 was dose dependent . PGA1, PGE1 and PGF2 alpha did not alter hypothalamic LHRH release measured in vitro . The results suggest that PGE2 has a direct stimulatory effect on hypothalamic LHRH release.

Haemostasis, 1979, 8(3-5), 183 - 92
Platelet interactions with the endothelium and the subendothelium: the role of thrombin and prostacyclin; Cazenave JP et al.; The adherence of 51Cr-labeled platelets to rabbit aortae everted on probes rotated in platelet-red cell suspensions has been measured . Platelet adherence to the subendothelium exposed by passage of a balloon catheter before everting the aortae was inhibited by compounds that increase platelet cyclic AMP levels (PGE1, PGI2 or dipyridamole) . These agents, however, did not abolish platelet adherence to the subendothelium . Aspirin treatment of the vessel wall was used to block PGI2 production; platelet adherence to the surface of the 'undamaged' aorta and the subendothelium was studied following this treatment . Since aspirin treatment of the 'undamaged' vessel wall did not cause platelets to adhere to it, it seems unlikely that PGI2 formation by the vessel wall is the mechanism that prevents platelet adherence to normal endothelium . In addition, PGI2 formation by the vessel wall does not appear to influence platelet adherence to the subendothelium, since adherence was not increased by aspirin treatment of the damaged wall . Thrombin treatment of the 'undamaged' vessel wall increased platelet adherence to the surface, but the adherent platelets were seen to be adherent only to small areas where the endothelium was lost or damaged . Heparin reversed the effect of thrombin . Similar results were found when the subendothelium was exposed to thrombin or thrombin and heparin.

Dermatologica, 1979, 159(5), 386 - 92
{Enzyme cytochemical and immunocytological differentiation of infiltrative cells in the skin in mycosis fungoides}; Buchner SA; In 4 patients with mycosis fungoides in the praemycotic, infiltrative and tumour stage of the disease, a differentiation and functional characterization of the infiltrate cells, obtained from cell suspensions and cutaneous smears, was carried out by means of enzyme cytochemical and immunological methods . The lymphocyte-associated acid esterase is considered to be a marker for mature T-cell populations . Apart from monocytes and histiocytes, acid esterase-positive small lymphocytoid cells with T-cell properties are found in the praenycotic stage . In the tumour stage, large lymphocytoid cells become increasingly prevalent, they show no acid esterase activity, but an intracytoplasmatic-localized reaction in the acid phosphatase activity . On the basis of the cytochemical pattern, it is assumed that these cells represent proliferating lymphoblasts.

Dermatologica, 1979, 159(2), 125 - 31
{Manifestation of a malignant lymphoma of high grade malignancy in the terminal stage of mycosis fungoides . Enzyme-cytochemical and immunocytological investigations (author's transl)}; Buchner S et al.; Report on a patient with mycosis fungoides, in whom after a long course the disease developed rapidly into a malignant lymphoma of high grade malignancy . The diagnosis was confirmed by cytomorphological and enzyme-cytochemical methods (demonstration of hydrolytic enzymes in cryostat sections, cutaneous smears and cell suspensions extracted from skin lesions), as well as by immunocytological methods (differentiation of lymphocyte sub-populations) . In the tumour stage of mycosis fungoides, a polymorphous infiltrate composed of lymphocytoid and monocytoid cells prevailed, while a proliferation of lymphoblastic cells was present in the terminal stage of the disease . These cells showed no longer the properties of mature lymphocytes and differed also in their enzyme-cytochemical pattern.

Scand J Immunol, 1979, 9(5), 429 - 40
Lymphocyte subpopulations in man: characterization of human killer cells against allogeneic targets sensitized with HLA antibodies; Johnsen HE et al.; Human killer cells mediating antibody-dependent cytotoxicity against allogeneic lymphoblasts presensitized with HLA antibodies have been studied by rosette fractionation experiments . Enriched and/or depleted cell suspensions have been tested in dose-response studies . Two different populations can act as killer cells . The major cytotoxic capacity is retained among T cells with high-avidity Fc receptors, whereas a minor cytotoxic capacity was found among non-T cells with high-avidity Fc receptors . These two populations have different dose-response curves, indicating different effector mechanisms.

J Immunol Methods, 1979, 26(4), 337 - 44
A pen smear technique for assays of rosette-forming lymphocytes; Campbell AC et al.; A simple technique is described for the preparation of permanent stained smears of human E-rosette lymphocytes . Smears of the cells suspended in foetal calf serum were drawn as thin strips on slides with a pen nib . Such smears, after Romanowsky staining, and incorporating latex-particles phagocytosis as a marker for non-lymphoid cells, show excellent rosette preservation and permit easy distinction and counting of rosetting lymphocytes, non-rosetting lymphocytes, monocytes and granulocytes . The percentages of rosette-forming lymphocytes estimated on such smears correspond closely to those obtained from counts made on viable cell suspensions.

Steroids, 1979 Jan, 33(1), 97 - 113
Uptake and metabolism of female sex steroids by isolated small neurons and other cell fractions from the rat medial basal hypothalamus; Lloyd RV et al.; Rat medial basal hypothalami (MBH) and sections of cerebral cortex (CC) were dissociated with trypsin to prepare single cells and subcellular fractions . They were then separated into four fractions on a discontinuous sucrose gradient . The small neurons in Fraction D were highly purified . Fraction A had synaptosomes, myelin and other cell particulates . Fraction B had glial cells, neurons and a few synaptosomes . Fraction C had large neurons and red blood cells . All four fractions contained LHRH, but most (62.5%) of this hormone was present in Fraction A . Dissociated cell suspensions were incubated with {3H}-steroids, with and without a 100-fold excess of unlabeled steroids, then separated on sucrose gradients . In most fractions the total uptake and specific uptake of {3H}-progesterone, {3H}-5 alpha-pregnane-3,20-dione (5 alpha-dihydroprogesterone) and {3H}-17 beta-estradiol were greater for the dissociated cells from the MBH than the CC . The dissociated cells and cell particulates in all four fractions from the MBH and CC metabolized progesterone, 5 alpha-dihydroprogesterone and 17 beta-estradiol . These results indicate that hypothalamic neurons contain small amounts of LHRH and retain the ability to take up and metabolize progesterone, 5 alpha-dihydroprogesterone and 17 beta-estradiol.

Transplantation, 1979 Jan, 27(1), 45 - 8
Diversity of expression of H-2 antigens on mouse liver cells demonstrated by immunoferritin labeling; Parr EL; Antigens of the mouse H-2 locus were studied on isolated liver cells by immunoferritin labeling . Cell suspensions were obtained by gentle homogenization of mouse livers that had been perfused with hypertonic sucrose to loosen cell junctions . Hepatocytes showed sparse labeling of H-2 antigens on the order of 1% of that present on peritoneal monocytes . The slight hepatocyte labeling appeared to be specific for the H-2 locus, since there was essentially no label on congenic control hepatocytes . Other cells in the liver cell preparations were more heavily labeled . Bile duct epithelial cells showed heavy labeling on their lateral surface membranes, but none on their apical brush borders . The preparations contained another nonparenchymal cell type that was densely labeled, but it was not positively identified . Spleen lymphocytes added to liver homogenates and carried through the cell isolation procedure with liver cells showed typically heavy ferritin labeling . These observations suggest that the expression of histocompatibility antigens by tissue cells is likely to be quite variable.

Scand J Immunol, 1979, 10(5), 453 - 63
Age-dependent changes in the electrophoretic mobilities of human blood lymphocytes; Wioland M et al.; The distribution of the anodic electrophoretic mobilities (EPM) of human peripheral blood lymphocytes was determined for lymphocytes isolated from umbilical cord blood and from blood of individuals 6 months to 93 years of age . The distribution was bimodal in infants up to 2 years of age and suggested a small percentage of cells with a mobility of 0.95 micrometer s-1 V-1 cm . this value was chosen to discriminate between low-mobility cells (LMCs) and high-mobility cells (HMCs) . The relative percentage of LMCs increased from birth to 2 years and two types of LMCs could be distinguished . The distribution was unimodal and asymmetric in children and adults and nearly Gaussian in aged people . Substantial differences between the distributions of the lymphocyte EPMs were seen on comparison of the histograms for individuals of similar ages . The analysis of the distribution of the lymphocyte EPMs on cell suspensions enriched in, or depleted of T or B cells confirmed the mobility of most T cells to be higher than the mobility of most B cells, whatever the age of the individual . The distribution of lymphocyte EPMs determined in the same adult over a 6 year period showed minor variations.

