Infect Immun, 1984 Jan, 43(1), 347 - 52 Immunostimulation by Legionella pneumophila antigen preparations in vivo and in vitro; Friedman H et al.; Injection of Legionella pneumophila antigen, either killed vaccine or soluble sonicate thereof, resulted in an enhanced antibody response by mouse spleen cells to sheep erythrocytes as determined by the hemolytic plaque assay . Enhancement was dose dependent and reached a peak response at a concentration of 10(7) bacteria or 50 micrograms of sonicate per animal . Larger doses of antigen were less stimulatory or even depressed the antibody response . Similar enhancement of antibody formation by normal spleen cell cultures to sheep erythrocytes in vitro occurred in the presence of graded amounts of L . pneumophila vaccine or sonicate . In addition, the L . pneumophila antigen stimulated enhanced background antibody formation in vitro in the absence of sheep erythrocytes or specific antigen . It appeared likely that the immunoenhancing activity of the L . pneumophila extract may be unrelated to the presence of lipopolysaccharide since boiling the antigen preparation eliminated much of the antibody-enhancing properties of the extract . A large-molecular-weight surface component from L . pneumophila was also immunomodulatory in vitro . Immunostimulation appeared to be related to effects on macrophages since adherent spleen cell populations rich in macrophages, when derived from spleen cell suspensions incubated with L . pneumophila antigen in vitro, stimulated enhanced antibody formation by normal mouse spleen cells in coculture experiments . Further investigations concerning the mechanism of immunomodulation by L . pneumophila antigen in vivo and in vitro appear to be warranted. Cancer Res, 1984 Jan, 44(1), 324 - 31 Isolation of oval cells by centrifugal elutriation and comparison with other cell types purified from normal and preneoplastic livers; Yaswen P et al.; Oval cells and biliary epithelial cells were isolated from livers of rats fed a choline-deficient diet containing 0.1% ethionine and from normal rat livers, respectively . Nonparenchymal cell suspensions prepared from these livers by collagenase perfusion followed by digestion of undissociated tissue with 0.1% collagenase, 0.1% Pronase, and 0.004% DNase I were separated into six fractions by centrifugal elutriation . Cells in each fraction were characterized histochemically for gamma-glutamyl transpeptidase, peroxidase, alkaline phosphatase, and glucose-6-phosphatase activities, and for albumin and alpha-fetoprotein by immunocytochemical methods . Cells from Fraction 5 of the elutriation procedure had various features predicted for oval cells and were selected for further studies . The cell yield in this fraction, from each preneoplastic liver, was 5.7 X 10(7) cells, 93 +/- 2% of which were gamma-glutamyl transpeptidase positive, 6 +/- 1% peroxidase positive, 61% albumin positive, and 29% alpha-fetoprotein positive . Cells in this fraction have a median diameter of 13.1 micron and are diploid and cycling . The majority of these cells has morphological features characteristic of biliary epithelial cells, although some cells display features intermediate between duct cells and hepatocytes . Nucleic acid hybridization using specific probes revealed that these cells contain albumin and alpha-fetoprotein messenger RNAs, while hepatocytes from normal and preneoplastic liver contain only albumin messenger RNA . Biliary cells obtained from normal livers do not contain albumin messenger RNA . The large-scale purification and characterization of cell populations from preneoplastic livers is an important step in elucidating the cellular derivation of liver tumors. Leuk Res, 1984, 8(3), 425 - 8 The intracellular location of terminal transferase does not vary with cell cycle stage; Barr RD et al.; The biochemical activity of terminal transferase (TdT) in the thymocytes of leukemic AKR mice has no relationship to cell cycle stage, unlike the activity of replicative DNA polymerase which increases during the period of DNA synthesis . Moreover, such assays of DNA polymerase alpha reveal a shift in enzyme activity from cytoplasm to nucleus during S phase . In the present study, the role of TdT in DNA metabolism was explored further by examining the intracellular location of the enzyme during cytokinesis . Single cell suspensions of thymocytes from leukemic AKR mice were partially synchronized by velocity sedimentation in a sucrose gradient at unit gravity and harvested according to cell cycle stage . The content and location of TdT in individual cells was determined by indirect immunofluorescence using a rabbit antiserum to calf thymus TdT as the primary antibody . There was no relationship of fluorescence intensity or of the proportion of TdT-positive cells to cell cycle stage . In all samples examined (n = 6) the enzyme was located almost entirely in the nucleus throughout cytokinesis . These results do not support the hypothesis that the intracellular location of TdT may vary with cell cycle stage and a role for the enzyme in DNA synthesis remains to be defined. Biomed Pharmacother, 1984, 38(7), 332 - 7 Experimental and clinical studies on aclarubicin in the treatment of solid tumors; Kumai K et al.; Experimental and clinical studies were performed on aclarubicin in the treatment of solid tumors . In experimental cancer chemotherapy using human tumor xenografts transplanted to nude mice, aclarubicin showed a moderate antitumor effect (retardation of tumor growth) and nearly the same spectrum of activity in vivo as Adriamycin (doxorubicin) . In in vitro sensitivity tests using 3H-thymidine uptake inhibition of a single cell suspension prepared from xenografts, aclarubicin showed a stronger inhibition than that of Adriamycin, mitomycin C and cyclophosphamide . In phase II clinical studies in patients with solid tumors, 3 intravenous dose schedules {schedule A: 20 mg (equal to 14 mg/m2) daily every other week, schedule B: 40 to 60 mg (28 to 42 mg/m2) twice a week, and schedule C: 60 to 100 mg (42 to 70 mg/m2) once a week} were investigated . Aclarubicin produced a 15 to 20% response rate for carcinomas of the stomach, lung, breast and ovary by schedules A and B . Dose-schedule limiting factors were digestive and hematologic toxicity. Eksp Onkol, 1984, 6(1), 70 - 2 {Spectrophotometric method of evaluating tumor cell agglutination induced by lectins}; Viadro MM; The lectin (PHA and Con A) induced agglutination of a human tumour cell line (lung adenocarcinoma and osteosarcoma) was estimated by the spectrophotometric method . A decrease in the optic