Differentiation, 1979, 14(3), 167 - 74
Experimental studies on hemopoiesis in the pronephros of Rana pipiens; Carpenter KL et al.; Embryogenesis of hemopoietic cell populations in the pronephros of Rana pipiens was examined during embryonic and early larval development . Differential cell counts of Wright-Giemsa-stained cell suspensions demonstrated that granulopoiesis is the predominant hemopoietic activity in the pronephros, erythropoiesis accounts for a minor component of the hemopoietic activity (less than 10%), and lymphopoiesis within the organ is negligible . Microdensitometric analysis of Feulgen-DNA stained granulocyte populations in pronephroses from larvae that had received chromosomally labeled pronephric analgen transplants between 84 and 96 h of development demonstrated that hemopoiesis in this organ is dependent on colonization by an extrinsic hemopoietic stem cell . A similar analysis of pronephric hemopoiesis in larvae which had received chromosomally labeled, presumptive ventral blood island transplants between 62 and 67 h of development, indicates that granulopoietic cells are not derived from the embryonic blood islands . It is proposed that the pronephros may be the initial site of granulocyte differentiation during early embryogenesis . Although the embryonic origin of the hemopoietic stem cell is unknown, indirect evidence from this study indicates a dorsal stem cell compartment.

Ontogenez, 1979, 10(4), 405 - 10
{Interaction of T- and B-cells in the secondary response to ram erythrocytes in mice of different ages}; Ekhneva TL; The spleen cells from old primed donors were found to produce lesser secondary response, as compared with the cells of young animals, in the system of adaptive transfer on the CBA mice . In the experiments with extermination of T-or B-cell population in the cell suspension by means of theta-or anti-b-sera it was established that the memory to the antigen used (ram ethyrocytes) was carried by both T- and B-cells but the T-cell component played the leading role in this system . The primed cells from old animals proved to be more sensitive to defects of cellular interactions.

Clin Exp Immunol, 1979 Jan, 35(1), 25 - 32
Regulatory T cells in the humoral response of protein deficient mice; Price P et al.; Cell suspensions from the spleen or thymus of mice fed normally or mice that were protein deficient were injected into mice from each dietary group and also syngeneic nudes . Antigen, polyvinyl pyrrolidone (PVP), was injected at the stage of cell transfer and the antibody titres of the recipient animals were compared with those of control animals given only antigen . The regime was repeated using cell suspensions from donor animals which had been primed with antigen . These experiments showed that spleen cells were suppressive only when transferred from deficient to normal mice . Thymocytes generally lacked suppressive effects, except when given to irradiated mice also injected with "normal" spleen cells . However, thymocytes from deficient mice were marginally enhancing in nude mice, deficient mice and older "normals" . To explain these results, it is suggested that responses to PVP are determined by distinct "suppressor-inducing" and "suppressor" T cells which act via helper T cells . The latter probably affect B cells directly and largely influence IgG production . It also appears likely that the ratio of helper to suppressor (inducer and effector) T cells is increased by protein deficiency.

Int Arch Allergy Appl Immunol, 1979, 58(3), 295 - 301
Delayed type hypersensitivity to allogeneic cells in mice . II . Cell transfer studies; Smith F et al.; Sensitivity to allogeneic cell surface antigens was transferred to naive mice by lymphoid cells from sensitized mice . Sensitivity was detected 24-48 h after antigen challenge and was associated with a mononuclear cell infiltration . The cells responsible for transfer were T lymphocytes as demonstrated by successful transfer with cell suspensions enriched for T lymphocytes, and by abrogation of transfer following treatment with anti-Thy-1.2 serum and complement . Both Lyl+ and Ly2+3+ bearing T cells were involved . Removal of Ia+ cells had no effect on the ability of sensitized lymphoid cells to transfer the reaction to naive mice.

J Neurol Neurosurg Psychiatry, 1979 Jan, 42(1), 29 - 34
Lymphocyte subpopulations in thymus and blood from patients with myasthenia gravis; Aarli JA et al.; Cell suspensions were prepared from hyperplastic thymic tissue and lymphoepithelioma from patients with myasthenia gravis and from presumed normal thymic tissue obtained at cardiac surgery . The mononuclear cells were examined for surface markers . The mean percentages of both T lymphocytes and Fc receptor-carrying lymphocytes were similar in the three groups, whereas there was an increase in C receptor-carrying lymphocytes in the samples from myasthenic patients . Sections from the thymus gland were examined for T and B markers . In the hyperplastic thymus and in lymphoepithelioma, the T lymphocytes were distributed diffusely throughout the cortex and the medulla; in the normal thymus they were predominant in the cortex . The mean percentage of T and B lymphocytes in peripheral blood from patients with myasthenia gravis was normal . Thymectomy involved a transitory decrease in T lymphocytes with a corresponding increase in B lymphocytes.

Am J Dermatopathol, 1979 Fall, 1(3), 215 - 21
Histochemical analysis of Langerhans' cells; Berman B et al.; Single cell suspensions of epidermal cells from guinea pigs were analyzed histochemically for the presence of the following enzymes: 5'-adenosine triphosphatase, nonspecific esterase, specific esterase, myeloperoxidase and leukocyte alkaline phosphatase . A population of cells was positive for nonspecific esterase, leukocyte alkaline phosphatase, and 5'-adenosine triphosphatase . This population was identified as Langerhans' cells because the number of cells stained for these enzymes paralleled the number of Langerhans' cells in the suspension . These same enzymes were shown to be present in guinea pig leukocytes of the mononuclear-phagocytic series, suggesting that they and Langerhans' cells may have a precursor in common.

Scand J Immunol, 1979, 10(3), 229 - 35
Rat memory T lymphocytes . II . Differences in macrophage-dependent activation shown by Actinomyces viscosus antigens and by mitogens, using silica in vitro; Burckhardt JJ; Protein-coated silica, a macrophage toxin, was used to assess the requirement for accessory cells in the induction of an in vitro proliferative response to (i) antigens from Actinomyces viscosus and (ii) the mitogens conconavalin A (Con A) and phytohaemagglutinin (PHA) . T cells were obtained from RIC-Sprague-Dawley rats primed in vivo with A . viscosus Nyl by splenectomy and filtering the spleen cell suspensions through Degalan Ig-anti-IgG columns . In the presence of 100 microgram silica/ml during 4 days of culture, the proliferative response of T lymphocytes was not diminished . In contrast, when the T cells were precultured with silica for 24 h, washed, and subsequently cultured with the antigen fractions, antigen-induced proliferation was abolished . This procedure, however, had no influence on mitogen-induced proliferation was abolished . This procedure, however, had no influence on mitogen-induced T-cell activation.It is therefore concluded that the antigen-dependent anamnestic in vitro response (but not activation by mitogens) of rat T lymphocytes needs help from silica-sensitive macrophages.

Endocr Res Commun, 1979, 6(2), 107 - 21
Regulation of ornithine decarboxylase activity in rat ovarian cells in vitro; Piik K et al.; Incubation of rat ovarian cell suspension with human choriogonadotropin (hCG) caused a marked enhancement of ornithine decarboxylase (EC 4.1.1.17) activity after a lag period of several hours . Even though ovarian ornithine decarboxylase could be induced in minimum essential medium by the hormone alone, supplementation of the medium with various sera greatly enhanced the stimulation of the enzyme activity . All the sera tested (human, fetal calf and horse) were able to stimulate ornithine decarboxylase activity even in the absence of hCG . Maximum stimulation of the enzyme activity by hCG and/or serum occurred in ovarian cell suspensions prepared from 30 to 33-day-old rats . There was a close correlation between the stimulation of ornithine decarboxylase activity and the accumulation fo cyclic AMP in response to the administration of the hormone (in the presence or absence of serum) . However, while various sera alone markedly enhanced ovarian ornithine decarboxylase activity in vitro they, if anything, only marginally stimulated the accumulation of cyclic AMP and the secretion of progesterone in ovarian cells in the absence of gonadotropin . A similar dissociation of the stimulation of ornithine decarboxylase activity from the production of cyclic AMP and progesterone was likewise found when the ovarian cells were incubated in an enriched medium (M199) supplemented with albumin and lactalbumin hydrolysate in the absence of the hormone . Under these culture conditions ornithine decarboxylase activity was strikingly enhanced, greatly exceeding the stimulation obtained with various sera, while the accumulation of cyclic AMP and the secretion of progesterone remained virtually unchanged . Specific inhibition (up to 90%) of gonadotropin-induced ornithine decarboxylase activity by difluoromethyl ornithine or 1,3-diamino-2-propanol had little effect on the ability of the ovarian cells to respond to the hormone with increasing production of cyclic AMP and progesterone . While showing that rat ovarian ornithine decarboxylase can be induced in vitro by choriogonadotropin or various sera, our results indicate that the activation of the enzyme involves at least two different mechanisms: (i) One (in response to gonadotropin) involving a prior stimulation of cyclic AMP production, and (ii) another (in response to serum) that is not associated with increases in the accumulation of the cyclic nucleotide.

Acta Haematol, 1979, 61(5), 251 - 7
Early increase of cyclic adenosine monophosphate level induced by erythropoietin on rabbit bone marrow cell suspensions; Chiuini F et al.; The effects of an erythropoietin (Ep)-rich plasma fraction and of a commercial preparation of purified Ep (Step I) on the cyclic adenosine monophosphate (cAMP) levels of suspended rabbit bone marrow cells at different incubation times (up to 10 min) were investigated . Both Ep preparations caused an early increase in cAMP concentration: using the plasma fraction a significant increase was found at the 6th, 7th, 9th and 10th min of incubation, whereas the purified Ep produces a significant increase at all incubation times, starting from 1 min . No effect was observed following incubation with fluorescein isothiocyanate (FITC)-inactivated Ep . These findings are discussed and possible role of cAMP as the intracellular messenger for Ep action is suggested.

J Endocrinol, 1979 Jan, 80(1), 41 - 50
Inhibition of aldosterone production in adrenal cell suspensions by serum from patients with manic-depressive psychosis; O'Brien MJ et al.; A method of preparing a suspension of cells of the zona glomerulosa from rat adrenal capsules treated with crude collagenase is described . The cells responded to ACTH, angiotensin II and serotonin by increased production of aldosterone . Pooled human sera or individual human sera (from healthy normal or non-psychiatric in-patients) to a final concentration of 30% had no effect on ACTH-stimulated production of aldosterone . Many serum samples from five patients with manic-depressive psychosis, however, caused a reduction in aldosterone production; 65% of those samples taken during depression, 44% of the samples taken during manic episodes and 23% of the samples taken when the mood was normal . Sera from manic-depressive patients also reduced the production of aldosterone caused by angiotensin II or serotonin . This effect of serum from manic-depressives in vitro may be related to the abnormalities of aldosterone control in such patients.

Anat Rec, 1979 Jan, 193(1), 23 - 41
Characterization of Sertoli cell-germ cell junctional specializations in dissociated testicular cells; Romrell LJ et al.; To further characterize Sertoli cell-germ cell junctional specializations seminiferous tubules from sexually mature Sprague-Dawley rats were dissociated by enzymatic and mechanical methods . Ultrastructural analysis of cell suspensions prepared by incubation in collagenase alone or by mechanical methods revealed that spermatids remained attached to Sertoli cells or Sertoli cell fragments . Such cellular associations were found only between Sertoli cell fragments and spematids in which the developing acrosome had made contact with the plasma membrane (step 8 and subsequent steps of spermiogenesis) . Furthermore, the fragments were confined to that region of the plasma membrane over the acrosome . The Sertoli cell half of this adhesive site displayed the typical elements of Sertoli cell junctions, filamentous bundles and associated cisterna of endoplasmic reticulum, in apposition to the spermatids . The spermatids demonstrated no surface specializations at the attachment sites . In contrast, in cell suspensions prepared with trypsin, spermatids were free of attachments to Sertoli cells or their fragments . These results demonstrate that: (1) the junctions act to bind cells together, (2) adhesive type contact is established between Sertoli cells and spermatids at step 8 and subsequent steps of spermiogenesis, (3) contact is restricted to the spermatid plasma membrane over the acrosome, and (4) spermatids can be freed from the junctional specializations by treatment with trypsin.

Scand J Immunol, 1979, 10(3), 241 - 9
Lymphocyte subpopulations in man: B-cell stimulation induced by pokeweed mitogen and irradiated T cells; Johnsen HE et al.; The enhanced stimulation of human B lymphocytes by pokeweed mitogen in the presence of irradiated T helper lymphocytes has been studied, revealing that the proliferative responses measured by incorporation of thymidine in cultures of B lymphocytes and irradiated T lymphocytes in a 1:2 or 1:4 ratio is mostly a function of the B cells . Only a minimal number, if any, of the T cells contaminating the B cell suspensions is stimulated to proliferation . This is in contrast to stimulation of the B-cell suspensions without addition of irradiated T cells, where both B cells and T cells proliferate . The irradiated T helper cells have no FcR for antigen-bound IgG, and as well allogeneic as autologous T cells exhibit helper capacity of equal strength . The test system described makes it possible selectively to test one B-cell function and the corresponding T helper capacity.

C R Seances Soc Biol Fil, 1979, 173(2), 282 - 7
{Cell mediated cytolysis: identification, enumeration and characterization of killer cells}; Zagury D; Killer cells responsible of the cell mediated cytolysis are identified by a microtechnique: effector cells are individually associated to target cells and incubated at 37 degrees C; killers are identified by their associated target lysis . Thus killer cells are enumerated in the effector cell suspensions . Furthermore, isolated killer can be characterized and their lethal action studied.

J Immunol Methods, 1979, 28(3-4), 381 - 90
Detection of early lymphocyte activation by the fluorescent cell membrane probe N-phenyl-1-naphthylamine; Halliday GM et al.; N-phenyl-1-naphthylamine (NPN) becomes fluorescent after binding to hydrophobic regions of cell membranes . Rat and mouse lymphoid cell suspensions stained with NPN showed changes in fluorescence emission 30 min after stimulation with mitogen or antigen, detected by microfluorimetry . Incubation of NPN-labelled mouse and rat thymocytes with phytohaemagglutinin or concanavalin A (Con A) caused an increase in mean cell fluorescence intensity . The response to Con A was inhibited by sodium azide and alpha-methyl mannoside . Stimulation of spleen cells from mice by allogeneic cells, or from tumour-bearing rats by tumour antigen consistently resulted in decreased fluorescence . The 'mixed lymphocyte response' detected only certain genetic differences between mouse strains and was proportional to the ratio of stimulator to responder cell number . The NPN staining procedure offers a simple and rapid assay of immunoreactivity and a means of studying early subcellular changes following lymphocyte activation.

Acta Haematol, 1979, 62(5-6), 306 - 14
Humoral factors modulating growth of granulocyte macorphage progenitor cells; Havemann K et al.; The kinetic of production of colony-stimulating activity (CSA) inducing mouse and human colony-forming cells (CFU-C) was tested in different human leukocyte culture systems . Stimulated and unstimulated cultures of spleen single cell suspensions, peripheral mononuclear leukocytes and acute monocytic leukemia (AMoL) cells were investigated . With the exception of the AMoL cells, stimulated cultures always revealed higher CSA levels than unstimulated controls . The spleen cell cultures exhibited the highest overall activity showing three molecular species of 70,000, 35,000 and 10,000 daltons activating human CFU-C to form colonies in the agar culture system . Furthermore it could be demonstrated that colony formation could be inhibited by low molecular weight fibrinogen degradation products obtained by digestion of fibrinogen with granulocyte-derived elastase.

Z Allg Mikrobiol, 1979, 19(3), 155 - 62
{Effect of tridemorph on Torulopsis candida Berlese}; Bergmann H; From the results of application of various inhibitors, or combinations of inhibitors to cell suspensions of the yeast Torulopsis candida and by determination of O2-consumption and growth rates it is concluded, that a main site of action of tridemorph is localized in the pathway of the respiratory chain . Tridemorph inhibits as well the respiration as the growth of T . candida depending on the concentration and the time of exposition . Tridemorph does not uncouple respiration but inhibits the uncoupled respiration to the same extent . Inhibition of respiration and growth by tridemorph is enhanced by suboptimal concentrations of antimycin A, oligomycin, rotenone, and 2,4-dinitrophenole . That leads to the conclusion that these inhibitors essentially enlarge the permeability for tridemorph which can be more rapidly transported to the site of action.

Acta Histochem, 1979, 64(2), 139 - 47
Lymphocyte activation and the increase of nuclear birefringence; Surjan L Jr et al.; Nuclear birefringence of neutral red or rivanol stained cell suspensions from rat spleen has been investigated . Polyclonal or monoclonal mitogens produced an increased birefringence of the nucleus following 30 min in vitro stimulation at 37 degrees C . The nuclear birefringence increased by 62.2% {p less than 0.001}, when the cells were incubated in the supernatants of a previously phytohemaglutinin stimulated culture . Amantadine, a potent phytohemagglutinin inhibitor, was unable to prevent the effect of the supernatant, but heating for 1 h at 56 degrees C destroyed its activity . The results suggest that increase in nuclear birefringence is mediated by a soluble factor which is released in the course of lymphocyte activation . The nuclear birefringence of surviving cells from human spleens obtained within 6 to 24 h post mortem increases after in vitro stimulation.

J Immunol Methods, 1979, 29(1), 17 - 25
Pretreatment of plastic Petri dishes with fetal calf serum . A simple method for macrophage isolation; Kumagai K et al.; We have developed a simple method which can recover the highly purified macrophages or monocytes in suspension from mouse peritoneal exudate cells and human perpheral blood mononuclear cells . Plastic Petri dishes coated overnight with heat-inactivated fetal calf serum (FCS) selectively bind macrophages and monocytes . The adherent macrophages and monocytes are easily removed by incubation in phosphate-buffered saline containing 0.2% ethylenediamine tetraacetate (EDTA) and 5% FCS, and recovered as a cell suspension with greater than 95% purity . A small number of isolated cells can restore the mitogenic response to phytohemagglutinin (PHA-P) of macrophages-depleted lymphocytes and can lyse 51Cr-labeled target cells in an antibody-dependent cell-mediated cytotoxicity system . Thus, the method should be valuable for studies of various functions of macrophages and monocytes from different immune tissues of man and animals.