density for 1 min (delta D) of cell suspension and the time (t0) necessary for a complete sedimentation of cells (at delta D = 0) were used as quantitative indicators of agglutination . An increase in the concentration of tumour cells and lectins resulted in an increase of delta D and a decrease of t0 . The results of spectrophotometry were correlated with the microscopic study data for tumour cells agglutination. Biorheology Suppl, 1984, 1, 249 - 53 An improved filtration rate for measuring red cell deformability; Sowemimo-Coker SO et al.; In order to follow the filtration of a red cell suspension with time, the filtration technique described (1) has been modified . The red cell suspension is filtered through a polycarbonate membrane filter (pore diameter 5 micron) under gravitational force . The filtrate is collected in a plastic tube connected to an isometric transducer, the output of which is registered on a chart recorder . The linear part of the curve obtained is used to calculate the slope and the relative filterability (RF) ie the ratio of the rate of flow of the red cell suspension to the rate of flow of the suspending medium . The reproducibility of the technique is demonstrated by a less than 5% coefficient of variation in one blood sample less than 5% interobserver variation and a weekly variation from the same donor of less than 5% . The fast filtration rate of a highly diluted red cell suspension (0.5-1%) may be followed with this technique, taking the first 15 seconds to calculate it . The technique has proved useful in detecting differences in red cell deformability in connective tissue disorders (Scleroderma, Raynaud's phenomenon) also between stored and freshly prepared red cell suspension and its improvement by drugs (pentoxifylline, dipyridamole). J Neurochem, 1984 Jan, 42(1), 175 - 84 Growth kinetics, cell shape, and the cytoskeleton of primary astrocyte cultures; Goldman JE et al.; We examined correlations among growth kinetics, cell shape, and cytoskeletal protein content in rat astrocytes grown in primary culture . Cell suspensions from brains of newborn rats were seeded at densities from 0.2 to 3 X 10(5)/cm2 . At initial densities above 1 X 10(5) the population increased to reach confluency by 10-12 days, after which cell number remained stable for many weeks . At low initial densities, 0.2-0.4 X 10(5)/cm2, cells did not increase in number . Final density increased with increasing plating densities . High-density cells had small perikarya and several long cytoplasmic processes; low-density cells appeared flat and polygonal . All cultures were almost entirely astrocytic, as judged by immunofluorescent staining with antiserum against glial fibrillary acidic protein (GFAP) . Cytoskeletal proteins were analyzed by gel electrophoresis after extraction from cells with nonionic detergent . Relative amounts of the proteins differed, in that low-density cells contained large amounts of cytoskeletal actin relative to the intermediate filament (IF) proteins vimentin and GFAP, whereas high-density cells contained relatively less actin and more IF proteins . Such differences in cytoskeletal proteins between the high- and low-density cultures were mirrored in the relative rates of synthesis of the cytoskeletal proteins . In the low-density cells amino acid incorporation into cytoskeletal-associated actin was more active than that into the IFs, whereas in the high-density cells higher rates of IF protein synthesis were observed. Trans Assoc Am Physicians, 1984, 97, 332 - 6 Rapid thyroid hormone action in vitro in the absence of new protein synthesis; Sterling K et al.; Studies were carried out on the effect of triiodothyronine (T3) on the oxygen consumption of dispersed rat liver cells incubated for 2 hr at 37 degrees C . Thyroidectomized SD-NIH rats were kept on a low iodine diet with calcium chloride in the drinking water for 4 weeks or longer to assure hypothyroidism, verified by low serum thyroxine and T3 concentrations . Liver cells were obtained by portal vein perfusion with oxygenated collagenase-enriched Krebs-Ringer-bicarbonate buffer, after the method of Berry and Friend . Cell viability was evaluated by morphology, by trypan blue exclusion, and by biochemical parameters prior to 2-hr incubations with or without added hormone . The oxygen consumption of cell suspensions was measured with the Clark oxygen electrode after the 2-hr incubations at 37 degrees C with oxygenation of the flasks and alanine (5-10 mM) as substrate . In 31 experiments the oxygen consumption (QO2) was enhanced to 121% of control values with T3 in the medium at 3.3 nM ("physiological" level) and with an even greater effect (138% of control values) with 300-1000 nM T3 ("hyperthyroid" level) . Cycloheximide at 100 microM was used to inhibit new protein synthesis by incubated hepatocytes . In 18 parallel experiments with cycloheximide blockade, no alteration of the stimulatory effect of T3 was evident . The results signify that incubated liver cells show an early response to thyroid hormone by extranuclear pathways that do not require new protein synthesis. Exp Lung Res, 1984, 7(2), 113 - 22 Separation and characterization of lymphocytes from rat lung parenchyma; Kumar RK; Rat pulmonary parenchymal tissue was disaggregated into a single cell suspension by treatment with collagenase . A cell population enriched for lung lymphocytes was separated by depletion of adherent cells on a Sephadex G-10 column: 16.7 +/- 2.7 X 10(6) cells per animal were recovered . On the basis of cytochemical and morphologic criteria, the separated cells contained greater than 80% lymphocytes, with a viability of 80-90% . The distribution of lymphocyte subpopulations was determined by indirect immunoperoxidase staining with appropriate monoclonal antibodies . Separated lung lymphocytes exhibited a proliferative response in vitro to phytohemagglutinin and concanavalin A . Supernatants from lung lymphocytes stimulated with concanavalin A contained lymphokine activity that could be demonstrated in a leukocyte procoagulant activity assay. Pharmacol Biochem Behav, 1984, 21 Suppl 1, 31 - 4 Effect of cesium and potassium salts on survival of rats bearing Novikoff hepatoma; Messiha FS et al.; The effect of CsCl on the life span of female Sprague-Dawley rats innoculated with Novikoff's hepatoma was studied as a function of both pre- and post-treatment with CsCl and as a function of the inoculant dose . The effect of KCl on the CsCl treatment was also studied . Rats treated with CsCl for 12 consecutive days prior to or immediately after inoculation with 1.0 ml of viable