Acta Derm Venereol, 1979, 59(3), 201 - 4
Studies on Fc-receptor-bearing mononuclear leukocytes from peripheral blood of patients with dermatitis herpetiformis; Thorsteinsson L et al.; Isopaque-Ficoll separated mononuclear cell suspensions from peripheral blood of patients with dermatitis herpetiformis (DH) and healthy controls were investigated by means of a rosette assay for Fc-receptor-bearing leukocytes (EA-RFC), peroxidase staining for monocytes (Pox) and a plaque formation assay (PFC) as well as a 51Cr release assay for cell-mediated cytotoxicity . The cell suspensions were investigated both before and after fractionation on nylon fibre columns . In the patients the mean percentage of PFC in unfractionated cell suspensions was significantly higher than in the controls . In fractionated cell suspensions both the mean percentage of EA-RFC and the mean cytotoxicity index in the 51Cr release assay were significantly lower than in the controls . There were no differences in the percentages of PFC- and Pox-positive cells in fractionated cell suspensions . The results suggest a numerical defect of circulating Fc-receptor-bearing lymphocytes as estimated both by the rosette assay and the 51Cr release assay . These data may reflect a pathogenetic role of these lymphocytes in DH.

Arch Androl, 1979, 3(2), 127 - 33
Study of the effects of neurotransmitters on the hypothalamus-pituitary-testis function in in vitro cell suspension system; Vermes I et al.; The effects of different neurotransmitters were tested in vitro on a hypothalamic tissue, collagenase-digested isolated anterior pituitary and Leydig cell suspension system by measuring the testosterone production of the Leydig cells . Neurotransmitters were used in concentrations of 0.25, 1.0, 2.5, 5.0, and 10.0 micrograms/ml incubation medium . Dopamine in doses of 1.0, 2.5, and 5.0 micrograms/ml increased the hypothalamic tissue-induced pituitary-testis activation, while it had no direct effect on pituitary and Leydig cells . Noradrenaline in the concentration range 2.5--10.0 micrograms/ml decreased the luteinizing-hormone-releasing-hormone (LHRH) sensitivity of the pituitary cells . 5.0 and 10.0 micrograms/ml 5-hydroxytryptamine decreased the testosterone production and the hCG sensitivity of the isolated Leydig cells . Carbamylcholine and pilocarpine had no action on the in vitro system at the different levels studied.

Vet Med Nauki, 1979, 16(1), 18 - 22
{Dynamics of multiplication of BHK21C13 cells in a suspension}; Tivchev G et al.; In order to master a new method for the production of a F . M . D . vaccine the authors have studied the reproduction dynamics of BHK21C13 cells in the conditions of a suspension culture . The culturing of the cells has been carried out under laboratory conditions, investigating also the concurrent changes in the pH value along with the cell dynamics . The nutrient medium used and the conditions of cultivation has made it possible to study the properties and obtain a qualitative cell suspension . The cells obtained have shown equally good growth in a monolayer medium and in a suspension, and are appropriate for the reproduction of the F . M . D . virus.

Folia Biol (Praha), 1979, 25(4), 231 - 41
Functional differentiation of mouse T lymphocytes . GVHR-precursors: tissue origin and specificity of activity inducer; Draber P et al.; For theoretical and practical reasons, it is important to find out whether the differentiation of T cell precursors to the functional lymphocytes can be induced under in vitro conditions . Using the local GVHR assay (based on the enlargement of the popliteal lymph node), the inducibility of the precursors of reactive cells was studied with bone marrow, thymus, spleen, and lymph node cell suspensions submitted to short-term incubation with cell-free extracts from calf thymus, spleen or brain . GVHR-precursors from bone marrow were inducible not only specifically (i.e., with thymus extract) but also--and even to a higher degree--with spleen or brain extract . Thymus and spleen cell suspensions (the latter also depleted of the reactive subpopulation by treatment with anti-Thy 1.2 serum and complement) were, on the other hand, inducible mainly specifically, whereas lymph node cells were refractory to induction . The inductive action of tissue extracts obviously depends on the tissue origin of T cell precursors; their effects on pre- and postthymic differentiation of T lymphocytes are discussed.

Monogr Endocrinol, 1979, 12, 219 - 41
Multihormonal control of tyrosine aminotransferase in isolated liver cells; Ernest MJ et al.; The regulation of tyrosine aminotransferase activity by glucocorticoids and cyclic AMP was investigated in isolated liver parenchymal cell suspensions . The induction and maintenance of elevated levels of tyrosine aminotransferase activity in liver cells were completely dependent upon the presence of both the synthetic glucocorticoid, dexamethasone, and glucagon of dibutyryl cyclic AMP . No induction was observed when any of these compounds were tested alone . Immunotitration experiments revealed that the 6- to 7-fold increase in tyrosine aminotransferase activity following the addition of dexamethasone and glucagon was accompanied by a parallel increase in the amount of immunologically reactive enzyme protein . Pulse-labeling experiments established that this increase in enzyme protein could be fully accounted for by a corresponding increase in rate of synthesis of tyrosine aminotransferase . Neither hormone had any effect on the rate of degradation of the enzyme . The increase in tyrosine aminotransferase synthesis evoked by the presence of both hormones was blocked by the addition of actinomycin D or cycloheximide to the medium, demonstrating that RNA and protein synthesis were required for the induction of enzyme activity . By varying the time and order of addition of the inducers and inhibitions, evidence was obtained that the hormones act sequentially . The steroid hormone acts first, presumably to increase the level of functional tyrosine aminotransferase mRNA or its precursor . The processing of this precursor to a translatable form or the specific translation of tyrosine aminotransferase mRNA is apparently dependent upon a specific cyclic AMP-controlled process . In vivo experiments demonstrated that both glucocorticoids and cyclic AMP increase the level of functional tyrosine aminotransferase mRNA in the liver . The actions of the steroid hormone and cyclic nucleotide were blocked by alpha amanitin, establishing the requirement for ongoing gene transcription . The protein synthesis inhibitors, cycloheximide, emetine, and puromycin, were as effective as cyclic AMP in increasing tyrosine aminotransferase mRNA activity . The action of these inhibitors is probably related to their ability to elevate hepatic intracellular cyclic AMP levels, thus mimicking cyclic AMP administration . Extension of these in vivo studies to isolated liver cells will provide a valuable system for investigating the regulation of gene expression by glucocorticoids and cyclic AMP.

J Histochem Cytochem, 1979 Jan, 27(1), 114 - 9
Flow microfluorometric identification of liver cells with elevated gamma-glutamyltranspeptidase activity after carcinogen exposure; Vanderlaan M et al.; We have developed a fluorometric cytochemical assay for gamma-glutamyltranspeptidase (gamma-GT) using the substrate gamma-glutamyl-4-methoxy-2-naphthylamide in which the released methoxynaphthylamine was coupled with 5-nitrosalicylaldehyde to form a yellow fluorescent crystalline product within the cells . Single cell suspensions were obtained by collagenase perfusion of livers from rats that had either received a two-thirds partial hepatectomy followed 24 hr later by a single injection of diethylnitrosamine (DEN) or received a partial hepatectomy alone . Cultured HTC cells were used as a source of gamma-GT+ cells . Fluorescence (gamma-GT activity) was low in most of the cells from both DEN-exposed and control rats, but high in HTC cells . The livers of both DEN-exposed and control rats had a subpopulation of cells that were gamma-GT+; this population could be quantitated and sorted by flow cytometry . Five weeks post injection the number of GT+ cells from the rats exposed to DEN was more than 20 times that from the control rats . Increased gamma-GT activity may be a useful cytochemical marker for preneoplastic liver cells.

Biochim Biophys Acta, 1978 Dec 19, 514(2), 213 - 24
Inhibition of membrane fusion by suppression of lateral movement of membrane proteins; Volsky DJ et al.; Chicken erythrocytes were fused either by Sendai virus or by the combination of Ca2+ and ionophore A23187 . Intramembrane particles and external anionic sites of cells undergoing fusion were found to acquire the ability to undergo a process of cold-induced clustering (thermotropic separation) . Cationized ferritin (200 microgram/ml 5% (v/v) cell suspension) inhibited both the fusion process and the thermotropic separation of intramembrane particles and external anionic sites . The correlation between the mobility of membrane proteins and the fusion process is discussed . It is suggest that an increase in the lateral mobility of membrane proteins is a prerequisite for initiation of membrane fusion.

Teratology, 1978 Dec, 18(3), 367 - 78
Effect of maternally administered sodium nitrite on hepatic erythropoiesis in fetal CD-1 mice; Globus M et al.; A commonly used food preservative, sodium nitrite, was administered to pregnant CD-1 mice at a concentration of 0.5 mg/mouse/day . Embryotoxic and teratogenic effects on the hemopoietic tissues and skeletons of their offspring, were evaluated . Fetal mortality, resorptions, the mean number of offspring per litter, the mean weight per embryo and the incidence of skeletal malformations, were not significantly different from controls . Hemopoietic cell suspensions, prepared from the livers of treated and control 14-, 16- and 18-day embryos, were cytocentrifuged onto microscope slides and differential counts were performed after staining with benzidine and Wright-Giemsa stain . The results indicate that maternally administered Na nitrite, stimulates fetal hepatic erythropoiesis . This was manifested in a statistically significant increase in the percentage of polychromatophilic erythroblasts and mature erythrocytes at 14 and 16 days of gestation, respectively . The possibility that Na nitrite may induce fetal methemoglobinemia is discussed and mechanisms responsible for the observed erythroid stimulation, are considered.

Immunology, 1978 Dec, 35(6), 917 - 22
Growth characteristics of PHA-induced colonies in primary and secondary agar culture; Goube de Laforest P et al.; PHA-induced colonies were obtained from peripheral blood mononuclear cells (MC) grown in agar-medium . When the colonies were harvested from mass cultures, pooled as single cell suspensions and plated again in presence of PHA, they failed to generate new colonies unless they were seeded on an underlayer containing uncultured blood MC . Cytogenetic studies indicate that most secondary colonies were derived from primary colonies . Autologous as well as heterologous feeder cells were able to promote the growth of secondary colonies . No granulocyte (G) or macrophage (M) colony formation was observed in secondary cultures . These experiments show that the progenitors of PHA-induced colonies differ from G or M CFCs and that they are still detected in these colonies which contain 82 +/- 12% T-cells . In contrast, colony formation requires the presence of factor(s) provided by cooperating cells (CC) which are no longer detected in primary colonies and this is associated with a depletion in non-T elements from the initial MC population.

Blood, 1978 Dec, 52(6), 1189 - 95
Measurement of sickling by controlled temperature increase; Chang H et al.; Previous experiments to study the rate of red cell sickling have employed rapid mixing apparatus for SS cells with dithionite and have shown that the half-time of sickling is quite rapid, on the order of seconds . An alternative approach is to slow down the rate by taking advantage of the negative temperature coefficient of the process . We developed a method in which deoxygenation of a cell suspension is carried out at 0 degrees C . A linear temperature gradient to 37 degrees C is applied, and a gradual increase in the percentage of sickled cells is observed . At a heating rate of 1.5 degrees C/min the temperature at which half of the cells became sickled was 19 degrees C for SS cells treated with dithionite, 22 degrees C for SC cells, 28 degrees C for AS cells, 22 degrees C for cyanate-treated SS cells, and 23 degrees C for SS cells in the presence of 0.1 M butylurea . Thus this method promises to be useful for the study of sickling rates and the screening of potential anti-sickling agents.

J Anat, 1978 Dec, 127(3), 553 - 61
Surface features of exfoliated vaginal epithelial cells during the oestrous cycle of the rat examined by scanning electron microscopy; Centola GM; The purpose of this study was to document vaginal exfoliative cytology (smears) as seen with the scanning electron microscope during the first, hormonally induced oestrous cycle of PMS-LH treated immature rats and to compare it with the surface morphology of the intact vaginal wall of similarly treated rats . Exfoliated cells were obtained by vaginal lavage 7--9 hours (pro-oestrus), 18--20 hours (oestrus), 28--34 hours (metoestrus) and 60--64 hours (dioestrus) after administration of luteinizing hormone . Cell suspensions were plated upon moistened Millipore filters according to the method of Shelton & Orenstein (1975) . The pro-oestrous stage was characterized by round to ovoid cells with numerous short microvillus-like protrusions and blebs . The vaginal wall exhibited folds lined by cells with many short microvilli . Oestrus was characterized by flattened angular cells with either blebs, microridges or both . The intact wall exhibited 'flattened mosaics' of cells, some in the process of desquamation, with ridges and pits . Metoestrus resembled oestrus, except for the presence of a few leucocytes in the plated specimens . Dioestrus was characterized by an abundance of pleomorphic leucocytes with blebs of varying sizes . The vaginal wall appeared as a 'cobblestone' pavement with cells of varying sizes and shapes possessing numerous short, microvilli with bulbous endings.

Mol Gen Genet, 1978 Nov 16, 167(1), 1 - 9
Murein-lipoprotein of Escherichia coli: a protein involved in the stabilization of bacterial cell envelope; Suzuki H et al.; Two independent mutants of Escherichia coli lacking murein-lipoprotein have been found . One mutant whose mutation was named lpo was subjected to detailed analyses . The absence of both bound and unbound lipoproteins was shown by electrophoretic analysis of 14C-arginine labelled membrane proteins of the mutant . Nor was serologically cross-reacting material detected in the mutant by the Ouchterlony-method . Sequestering magnesium from mutant cell suspensions by ethylenediaminetetraacetic acid caused cell lysis, which was prevented in the presence of 0.5 M sucrose . Incubation in culture media at a very low level of magnesium resulted in the formation of blebs in the mutant . Examination of mutant cells by electron microscopy showed that the outer membrane of the mutant was uneven with small irregular protuberances, some of which pinched off forming vesicles of various sizes . Phosphotungstate used for negative-staining penetrated into the periplasmic space of the mutant cells . The mutants leaked a considerable fraction of their periplasmic enzymes . These physiological and morphological alterations in the lipoproteinless mutant suggest that murein-lipoprotein helps to maintain the outer envelope structure by connecting the outer membrane with murein so that the outer membrane may fulfil its physiological functions as a barrier to the environment.

Isr J Med Sci, 1978 Nov, 14(11), 1157 - 61
Cell separation, cell differential and granulocyte colony frequency in polycythemia vera; Astaldi G et al.; In seven patients with polycythemia vera, the agar colony growth of bone marrow total nucleated cell suspensions and of the cell fractions obtained with an albumin discontinuous density gradient were studied . In one patient, the density distribution of colony-forming units in culture (CFUc) before and after alkylating treatment was evaluated and cell differentials on smears obtained from each density fraction were determined . A high percentage of low density CFUc compared with the total CFUc population and with that in the normal control subjects in the same density fractions was observed.

Naunyn Schmiedebergs Arch Pharmacol, 1978 Nov, 305(2), 173 - 80
Metabolism of phenacetin and N-hydroxyphenacetin in isolated rat hepatocytes; McLean S; The fate of phenacetin and some of tis metabolites have been examined in isolated rat hepatocytes . The overall pattern of metabolism was similar to that found in vivo by others . The major metabolites of phenacetin were paracetamol, free and conjugated, and phenetidine, and about 10% was lost . No N-hydroxyphenacetin was found, but experiments with N-hydroxyphenacetin as substrate showed that at low concentration (as might be formed from phenacetin) it disappeared very rapidly from cell suspensions . N-hydroxyphenacetin was metabolized to its conjugates, and to paracetamol, phenacetin and phenetidine, with a large proportion unaccounted for . With all substrates, increasing concentration resulted in a decreased percentage being metabolized, indicating that the metabolic pathways were saturable . Relatively more phenetidine was found at high phenacetin concentrations, however, apparently because phenetidine is an intermediate metabolite whose own elimination was slowed relatively more than its formation . N-hydroxylated arylamines were toxic to hepatocytes in a dose-dependent manner, suggesting that these cell suspensions could be used to test for hepatotoxicity.

J Lipid Res, 1978 Nov, 19(8), 1068 - 70
Procedure for determination of free and total cholesterol in micro- or nanogram amounts suitable for studies with cultured cells; Gamble W et al.; Procedures for the determination of free and total cholesterol in lipid extracts or sonicates of 10(4) cultured human skin fibroblasts are described . The method for free cholesterol employs cholesterol oxidase to generate H2O2 and peroxidase to catalyze the reaction of H2O2 with p-hydroxyphenylacetic acid to yield a stable fluorescent product . Cholesterol ester hydrolase is included for determination of total cholesterol . When samples of sonified cell suspensions are used directly, the extraction of lipids is avoided, permitting one person to carry out analyses of 30 or more subcultures in one day.

Cancer Res, 1978 Nov, 38(11 Pt 2), 4050 - 3
Effect of parity on recovery of inapparent nodule-transformed mammary gland cells in vivo; DeOme KB et al.; Inapparent nodule-transformed cells were recovered from five late-pregnant, first-pregnancy BALB/cfC3H females 4 months of age and from five late-pregnant multiparous females 6 to 7 months of age . Mammary tissues were removed from each donor and dissociated by means of the enzyme collagenase (0.1%), hyaluronidase (0.1%), and pronase (1.25%) . Aliquots of 100,000 viable cells in 0.01 ml of media were injected into the gland-free mammary fat pads of 3-week-old syngeneic host mice . Ten weeks after the injection the outgrowths were classified as ductal, nodule, tumor, or combinations of these types of outgrowths . The recovery of nodule outgrowths indicated the presence of nodule-transformed cells in the cell suspension that was injected . All donors yielded nodule outgrowths, and the percentage of outgrowths was significantly greater than was the percentage recovered from virgin BALB/cfC3H females of the same age groups . The latent period for the emergence of nodules and tumors was reduced from 8 to 9 months in virgin females to 4 months in parous females . The incidence of both nodules and tumors was greatly increased . The data suggest that parity significantly increases the numbers of nodule-transformed cells in donor tissue, decreases the time required for the emergence of nodules and tumors, and increases the number of overt nodules and tumors.