hepatoma cell suspension showed an increase in mortality score from corresponding controls . Conversely, increases in the dose of the inoculant resulted in delaying the onset of toxicity in rats receiving the Cs-treatment after inoculation as evidenced by a decrease in mortality . Availability of KCl in drinking water ad lib further decreased total mortality when given alone but not when combined with CsCl . The results indicate a dose-dependent paradoxical effect of CsCl on Novikoff hepatoma cell toxicity and suggest a critical intercellular balance requirement between Cs+ and K+ on the effect studied. Exp Cell Biol, 1984, 52(6), 371 - 82 Characterization of human bone marrow long-term cultures; Horikoshi A et al.; In an attempt to more closely simulate the native hematopoietic environment, human bone marrow bony matrix was cultivated in long-term human bone marrow cultures . Sternal bone marrow curettings (i.e., 'bony matrix') were cultured with and without autologous bone marrow single cell suspensions . Fresh media were provided at weekly intervals and the 'harvested' cells were assayed for CFU-gm (i.e., the granulocyte-macrophage precursor) . Bone marrow bony matrix alone was not competent to maintain CFU-gm production, although early in the culture nucleated cells and CFU-gm were recruited from the bony matrix . A dose of 850 rad of X-radiation to the bone marrow matrix damaged the hematopoietic growth-promoting effects of the adherent cell layer, which was, however, rapidly reconstituted by an inoculation of intact autologous bone marrow cells . Additional investigations revealed that, whereas the addition of hydrocortisone to this culture system did not alter the maintenance of CFU-gm, recharging the cultures with fresh autologous marrow maintained CFU-gm for 10 weeks . These data indicate that human bone marrow stroma is more sensitive to X-irradiation in vitro than in vivo, and the bone marrow hematopoietic microenvironment provided by its bony matrix seemed to be less effective in vitro than in vivo with respect to the maintenance of hematopoietic precursor cells. Biorheology, 1984, 21(4), 603 - 15 Structure of blood flow through a curved vessel with an aneurysm; Niimi H et al.; A fine structure of blood flow through a curved vessel with an aneurysm was studied in in vitro experiments in relation to rheological factors of arterial diseases such as arteriosclerosis or thrombosis . On the basis of the in vivo data related to cerebral circulation, red blood cell suspension was flowed through curved vessel models with an asymmetrical aneurysm . Flow visualization was made with a microscope 16 mm cinecamera-TV monitor system, and the velocity profile was measured using the laser Doppler velocimeter . Vortices induced in aneurysm influenced flow structure and velocity at the presence of the secondary flow due to the vessel curvature . This suggests strongly that blood flow in curved arteries with an aneurysm must be understood under the influence of the secondary flow. Tissue Cell, 1984, 16(4), 483 - 97 An in vitro model for studies of intercellular communication in cultured rat anterior pituitary cells; Wilfinger WW et al.; The formation of intimate associations among different hormone-secreting cells within the rat adenohypophysis may serve as a possible site for physiologic regulation . In this report we describe a high density plating method which enables us to study cell-to-cell interactions within anterior pituitary cell cultures . Trypsin-dispersed pituitary cell suspensions attach rapidly (within 6 hr) and quantitatively (95-97%) to glass or plastic surfaces when plated in medium containing microM calcium concentrations (pH 7.6-7.8) . Freshly plated cell suspensions obtained from female pituitary glands contained subpopulations of mammotrophs 49.3%, somatotrophs 30.3%, gonadotrophs 12.6%, corticotrophs 3.4% and thyrotrophs 1.5% . Epithelial cell colonies were formed during a 3-day culture period as the cells flattened and re-established contacts with neighboring cells . Freeze-fracture electron microscopic analysis of these colonies produced morphological evidence for direct intercellular contacts among the hormone-secreting cells . Large areas of tight junctions and small gap junctions were identified on the membranes of the epithelial cells within these colonies . Cells which contained tight junctions usually contained microvilli and morphological signs of active hormone secretion . Small junctional plaques containing tightly packed intramembrane particles were also occasionally found on the membranes of cells which were actively secreting pituitary hormones . The high density plating procedure which is described in this report provides greater opportunity for cell-cell interaction and thus may prove to be a useful model for evaluating the role of intercellular communication within this tissue. Biorheology, 1984, 21(3), 405 - 14 Shear viscoelasticity of suspensions of biological cells with viscoelastic membrane; Abe K et al.; To discuss the relaxation phenomena of biological cell suspensions, we have calculated the complex intrinsic viscosity of the dispersion of spherical cells with a viscoelastic membrane as a function of the frequency taking account of interfacial tension at both the interfaces of the membrane . The Voigt model is used to describe the viscoelasticity of the cell membrane . In general it is possible for four relaxations to exist . Under a finite membrane viscosity it is predicted that there exist two relaxations . The amplitude of relaxation for the shorter relaxation time is larger than that for the longer relaxation time . The results are compared with the experimental ones. Biorheology, 1984, 21(3), 379 - 91 Deformation of red blood cells and the viscoelastic properties of a concentrated red cell suspension; Murata T; The viscoelastic properties of a concentrated red cell suspension in which red cells do not form rouleaux are discussed from a theoretical point of view . An elastic spherical shell filled with a viscous fluid is considered as a model of a normal red cell . A cell method is used to consider finite concentration of suspended particles . On the assumption that the deformation from a spherical shape is very small, the shape of a deformed shell in a shear flow and the constitutive equation of the suspension are derived. Jpn J Physiol, 1984, 34(6), 1015 - 27 Change in PCO2 in red cell suspension following bicarbonate shift; Shimouchi A et al.; To reveal the CO2 diffusion process into and out of the red blood cell (RBC), changes in PCO, following the HCO3- shift were examined . The