Ann Neurol, 1978 Nov, 4(5), 431 - 9
Characterization of antioligodendrocyte serum; Traugott U et al.; An antioligodendrocyte serum (AOS) has been raised in rabbits against preparations of isolated bovine oligodendrocytes . The antibody was assayed by two techniques . By complement fixation with isolated oligodendrocytes, the titer of the antibody was 1:64 to 1:128 . By indirect immunofluorescence testing of oligodendrocyte suspensions and frozen brain sections, the titer of the AOS was 1:256 to 1:512 . When unabsorbed AOS was used, immunofluorescent staining proved it specific for bovine oligodendrocytes in suspension and in sections, and for human oligodendrocytes in sections . In cell suspensions, the staining was membrane related and in sections, cytoplasmic . The oligodendrocyte staining could be totally removed by absorption of AOS against oligodendrocyte suspensions, whereas absorption against bovine myelin, bovine myelin basic protein, and bovine neurons did not affect the staining reaction . AOS also stsined Schwann cells, a property possible related to antigens shared with oligodendrocytes . It is concluded that AOS is specific for oligodendrocytes and can now be applied to fundamental and disease-rel

J Infect Dis, 1978 Nov, 138(5), 605 - 13
Significance of thymus-derived lymphocytes in immunity elicited by immunization with ribosomes or live yeast cells of Histoplasma capsulatum; Tewari RP et al.; The lymphoid cells responsible for protective immunity to histoplasmosis were characterized . Adoptive transfer of spleen and peritoneal cells treated with antiserum to theta-antigen from mice immunized with ribosomes or live yeast cells of Histoplasma capsulatum abrogated the ability of these cells to protect the syngeneic recipients, whereas treatment of lymphoid cells with antiserum to IgG did not affect the immunity . Prior removal of glass-adhering cells from spleen and peritoneal cell suspensions did not alter their protective activity . Treatment with mitomycin C, an antimitotic agent, ablated the capacity of immune lymphocytes to protect the syngeneic recipients . These results indicate that the immune spleen and peritoneal cells that confer immunity to histoplasmosis are thymus-dependent (T) lymphocytes and that their active proliferation in the recipients is necessary for expression of the protective immunity . Furthermore, the immunity elicited by immunization with histoplasma ribosomes and live yeast cells is mediated by a similar mechanism.

J Immunol, 1978 Nov, 121(5), 2056 - 9
Types of cells involved in antigen-stimulated and spontaneous rosette formation with Toxoplasma gondii; Masihi KN et al.; Antigen-binding cells were identified by using rosette formation of Toxoplasma gondii and defined lymphoid populations under different experimental conditions . Treatment of immunized spleen cell suspensions with anti-Thy 1 serum plus complement inhibited 5 to 29% of the rosette-forming cells (RFC) . Higher numbers of thymus-derived lymphocyte-RFC were obtained after incubation at 4 degrees C and by the centrifugation method than by simple incubation at 20 degrees C . RFC were also observed with thymocytes . Combined treatment with anti-Thy 1 serum plus complement and depletion of adherent cells indicated that the major proportion, 46 to 70%, of RFC were B cells . Spleenocytes of nu/nu mice formed similarly high numbers of rosettes . Spontaneous RFC were observed in nonimmunized mice with both spleen and thymus populations . Numbers of rosettes varied considerably depending on the method and the source of cell population used . Removal of adherent cells from spleen suspensions resulted in RFC reduction of 14 to 25% in immunized and 14 to 33% in nonimmunized animals . Pretreatment with anti-mouse immunoglobulin inhibited completely the spleen and spontaneous thymus RFC and partially the thymus RFC in immunized animals.

J Bacteriol, 1978 Nov, 136(2), 765 - 74
Physiological and morphological observations on Thiovulum sp; Wirsen CO et al.; Cell suspensions of Thiovulum sp., collected from enrichment cultures, were grown, maintained, and harvested for periods up to 7 months . In open-flow cultures run with aerated seawater, a continuous supply of hydrogen sulfide was provided by diffusion through a semipermeable membrane from either a live culture of Desulfovibrio esturaii, neutralized sodium sulfide, or a N2-H2S gas mixture . Attempts to grow Thiovulum in pure culture failed despite variation in concentrations of dissolved oxygen and hydrogen sulfide in stratified as well as in completely mixed systems . Uptake of 14CO2 and some organic compounds by purified cell suspensions was measured, and values were corrected for the activity of heterotrophic as well as autotrophic contaminants as determined in control experiments . Cell populations exhibited maximum uptake activities during formation of the characteristic veils . Substantial uptake of CO2 in air-saturated seawater was coincident with an optimal concentration of hydrogen sulfide of about 1 mM . Glutamate and a selection of vitamins (B12M biotin, and thiamine) did not significantly affect the uptake of CO2 . No substantial uptake of carbon from acetate, glutamate, mannitol, and Casamino Acids was found . Within the range of error indicated, the data are consistent with acceptance of a chemolithotrophic nature of Thiovulum.

Biol Bull Acad Sci USSR, 1978 Nov-Dec, 5(6), 744 - 7
Conditions for the appearance of adifferentiated nocardioform variants of Streptomyces roseoflavus var . roseofungini; Salekh S et al.; It was shown that adifferentiated nocardioform variants (NV) of Streptomyces roseoflavus var . roseofungini 1128 may appear in mycelial cell suspensions of submerged actinomycete cultures in water, phosphate buffer, and water with fructose (1%) or glucose (1%), as well as in mycelia of old (10-30 days) cultures on different carbon sources . When sugars, alcohols, or amino acids were added to a medium with fructose, NV formation was inhibited, but not completely suppressed . Fructose was shown to be the most potent factor in the appearance of NV.

Am J Physiol, 1978 Nov, 235(5), C269 - 78
Influence of pH on elastic deformability of the human erythrocyte membrane; Crandall ED et al.; Fresh human blood was diluted 1:5000 in buffered saline-sucrose solution and titrated to a pH varying from 4.5 to 10.5 with 0.1 N HCl or 0.1 N NaOH . Circular regions of the membrane of individual cells were then deformed at 25 degrees C by aspiration into a micropipette having an internal tip diameter of 0.9-1.4 micron . A membrane surface elasticity modulus, mu (dyn/cm), was computed from the relationship between length of the aspirated membrane and the deforming pressure according to a two-dimensional membrane model . Surface elasticity increases with decreasing pH and with time after the cell suspension is acidified, rising several orders of magnitude with a t1/2 of 1--5 h as pH is lowered from 7.2 to 4.6 . This increase in mu is only partially reversible . pH greater than 7.2 had little effect on mu . Membrane surface elasticity is not affected by variations in external {Ca2+} over the range of 0--50 mM, tonicity of the suspension medium from 275--400 mosM, or age of 0--50 h . Addition of 50 mM NaHCO3 to the medium increases the rate of change of mu at a given pH . These results suggest that the elastic properties of the red cell membrane are largely determined by interactions among structural proteins located on the cytoplasmic surface of the membrane and that these interactions are initiated by changes in intracellular pH.

Eur J Pediatr, 1978 Oct 12, 129(3), 197 - 204
Fetal blood-borne myelo- and thrombopoietic stem cells in diffusion chambers; Prindull G et al.; The potential of hematopoietic stem cells from cord blood for proliferation and differentiation have been studied by the diffusion chamber technique . In a pilot study, it was shown that blast cell production and myelopoiesis from the original lymphoid cell suspension starts 6 days after implantation . Mature granulocytes and megakaryocytes respectively appear in the chambers from the 16th and 10th days onwards . Myelopoiesis is ten times more active in fetal than in adult blood . There were thrombopoietic stem cells in 7 of 10 cord blood samples but in only one of 10 adult blood specimens . It is concluded that the high hematopoietic activity of the bone marrow at term is reflected by an increase in the number of stem cells circulating in the blood . Myelo- and thrombopoietic stem cells must be sought among the lymphoid cells of the original cord blood cell suspension.

Biokhimiia, 1978 Oct, 43(10), 1805 - 8
{Relationship between the ganglioside composition of Ehrlich ascitic carcinoma and cell population density}; Prokazova NV et al.; The ganglioside composition of Ehrlich ascite carcinoma cells changes drastically with changes in density of the cell population . Upon 30-fold dilution of the native cell suspension and subsequent incubation for 2 h the amount of total gangliosides per cell doubles the quantities of a monosialoganglioside and of a disialoganglioside increase ten- and five-fold, respectively, whereas the other cell gangliosides do not change . The decrease of cell density is supposed to be accompanied by induction on the cell surface of a sialytransferase activity, which appears to be depressed in the dense suspension.

Clin Sci Mol Med, 1978 Oct, 55(4), 413 - 5
Tracing the fate of oxygen consumed during phagocytosis by human neutrophils with 15O2; Segal AW et al.; 1 . The metabolism of oxygen by phagocytosing neutrophils was traced by using 15O2 . 2 . The isotope did not exchange with the incubation medium or cells to an appreciable extent and unmetabolized oxygen was readily eluted by gassing the cell suspension . 3 . The polarographic measurements of oxygen consumption closely paralleled the recovery of metabolized 15O2 . 4 . Almost all the metabolized 15O2 was converted into water, both in the presence and absence of KCN, supporting the concept that the oxygen consumed by neutrophils is converted into H2O2 . It is unlikely that an appreciable proportion of this oxygen is incorporated into the organic composition of the cell or of the ingested micro-organism.