RBC suspension was mixed at 37 degrees C with saline solution having different HCO3- concentrations . In proportion to the intracellular HCO3- change caused by the HCO3- shift, the PCO2 change was increased . The rate of change increased as the hematocrit and the initial intracellular HCO3- content decreased . For calculating the above PCO2 change, a theoretical equation was derived from the Henderson-Hasselbalch equation and the relation between both the changes in buffer base and intracellular pH . The calculated PCO2 change coincided well with the measured value, suggesting the validity of the theoretical equations. Virchows Arch A Pathol Anat Histopathol, 1984, 404(4), 351 - 8 S-100+ lymph node neoplasm . Report of a case with histological AL and immunological features intermediate between T cell lymphoma and malignant histiocytosis; Ruco LP et al.; A 16-yr-old white female was affected by continuous fever, pancytopenia with relative increase of T-8 lymphocytes, severe bone marrow hypoplasia, generalized lymphadenomegaly and splenomegaly . A first lymph node biopsy, obtained at the onset of the disease, was involved by a paracortical tumor with some S-100+ "lymphocyte-like" cells in the neoplastic areas; in the cell suspension, 70-80% of cells were E4+/E37+ lymphocytes with prevalent expression of the T-8 phenotype (52%) . A second lymph node biopsy, obtained five months later, was involved by a diffuse proliferation of S-100+ cells with high mitotic activity; in the cell suspension, the majority of cells were E-/T-11+/T-3+/T-8+ . At the TEM level, the neoplastic cells were characterized by regular or indented nuclei with finely dispersed chromatin and by regular or indented nuclei with finely dispersed chromatin and by irregular cytoplasmic profiles with thick pseudopodia-like projections . The possibility is discussed that this neoplasm may share some similarities with the T-gamma lymphoma being part of a poorly described group of tumors with intermediate features between T cell lymphoma and malignant histiocytosis. Dev Biol Stand, 1984, 56, 659 - 78 An evaluation of the stability of Brucella abortus strain 19 reduced dosage lyophilized vaccines produced by different methods; Angus RD; Replicate lots of multiple dose lyophilized Brucella abortus strain 19 vaccine were prepared having four different cell concentrations and four different fill volumes . In addition, two different size vials utilizing cells prepared by three different methods were studied . This vaccine was maintained at four different storage temperatures and the viability determined periodically . There was no appreciable loss in viability that could be attributed to the method of cell preparation; however, marked differences in viability were associated with cell concentration and/or prelyophilization fill volume and the two vial sized . The optimal prelyophilization cell suspension contained 25 to 35 X 10(9) viable Brucella 1 per ml . The better lyophilization vials had dimensions which minimized the surface to volume ratio of the postlyophilization pellet . Based on these studies it was concluded that production of large volumes of reduced dosage lyophilized vaccine is feasible and that the vaccine produced will meet specifications currently being implemented in the United States . These specification will require that each two ml dose of vaccine contain between three and ten X 10(9) viable organisms of B . abortus strain 19. Clin Lab Haematol, 1984, 6(2), 165 - 9 Micro-aggregate content of red cell suspensions stored in saline adenine glucose mannitol optimal additive solution; Napier JA et al.; The micro-aggregate content of blood collected into conventional CPDA-1 preservative was compared with that of red cells stored in saline adenine glucose and mannitol optimal additive preservative solution (SAG-M) . The results show that the optimal additive packs from which either platelet rich or platelet poor plasma have been removed contain 38% of the micro-aggregates in CPDA-1 blood . When platelets, plasma and the buffy coat are also removed, the residual micro-aggregates amount to only 16% of those in CPDA-1 whole blood . No differences were seen between the amount of haemolysis in any of the red cell preparations . From these results and previously published guidelines for the use of micro-aggregate filters with whole blood (International Forum 1977) it may be concluded that there is no place for the routine use of micro-aggregate filters with optimal additive preserved blood unless over 12 units are likely to be transfused. Eur J Nucl Med, 1984, 9(7), 320 - 2 A simple and safe technique for sterile autologous platelet labelling using "Monovette" vials; Sinzinger H et al.; A simple technique of autologous platelet labelling is described, which allows labelling within 40 min, and has the advantage of low costs, as no laminar air flow is required . Blood (16 ml) was withdrawn into 4 ml ACD, 500 ng prostacyclin was added . After 10 min sedimentation the vials were centrifuged for 5 min at 150 g . The plateletrich plasma in the supernatant was centrifuged at 500 g for 10 min to obtain a platelet pellet . The platelet-poor plasma was preserved in a sterile syringe and the platelet pellet was resuspended in 1 ml tyrode buffer . The cell suspension was labelled at 37 degrees C for 5 min with 100 muCi 111In-oxine sulphate and reinjected after dilution with the plasma . Mean labelling efficiency was 90% +/- 3%, mean recovery 2 h after reinjection 76% +/- 3% (mean +/- SD). Cytobios, 1984, 39(155-156), 165 - 70 Cytochrome system in cultivated Mycobacterium lepraemurium; Ishaque M; The respiratory pigments of cell suspensions of Mycobacterium lepraemurium cultivated on Ogawa egg-yolk medium were investigated spectrophotometrically . The results obtained showed that whole cell suspensions of both Kumato and Hawaiian strains contained flavins, cytochromes of the a2 and b type, as well as a CO-binding pigment similar to cytochrome o . The whole cell suspensions of M . lepraemurium did not show detectable quantities of c type cytochrome . However, cytochrome c was present in small amounts, and its presence became evident in the dithionite-reduced minus oxidized difference spectra of pyridine haemochromogens prepared from in vitro grown cells of M . lepraemurium. Biomed Biochim Acta, 1984, 43(2), 187 - 96 Flow cytometric measurements of phagocytosis . I . A methodical and comparative study; Glass W et al.; A flow cytometric technique is described for measurement of phagocytic activity in human leucocytes using FITC-labelled latex particles (0.77 micron) . Cell suspensions separated from peripheral blood by dextran sedimentation were hemolyzed to avoid particle uptake by erythrocytes . The leucocytes were incubated for various time intervals with a standardized solution of 2 x 10(7) FITC-labelled latex particles per 2 x 10(5) leucocytes in 0.6 ml medium . Relative fluorescence per cell was measured on the basis of 10(5) cells, and a simple technique has been described to evaluate data characteristic for different steps of phagocytosis and to discriminate between phagocytizing and non-phagocytizing cells . In comparison, rice starch phagocytosis has been measured microscopically . A positive correlation between both methods has been found in 11 patients with different disease-related phagocytic capacity. Acta Histochem Suppl, 1984, 30, 117 - 27 {Impulse cytophotometry and catamnesis in breast neoplasms}; Krug H et al.; CEll suspensions from 62 cancers of breast were investigated by flow cytophotometry after staining with pepsin-Ethidium bromide . In all patients a radical operation was made, followed by radiotherapy . The surviving patients were observed for 5 years . From the DNA-histograms 48% of the tumours were classified as diploid (or peridiploid), 40% as polyploid and 11% as aneuploid . Concerning ploidy a rank with worsening prognosis was found from diploid over polyploid to aneuploid cancers . In this sense bad prognosis means: dead or relapse during 5 years, histologically undifferentiated tumours, great primary tumour, metastasis in lymph nodes . In diploid tumours bad prognosis is indicated by a higher part of S- and G2-phase nuclei in the flow histograms . Most of the findings, but not all, are proved statistically . Now as ever, histological differentiation is still the most easily statement for prognosis. J Urol, 1984 Jan, 131(1), 22 - 32 Local chemotherapeutic effects in bladder cancer demonstrated by selective sampling and flow cytometry; Farsund T et al.; A method is described by which the effect of intravesical chemotherapy can be monitored . Cytological samples obtained selectively during treatment were used for morphological and flow cytometric studies, and isoantigen (A, B and H) assessment in 2 patients with urothelial cancer . With flow cytometry even small aneuploid populations in the urothelium could be identified . From the histograms the urothelium was seen to contain 2 different cell populations: 1) diploid and 2) aneuploid . The ratio between aneuploid and diploid cells decreased significantly during treatment . Treatment was continued until no evidence of aneuploid cells could be identified in the histograms . Thus, it is demonstrated that intravesical chemotherapy for certain types of bladder cancer can eradicate the aneuploid cell population . A good correlation was found between cytological studies and flow cytometric measurements . Isoantigen assessment was done in the cell suspension used for morphological and flow cytometric studies . Isoantigen assessment also showed loss of antigens after completion of treatment, indicating that the diploid population was not normal biologically . Thus, 3 parameters can be correlated and related also to topography. Cent Nerv Syst Trauma, 1984 Fall, 1(1), 47 - 56 Intracerebral grafting of neuronal cell suspensions into the adult brain; Gage FH et al.; General principles of intracerebral grafting are presented in overview . The development and use of the dissociated neuronal cell suspension method are described as a new method for neural transplantation . Experiments are described involving fetal dopamine cells transplanted to adult striatum and fetal cholinergic cells transplanted to the hippocampal formation, as primary examples . The main focus of this review is related to results of cell survival and axonal elongation. Folia Histochem Cytobiol, 1984, 22(3-4), 179 - 86 The modified method for isolation and culture of highly homogeneous Leydig cell population from rat testes; Janecki A et al.; A modified method for isolation and culture of a pure population of rat Leydig cells is described . For obtaining crude interstitial cell suspension, decapsulated testes were dispersed in 0.02% collagenase solution in Ca2+, Mg2+--free Hanks medium for 1 hour . Then, approx . 5 X 10(7) cells were centrifuged in 10-90% discontinuous, isoosmotic Percoll gradient at 3000 g for 20 min . The cells from eight fractions obtained were collected and cultured in Eagle's MEM for 4 days . Using morphological methods, 1.059-1.070 g/ml density fraction contained 97% and 1.070-1.080 g/ml fraction contained 90% viable Leydig cells . The cells secreted testosterone to the culture medium and responded to LH stimulation with over four-fold increase in hormone secretion. Vet Hum Toxicol, 1984, 26 Suppl 2, 11 - 3 Hepatic and testicular aldehyde dehydrogenase in tumor-bearing mice; Messiha FS; The interrelationship between certain dehydrogenases and a hepatic tumor was studied in mice . A rapidly growing hepatoma, Novikoff hepatoma, was transplantable from rats to mice after serial passages in Sprague-Dawley albino mice . Mice inoculated with viable tumor cell suspension were sacrificed 14, 18, 21 or 34 days thereafter . Hepatic cytoplasmic and mitochondrial aldehyde dehydrogenase (ALDH) were measured in addition to liver alcohol dehydrogenase (ADH) and testicular ALDH . Hepatic cytoplasmic and mitochondrial ALDH were markedly inhibited from controls at all time periods studied . Likewise, testicular ALDH was inhibited from respective controls in Novikoff hepatoma-bearing mice . No changes were measurable in hepatic ADH of hepatoma-bearing mice . The enzyme kinetics studied show a reduction in Vmax and an alteration in the apparent Km 34 days after tumor inoculation . Further analyses of hepatic mitochondrial ALDH showed that the inhibition was similarly present in the enzyme with the low and the high Km property . The results suggest that changes in the specific activity and property of ALDH may be a useful tool as a biochemical concomitant to both development and progression of the hepatoma studied. Crit Rev Biomed Eng, 1984, 11(4), 281 - 311 Methods of complex impedance measurements in biologic tissue; Ackmann JJ et al.; Bioelectric impedance measurements have been used to monitor a variety of physiologic events . While important insights have been gained and useful techniques developed, there are a number of limitations to the methods usually employed . Among these are the inability to define current pathways in complex systems and the inability to distinguish between volumetric changes and materials property changes . Methods that have been used