J Cell Biol, 1978 Oct, 79(1), 1 - 9
The effects of temperature and glucose on protein biosynthesis by immature (round) spermatids from rat testes; Nakamura M et al.; A method is described for the preparation of highly purified fractions (greater than 80% pure) of immature spermatids (round, steps 1--8) from rat testes by centrifugal elutriation in sufficient yields for biochemical studies when four rat testes are used . Electron microscopy established the identity of the cells and demonstrated that the cell membrane is intact . Some cells develop nuclear and cytoplasmic vacuoles during the 2 h required for preparation . Immature spermatids prepared by this method use glucose with an increase in oxygen consumption, lactate production, and protein synthesis over control levels (no glucose) . The testicular cell suspension from which spermatids are separated, like whole testis and spermatids themselves, show higher incorporation of amino acids into TCA-precipitable material at 34 degrees C than at 38 degrees C and in the presence of glucose . A subcellular system prepared from immature spermatids with excess ATP shows greater incorporation of amino acids into TCA-precipitable material at 34 degrees C than at 38 degrees C . This difference does not result from increased breakdown of protein . It is concluded that body temperature (38 degrees C) inhibits some aspect(s) of protein synthesis in addition to previously reported effects on amino acid transport and production of ATP (Means and Hall . 1969 . Endocrinology . 84:285--297.).

Aust J Exp Biol Med Sci, 1978 Oct, 56(5), 571 - 7
Transfer of mouse IgG2 production by IgM-bearing spleen cells separated by a fluorescence-activated cell sorter; Bankhurst AD et al.; The purpose of the present study was to determine whether at least some splenic B lymphocytes can switch from the synthesis of one isotype of immunoglobulin to another during B cell differentiation . The experimental system invovled the transfer of characterized cell suspensions between allotype congenic strains of mice followed by analysis in the recipient for donor type immunoglobulin production . Donor splenic lymphocytes were incubated with specific fluorescent labelled anti-mu antiserum and passed through the Los Alamos fluorescence-activated cell sorter; mu-depleted cell suspensions were transferred into sublethally irradiated congenic recipients and the amount of donor type immunoglobulin of IgG2 type was measured at weekly intervals . The results demonstrated taht at least some cell bearing membrane bound IgM can differentiate in vivo into IgG2-secreting cells, although not all IgG2-secreting cells have been recently derived from IgM positive precursors.

Gut, 1978 Oct, 19(10), 898 - 906
Preparation of lymphoid cells from small specimens of human gastrointestinal mucosa; Crofton RW et al.; Several methods for the preparation of cell suspensions from human gastrointestinal mucosa were investigated . Satisfactory suspensions were obtained by incubating tissue fragments in a solution of collagenase and hyaluronidase overnight at 4 degrees C followed by 30 minutes at 37 degrees C . The resulting suspension contained large numbers of intact lymphoid cells; in addition, variable amounts of epithelial cells and cell debris were present . A high proportion of the lymphoid cells were shown by immunofluorescence to contain immunoglobulin (mainly IgA) . Viability of these cells was demonstrated by dye exclusion, their ability to survive in short-term culture, and their ability to incorporate radio-labelled amino acid into immunoglobulin in vitro.

Endocrinology, 1978 Oct, 103(4), 1173 - 82
Progressive suppression of adrenocorticotropin secretion in resting adrenalectomized dogs by low stepwise infusions of cortisol; Cowan JS et al.; Ten male mongrel dogs of 8.3-14.3 kg were bilaterally adrenalectomized and maintained on replacement steroids for 1 week . No exogenous steroids were detectable at the time of the experiment . Each dog, under light Nembutal anesthesia, received two stepwise primed constant infusions of cortisol (iv), each lasting 90 min (except in one dog with three infusions of 60 min) . A recovery period of 80 min without cortisol infusion followed . Twenty-three venous blood samples were withdrawn for determination of plasma ACTH by adrenal cell suspension bioassay and 25 were withdrawn for plasma cortisol by fluorimetry at various times before, during, and after the cortisol infusions . ACTH secretion rates were calculated continuously from functions fitted to ACTH concentration and time data, using a validated single compartment approach with previously determined clearances and volumes . Initial high ACTH secretion rates of 1.0 +/- 0.2 mU/kg . min (range, 0.3-2.4) were reduced by 67.4 +/- 4.6% and 94.6 +/- 2.1% by the two cortisol infusions, which yielded cortisol plateau concentrations in plasma of 4.24 +/- 0.41 and 6.09 +/- 0.68 microgram/100 ml, respectively . This sensitive feedback response to low cortisol concentrations was delayed, with no effect for about 20 min and maximal effect reached within 1 h . There was no evidence of a fast rate-sensitive feedback . Some increases in ACTH secretion were seen during the recovery period (errors are +/- SEM).

Med Klin, 1978 Sep 15, 73(37), 1277 - 80
{Cytological screening test for cervix cancer: EA-rosette-forming cells (author's transl)}; Noltenius H; Cell suspensions from the cervix may or may not contain EA-rosette-forming cells . In the case of non-rosette formation no further cytological examination is required . In case of rosette formation of moderate degree (10 cells per counting chamber) further cytological examination is necessary since in these cell populations atypical cells might be present . This procedure reduces the number of cytological examinations for about 50% and therefore entails considerable reduction of the load for cytological laboratories.

J Exp Med, 1978 Sep 1, 148(3), 674 - 91
Comparison of wild-type and subacute sclerosing panencephalitis strains of measles virus . Neurovirulence in ferrets and biological properties in cell cultures; Thormar H et al.; The neurovirulence of two wild type (wt) and seven Subacute Sclerosing Panencephalitis (SSPE) measles virus strains was tested in young adult ferrets by intracerebral (IC) inoculation of infected Vero cell suspensions . Wt strains Edmonston and Woodfolk and SSPE strains Mantooth, Halle, and LEC-S did not produce a detectable encephalitis in the ferrets, but caused a significant formation of serum antibodies against measles virus . SSPE strains LEC, IP-3, Biken, and D.R., on the other hand, were all neurovirulent in ferrets, particularly strain D.R . which caused an acute encephalitis in all inoculated animals . Strain Biken was of particular interest since it caused a subacute encephalitis in four of seven ferrets . The subacute encephalitis was characterized by a long incubation time, persistence of virus in the brain for at least 8 mo, widespread inflammatory lesions, and production of measles virus specific IgG in the brain . A study of the biological properties of the various measles virus strains showed that wt strains Edmonston and Woodfolk and SSPE strains Mantooth, Halle, and LEC-S produced free virus particles in significant titers both in Vero and ferret brain (FB) cultures . Cytopathic effect (CPE) with cell-fusion was marked in Vero cultures, whereas only minimal CPE and no cell-fusion were observed in the FB cultures . SSPE strains LEC, IP-3, Biken, and D.R., on the other hand, were mostly cell-associated in Vero and FB cultures, although atypical cell-free particles were produced by strains Biken and IP-3 . All four strains showed cell-fusing activity in FB cultures, particularly strain D.R., which was the only strain that spread more actively by fusion in FB than in Vero cultures . The results are discussed in relation to the neurovirulence of the various measles virus strains in adult ferrets . Pronounced cell-fusing activity in FB cells and cell-association with minimal or no production of cell-free virus seem to be essential to establish a brain infection in the animals.

Lab Invest, 1978 Sep, 39(3), 267 - 80
Hairy cells and macrophages: a comparative study; Palutke M et al.; Leighton tube cultures of peripheral blood leukocytes and splenic cell suspensions of 11 patients with hairy cell leukemia (leukemic reticuloendotheliosis) were utilized to compare characteristics of hairy cells and macrophages . Light and electron microscopy, both transmission and scanning, as well as cytochemical studies demonstrated several striking similarities to macrophages . They included phagocytosis of red cells, platelets, cellular debris, and latex particles, adherence to glass with development of long pseudopodia and cytoplasmic granules, alpha-naphthyl butyrate esterase activity and diffuse and granular periodic acid-Schiff positivity.

Immunology, 1978 Sep, 35(3), 463 - 9
Study of human T and B lymphocytes with heterologous antisera . III . Immunofluorescence studies on tonsil sections; Lamelin JP et al.; Lymphoid cells from human palatine tonsils were identified on tissue sections by membrane or intracellular immunofluorescence (IF) staining . Used in an indirect technique, an anti-IgM and an anti-HTLA (human T lymphocyte antigen) antiserum gave complementary patterns of membrane IF, characteristic of the follicular organization . When serial sections were stained for each of the five classes, immunoglobulin-containing cells from all classes were found . Their relative frequencies were, in decreasing order: IgG: 61.6%; IgA: 17.3%; IgM: 12%; IgE: 7.5%; IgD: 1.6% . These differed from those of the gut-associated lymphoid tissue (IgA greater than IgG greater than IgM) and of the peripheral lymph nodes (IgG greater than IgM greater than IgA), but were close to those of mesenteric nodes . The absence of secretory component in tonsil was an additional difference from gut-associated lymphoid tissue and the relatively high proportion of IgE-containing cells, in the absence of recognized atopy, is another feature in common with mesenteric lymph nodes . Finally, slight differences between these results and those obtained on tonsil cell suspensions suggest that some degree of selection probably occurs during the isolation procedure.