successfully in materials science can be used to address these limitations: these methods involve measurements of both real and reactive components over a wide frequency range coupled with various plotting and analytic techniques . Accurate measurement of the reactive component is inherently difficult since biologic systems are highly conductive . In addition, safety considerations have generally limited bioelectric impedance measurements in humans to frequencies above 20 kHz . For these reasons the techniques have not been widely applied in vivo; however, the techniques have been used in studies of cell suspensions and biologic tissue . This paper reviews these applications, summarizes the theory from a materials science viewpoint, discusses the instrumentation considerations for extension of the techniques to other studies, and presents more recent applications. Cancer Immunol Immunother, 1984, 18(3), 223 - 5 Effect of cis-platinum on human blood monocyte function in vitro; Nielsen H; The influence of cis-diamminedichloroplatinum(II) (cis-DDP) on human blood monocyte functions in vitro was studied . With cis-DDP added to the cell suspensions in concentrations between 10(2) and 10(-6) microM just before assay of monocyte functional capacity no significant changes in chemotactic, chemokinetic, phagocytic, or fungicidal activities were observed . However, with preincubation at 1 microM for 60 min cis-DDP selectively inhibited chemotaxis, but not chemokinesis or phagocytosis . This inhibition was more pronounced at 37 degrees C than at 4 degrees C, and was not reversed by washing of the cells . The implications of these findings for clinical oncology are discussed. Biomed Biochim Acta, 1984, 43(6), 829 - 33 Calibration of hybridoma antibody assays by polyclonal supernatants produced in vitro; Karsten U; Conventional antisera used as a positive control in antibody tests during hybridoma screening and processing can be replaced to advantage by supernatants of short term spleen cell cultures . Such cultures can easily be initiated from the same spleen cell suspension which is prepared in connection with a fusion experiment . Either supernatants of corresponding cultures from nonimmune animals or medium alone can serve as a negative control . In vitro produced polyclonal standards show very low background binding compared to antisera raised in vivo . They are convenient "ready-to-use" reagents with an antibody titer comparable to that expected in hybridoma culture fluids . There is no need for immunization and bleeding of separate animals . In addition, these supernatants provide an internal control of the immunization efficiency. Invest New Drugs, 1984, 2(2), 237 - 43 Toxicity of ASTA Z 7557 (INN mafosfamide) to normal- and leukemic stem cells: implications for autologous bone marrow transplantation; Hagenbeek A et al.; The activity of the in vitro active cyclophosphamide metabolite ASTA Z 7557 against pluripotent hemopoietic stem cells (CFU-S), in vitro myeloid precursor cells (CFU-C) and clonogenic leukemic cells (LCFU-S) was evaluated in a rat model for human acute myelocytic leukemia (BNML) . LCFU-S were most sensitive (D0 = 10.9 X 10(-6) M), followed by CFU-C (D0 = 16.4 X 10(-6) M), while CFU-S were least sensitive (D0 = 22.1 X 10(-6) M) . Per cell population there were considerable variations in response when identical drug concentrations were tested in different experiments under the same standardized conditions . Furthermore, the concentration of leukemic cells in a normal marrow cell suspension appeared to correlate with the cytotoxic action of the drug against leukemia . A decreased cytotoxicity was already observed in mixtures containing 1 leukemic cell per 10 normal marrow cells . The implications of these findings in the BNML model for human autologous bone marrow transplantation are discussed. Z Naturforsch {C}, 1984 Jan-Feb, 39(1-2), 136 - 40 Immune serum against anti-DNA-8-methoxypsoralen photoadduct; Zarebska Z et al.; Specific immune serum against photo-damaged DNA with the photoadducts of 8-methoxypsoralen (8-MOP) was obtained . The antigenic determinant is a polynucleotide chain with a mono-photoadduct: a coumarin moiety of psoralen linked through a cyclobutane ring to the 5,6-bond of thymine . The specific rabbit antiserum was used in the immunofluorescence method, for the detection of photodamaged DNA in the kinetoplasts and nuclei of unicellular organisms Crithidia luciliae, in the nuclei of snap-frozen tissue of mammals, and in human blood lymphocytes . Detection by the immunofluorescence method was limited by psoralen availability in situ; the psoralen concentration should be in the range 0.05-0.2 microgram/cm2 on specimens submitted to a topical application or about 1 microgram/ml in cell suspension . The long-wave ultraviolet light (UV-A) exposure dose applied to the nuclei should exceed 1 J/cm2. Arch Dermatol Res, 1984, 276(1), 27 - 32 Ultrastructural immunogold labelling of human Langerhans cells enriched epidermal cell suspension; Schmitt D et al.; Colloidal gold particles are well suited as markers in electron microscopy . Indirect immunogold staining was used to identify cell membrane antigens defined by monoclonal antibodies OKT6 and BL6 on human Langerhans cells (LC) in suspensions . Isolated epidermal cells were obtained by skin trypsinization and enriched or depleted in OKT6 positive on BL6 positive LC using the panning method: incubation of OKT6 or BL6 preincubated cells on immunoglobulin coated dishes . Indirect immunogold staining was then performed after prefixation in 2% paraformaldehyde . In LC enriched suspensions, only LC exhibited a specific membrane labelling with OKT6 or BL6 recognized by the presence of small evently distributed gold granules . Neither Birbeck granules, nor other cytoplasmic organelles, were labelled . No other epidermal cells were found positive . In LC depleted suspensions, no labelling was observed . Immunogold labelling on LC enriched suspensions after panning is now in progress for the qualitative evaluation and the quantitative analysis of cell surface constituents and antigens expressed by human dendritic epidermal cells. Infect Immun, 1984 Jan, 43(1), 314 - 9 Legionella pneumophila-induced blastogenesis of murine lymphoid cells in vitro; Friedman H et al.; Legionella pneumophilia antigen preparations, either killed whole cell vaccine, a soluble sonic extract, or a purified large-molecular-weight somatic antigen, stimulated blastogenic responses by splenocytes from both normal and Legionella-sensitized mice . Graded amounts of the bacterial preparations, when added to cultures of normal spleen cells, resulted in increased uptake of thymidine into cellular DNA, indicating that the preparations were mitogenic for normal mouse splenocytes . Spleen cells from mice injected with graded numbers of living bacteria showed blastogenic responsiveness to Legionella preparations generally at a higher level than spleen cells from normal animals . The heightened blastogenic response was mainly evident with spleen cells obtained from mice injected with living bacteria 2 to 3 weeks earlier . Splenocytes from mice infected with legionella less than 1 to 2 weeks or for more than 4 to 5 weeks responded generally similar to those obtained from uninjected mice, indicating that sensitization with living organisms had a relatively short duration . Spleen cell suspensions responding to the L . pneumophila antigens appeared to be mainly B-lymphocytes since cell suspensions from athymic nude mice deficient in T-cells responded as well as cells from conventional mice . Furthermore, passage of splenocytes over nylon wool columns to obtain B-cell-enriched preparations resulted in cell populations capable of responding to Legionella antigen . The cell fractions rich in T-cells were much less capable of responding to the Legionella antigens . In addition, treatment of spleen cell populations with antitheta serum plus complement failed to inhibit the blastogenic response, whereas the same spleen cell preparations treated with anti-mouse immunoglobulin serum plus complement markedly diminished blastogenic responsiveness, again consistent with the likelihood that B-lymphocytes were the major cell class responding to the Legionella preparations. Acta Otorhinolaryngol Belg, 1984, 38(6), 632 - 7 Analysis of lymphocytes in tonsils and blood from patients with chronic tonsillitis; Plum J et al.; A series of B, T and natural killer cell (NK) monoclonal antibodies was used to determine the distribution of lymphocyte subpopulations in cell suspensions obtained from tonsils of seventeen patients with chronic tonsillitis . The percentage of lymphocytes reacting with the monoclonal antibodies was determined by means of cytofluorometry . The majority of the tonsillar lymphocytes stained with the B-cell specific monoclonal antibody OKB-7 . The T lymphocytes were composed of a majority of OKT4+ lymphocytes . Only a minority of the lymphocytes stained with the NK cell specific antibody Leu-7, whereas Leu-11b+ lymphocytes were virtually absent . In ten out of the seventeen patients T lymphocytes were purified from the tonsils and the blood and studied for the presence of the following activation antigens: OKT9, OKT10 and anti-HLA-Dr . These antigens were not detected on the membrane of these lymphocytes . This indicates that T lymphocytes activated in vivo express these antigens in a low amount. Arch Immunol Ther Exp (Warsz), 1984, 32(6), 685 - 8 Enriched immune T cell suspension protects rabbits against infection with Treponema pallidum; Smogor W et al.; Four groups of rabbits were given intravenously (i.v.) enriched T or B lymphocytes derived from normal or immunized donor rabbits; 24 hrs later, all these animals were infected intradermally (i.d.) with T . pallidum in order to check their immune status . Only rabbits which received immune T cells showed a state of resistance to infection with T . pallidum, whereas recipients of lymphocytes of three other groups did not. Clin Exp Rheumatol, 1984 Jan-Mar, 2(1), 23 - 30 Proportional and functional studies of the infiltrating lymphocytes in the parotid gland of Sjögren's syndrome associated with rheumatoid arthritis; Ichikawa Y et al.; Lymphocyte subpopulations and functions were examined in the salivary (parotid) gland lymphocytes (SGL) obtained as a cell suspension from a patient with Sjogren's syndrome associated with rheumatoid arthritis, in comparison with peripheral blood lymphocytes (PBL) . Serial studies on the lymphocyte subsets in PBL using monoclonal antibodies to helper or suppressor T cell subsets (OKT4 or OKT8) demonstrated a decreased proportion of the OKT8 subset (OKT4/OKT8 ratio: 7.1-34.0) . Major infiltrating cells in the gland were surface immunoglobulin-bearing B cells, and 23-35% of the SGL were T cells by both the E-rosetting method and OKT3-monoclonal antibody reactivity . Moreover, OKT4/OKT8 ratios were definitely lower in the SGL (1.0 and 1.7) than those in the PBL of the patient . Mitogen-induced lymphocyte proliferative responses of the SGL were markedly diminished, although the possible participation of defective macrophages was considered . The autologous mixed lymphocyte reaction was low in both PBL and SGL . PBL of the patient showed normal proliferative responses to mitogens except for PWM stimulation . Suppressor effects of the SGL for the proliferative responses of autologous and allogeneic PBL were demonstrated . Con A-induced suppressor function was inducible in the SGL, whereas that function could not be demonstrated in the patient's PBL. Thymus, 1984, 6(5), 279 - 93 Macrophage subpopulations regulate intrathymic T-cell development . I: Ia-positive macrophages augment thymocyte proliferation; Zepp F et al.; The contribution of H2-Ia-positive thymic macrophages (Ia 1 thymic M phi) to intrathymic lymphopoiesis was investigated . An isolation method yielding cell suspensions highly enriched for Ia+ thymic M phi was performed . Cocultivation of these Ia+ thymic M phi with thymocytes showed that, while not affecting spontaneously proliferating thymocytes, the Ia+ thymic M phi strongly augmented the mitogen-induced proliferation of thymocytes by about 200% . This effect was dependent on the number of Ia+ M phi added as well as on the degree of thymocyte maturity: stronger augmentation occurred at higher concentrations of M phi and immature thymocytes showed highest susceptibility to the Ia+ thymic M phi-mediated effect . Cytochalasin B was employed to prove that cellular interaction is an important prerequisite for the proliferation amplifying effect of Ia+ thymic M phi . Additionally, humoral factors produced by Ia+ thymic M phi after induction with LPS are also involved in the described phenomenon . Furthermore, the use of interleukin preparations in the thymocyte-Ia+ M phi cocultures demonstrated that humoral factors support or probably regulate the interaction of these cells . The implications of these findings in view of the proliferation and differentiation events of thymocytes within the thymus are discussed. Biol Cell, 1984, 50(2), 121 - 6 Isolation of Kurloff cells by Percoll density gradient centrifugation . Protein labeling with 35S-methionine