J Natl Cancer Inst, 1978 Sep, 61(3), 715 - 8
A reevaluation of B-lymphocyte levels in peripheral blood from cancer patients; Wood GW et al.; B-lymphocytes were quantitated in mononuclear cell suspensions derived from the peripheral blood of patients with various nonlymphoreticular cancers . The method used was anti-IgM and anti-IgD membrane immunofluorescence . The mean percentage of circulating B-lymphocytes in 78 cancer patients tested was 5.3 +/- 4.6 with a range of 0--18% . Those values were compared with a mean of 9.4 +/- 4.0 and a range of 3--20% for 46 apparently normal individuals . The difference was highly significant (P less than or equal to 0.001) . The mean percentage of B-cells in cell suspensions from 43 patients that were tested prior to treatment was 5.8 +/- 4.8 with a range of 0--18% . Very low values were observed both in the presence and absence of therapy, and a correlation with stage of disease could not be established . The low values were associated with decreased T-cell numbers and significantly increased monocyte levels . The fact that those values were significantly lower than have been reported previously for cancer patients was discussed as was the identity of the cells that previously had been counted as B-lymphocytes.

J Immunol, 1978 Sep, 121(3), 973 - 7
Characterization of a B cell defect in the NZB mouse manifested by an increased ratio of surface IgM to IgD; Cohen P et al.; In an effort to define the cellular basis of abnormalities in polyclonal B cell activation previously noted in NZB mice, the surface immunoglobulin (sIg) isotypes of spleen cells from NZB mice were examined . After lactoperoxidase-catalyzed radioiodination, the cell surface immunoglobulins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) . Spleen cells from 8- to 10-week-old NZB mice were found to have an increased ratio of cell surface IgM/IgD compared to cells from 11 control strains . The altered ratio of sIg isotypes was not a consequence of increased proteolytic activity present in NZB cell suspensions or of the presence of cytophilic antibody or autoantibody . Ontogenetic studies of the sIgM/sIgD (mu/delta) ration on splenocytes from NZB and BALB/c mice revealed that the former cells had higher mu/delta ratios as early as 2 weeks after birth . By 4 weeks of age the mu/delta ratios were equivalent . Between 4 weeks and 1 year of age, the mu/delta ratios on NZB splenocytes remained constant whereas those on BALB/c splenocytes decreased and reached adult levels at 6 weeks.

J Immunol, 1978 Sep, 121(3), 1007 - 9
In situ cytotoxic T cells in a methylcholanthrene-induced tumor; DeLustro F et al.; The in situ localization of cytotoxic T-cells was examined in a methylcholanthrene-induced fibrosarcoma . The MCA 2 tumor was initiated in this laboratory and utilized before extensive in vivo passage . Tumor cell suspensions were separated by unit velocity sedimentation . The T cell-enriched tumor-derived fractions and spleen cells from MCA 2-bearing mice were cytotoxic for in vivo isolated MCA 2 and in vitro cultured MCA 2 tumor cells, but not for SAD2 tumor cells . The cytotoxic activity of effector cells isolated from MCA 2 tumors was abrogated by treatment with anti-theta serum plus complement . The significance of cytotoxic T cells with in a progressing tumor is discussed.

Proc Natl Acad Sci U S A, 1978 Sep, 75(9), 4549 - 52
Endogenous RNA tumor viruses are activated during chemical induction of murine plasmacytomas; Armstrong MY et al.; Plasmacytomas are induced in BALB/c mice by the intraperitoneal injection of pristane (2,6,10,14-tetra-methylpentadecane) after a latent period of six months and more {Anderson, P . N . & Potter, M . (1969) Nature 222, 994-995} . Spleen cells mesenteric lymph node cells, thoracic lymph node cells, and peritoneal exudate cells were prepared from pristane-treated and control uninjected BALB/c mice during the course of a 10-month period, and these cell suspensions were tested for the release of infectious murine leukemia viruses . Endogenous ecotropic and xenotropic murine leukemia viruses were expressed in pristane-treated mice during the latter part of the tumor induction period, in those cell populations in which transformed plasma cells appear, namely, peritoneal exudate cells and thoracic lymph node cells . The significance of preferential expression of both ecotropic and xenotropic murine leukemia virus in target cell populations following the administration of a carcinogen is discussed in terms of the possible formation of an oncogenic variant virus.

Biochim Biophys Acta, 1978 Aug 17, 542(2), 315 - 29
Mechanisms of corticotropin action in rat adrenal cells . I . The effects of inhibitors of protein synthesis and of microfilament formation on corticosterone synthesis; Crivello JF et al.; The contributions of protein synthesis and formation of microtubules and microfilaments to corticotropin-stimulated steroidogenesis in rat adrenal cell suspensions has been assessed by use of a series of inhibitors to each function . Five inhibitors of protein synthesis (cycloheximide, puromycin, blastocidin S, anisomycin, and trichodermin) each exhibited time-dependent inhibition of corticotropin-stimulated steroidogenesis . For the first 30 min, steroidogenesis was more extensively inhibited than protein synthesis, after which the effectiveness of the inhibitors diminished on steroidogenesis but not on protein synthesis . The reversal effect was not observed at high levels of inhibitors . One inhibitor of microfilament formation (cytochalasin B) and four inhibitors of microtubule formation (colchicine, podophyllotoxin, vinblastine sulfate and griseofulvin) inhibited steroidogenesis without inhibiting protein synthesis and without any reversal effect with prolonged incubation . The actions of all ten inhibitors were shown to be fully reversible . Cell superfusion of adrenal cells showed that the decay of steroidogenesis upon addition of all the protein synthesis inhibitors was similar to decay upon removal of corticotropin from the medium (t1/2 = 4--6 min) . Recoveries from inhibition upon removal of the inhibitors were similar to each other and comparable to initial corticotropin stimulation of the cells (lag of 3--5 min, t1/2=7--9 min) . Similar kinetics of inhibition and recovery were observed for vinblastine sulfate while a direct inhibition of cytochrome P-450scc by aminoglutethimide was complete within 1 min and was rapidly reversed . Injection of each inhibitor (all classes) into hypophysectomized rats inhibited the elevation of plasma corticosterone by corticotropin . The extent of cholesterol combination with cytochrome P-450scc in adrenal mitochondria isolated from these rats was also decreased by all of the inhibitors . Decreases in plasma corticosterone correlated directly with decreases in cholesterol combination with cytochrome P-450scc (r=0.94) . It is concluded that protein synthesis and steroidogenesis must be intimately coupled probably due to the requirement of a labile protein for cholesterol transport to cytochrome P-450scc . An involvement of microtubules and microfilaments in this process is clearly indicated.

Cell Tissue Res, 1978 Aug 16, 191(3), 379 - 88
Culture of human pituitary prolactin and growth hormone cells; Snyder J et al.; Fragments of pituitary tissue obtained from a total of 37 patients with either breast cancer, diabetic retinopathy, galactorrhea, or acromegaly were dissociated into single cell suspensions prior to cell culture . Release of human growth hormone (hGH) and human prolactin (hPRL) into the culture medium was measured by radioimmunoassay . During a 3-week culture period, prolactin cells released 9--13 times the intracellular levels of hPRL at the time of seeding, whereas hGH release from growth hormone cells was only 1--2 times that of their initial intracellular level during this same time . Both growth hormone and prolactin cells retained distinctive ultrastructural features during culture . The prolactin cells responded to TRH stimulation by elevated release of PRL into the medium . No evidence for mitotic division of prolactin cells in vitro was found.

Biochem J, 1978 Aug 15, 174(2), 663 - 6
The lipoprotein lipase (clearing-factor lipase) activity of cells isolated from rat cardiac muscle; Chohan P et al.; The total lipoprotein lipase activity recovered in suspension of cells prepared from adult rat hearts was unaffected by the nutritional state of the animals used . The enzyme activity present in the cell suspensions was almost exclusively associated with the cardiac muscle cells present as the major cell type.

Appl Environ Microbiol, 1978 Aug, 36(2), 213 - 6
Progesterone biotransformation by plant cell suspension cultures; Yagen B et al.; Progesterone was converted to 5alpha-pregnane-3alpha-ol-20-one, delta4-pregnene-20alpha-ol-3-one, delta4-pregnene-14alpha-ol-3,20-dione, delta4-pregnene-7beta,14alpha-diol-3,20-dione, and delta4-pregnene-6beta,11alpha-diol-3,20-dione by cell cultures of Lycopersicon esculentum . Cell cultures of Capsicum frutescens (green) metabolized progesterone to delta4-pregnene-20alpha-ol-3-one in very high yield, and Vinca rosea yielded delta4-pregnene-20beta-ol-3-one and delta4-pregnene-14alpha-ol-3,20-dione . A stereospecific reduction of the keto groups and a double bond and stereospecific introduction of hydroxyl groups at the 6, 11, and 14 positions have been observed . The mono- and dihydroxylated progesterones have not previously been reported as metabolic products of progesterone by plant cell systems and represent de novo hydroxylation of a nonglycosylated steroid.

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