of these cells; Landemore G et al.; Large populations of splenic Kurloff (150 - 200 X 10(6) Kurloff cells) were obtained from estrogenized guinea pigs by isopycnic centrifugation in a Percoll solution of 1.085 g/ml starting density . The Kurloff cells settled at a buoyant density of about 1.100 g/ml . The purity of these cell suspensions reached 95%, as assessed by phase contrast microscopy and by specific staining . The viability assessed by Trypan blue exclusion test was also about 95% . Moreover, the good transmission electron microscopic appearance of these Kurloff cells and their ability to take up 35S-methionine in culture confirmed their physiological integrity . By autohistoradiography, this protein labeling was localized between the nucleus and the Kurloff body, and also on the Kurloff body itself . This data reinforces the hypothesis of de novo synthesis of the Kurloff body. Q J Exp Physiol, 1984 Jan, 69(1), 83 - 95 Epithelial cell volume regulation in hypotonic fluids: studies using a model tissue culture renal epithelial cell system; Simmons NL; The cultured renal epithelial cell line MDCK has been used in a study of cell volume regulation, emphasis being placed upon cell swelling in hypotonic media . MDCK cell volume was measured directly by electronic cell sizing using a Coulter counter in MDCK cell suspensions; this method gave comparable values for cell water when compared with those obtained using an intracellular space marker {14C}3-O-methyl glucose . MDCK cells behaved as perfect osmometers when suspended in hypertonic fluid (cell shrinkage) . Cellular swelling in hypotonic media, in certain conditions, was found to be less than expected for an ideal osmometer . Non-ideal swelling was found to be the result of a substantial loss of intracellular K+ (Cl-) due to a specific increase in membrane K+ permeability . The membrane channel mediating the increased net K+ loss was separate, by pharmacological identity, from the Na+-K+ pump, the diuretic-sensitive co-transport system and a Gardos-type channel inhibited by quinine . A role for increased Ca2+ influx mediating the increased K+ permeability is suggested by results from hypotonic exposure in nominally Ca2+-free solutions. J Cell Biol, 1984 Jan, 98(1), 173 - 8 Attractant-induced changes and oscillations of the extracellular Ca++ concentration in suspensions of differentiating Dictyostelium cells; Bumann J et al.; We used a Ca++-sensitive electrode to measure changes in extracellular Ca++ concentration in cell suspensions of Dictyostelium discoideum during differentiation and attractant stimulation . The cells maintained an external level of 3-8 microM Ca++ until the beginning of aggregation and then started to take up Ca++ . The attractants, folic acid, cyclic AMP, and cyclic GMP, induced a transient uptake of Ca++ by the cells . The response was detectable within 6 s and peaked at 30 s . Half-maximal uptake occurred at 5 nM cyclic AMP or 0.2 microM folic acid, respectively . The apparent rate of uptake amounted to 2 X 10(7) Ca++ per cell per min . Following uptake, Ca++ was released by the cells with a rate of 5 X 10(6) ions per cell per min . Specificity studies indicated that the induced uptake of Ca++ was mediated by cell surface receptors . The amount of accumulated Ca++ remained constant as long as a constant stimulus was provided . No apparent adaptation occurred . The cyclic AMP-induced uptake of Ca++ increased during differentiation and was dependent on the external Ca++ concentration . Saturation was found above 10 microM external Ca++ . The time course and magnitude of the attractant-induced uptake of external Ca++ agree with a role of Ca++ during contraction . During development the extracellular Ca++ level oscillated with a period of 6-11 min . The change of the extracellular Ca++ concentration during one cycle would correspond to a 30-fold change of the cellular free Ca++ concentration. Acta Pathol Microbiol Immunol Scand {A}, 1984 Jan, 92(1), 45 - 53 Dimethyl nitrosamine-induced proliferative and neoplastic lesions in the mouse liver characterized by histopathology and flow cytometric DNA measurements; Digernes V et al.; Thirty-one liver tumours induced in NMRI mice by treatment of the newborn animals with the carcinogen demethyl nitrosamine were examined histopathologically and by flow cytometric determination of nuclear DNA content . The tumours were classified as nodules of hyperplasia, adenomas or hepato-cellular carcinomas . Single cell suspensions from each tumour were analyzed by flow cytometry . The lesions consisted of cells with stemlines of low ploidy (2c and 4c) as compared to the high ploidy of the surrounding parenchymal cells (4c, 8c and 16c) . The hyperplastic nodules contained stemlines of both diploid and tetraploid DNA content, whereas the adenomas and most of the carcinomas were diploid . The possible occurrence of aneuploid cells in the lesions is discussed. Prog Clin Biol Res, 1984, 170, 613 - 28 Phototoxicity of brain tissue in hematoporphyrin derivative treated mice; Rounds DE et al.; Photoradiation therapy conditions which have been used to treat subcutaneous and breast tumors are lethal when applied to the head of mice . Treatment of control mice with laser light at 631 nm over an energy density range of 0-90j/cm2 had no measurable effect but mice photosensitized with 5 mg HPD/kg 72 hrs prior to laser treatment showed a threshold for brain damage at 56j/cm2, above which the mice developed cerebral edema and died . Laser treatment caused the same rate and magnitude of temperature rise in both control and HPD-photosensitized mice . Moreover, studies using mice whose brain temperature was kept below 37 degrees C during laser treatment showed a greater phototoxicity than mice without temperature regulation . Therefore, temperature rise in cerebral tissue was not associated with phototoxicity in the brain . In contrast the oxygen consumption rate in a brain cell suspension from an HPD-treated mouse was only 54% of that from a control mouse following treatment with laser light . This observation, when taken with supporting data from other investigations, suggests that one mechanism for the phototoxic response in brain tissue is oxygen deprivation resulting from mitochondrial damage. Urol Res, 1984, 12(2), 143 - 6 Cellular uptake of hematoporphyrin derivative in KK-47 bladder cancer cells; Hisazumi H et al.; The fluorescence emission spectra and degree of fluorescence polarization of hematoporphyrin derivative (HpD) have been investigated using HpD-containing KK-47 cells, PBS and cetyl trimethyl ammonium chloride (CTAC) micellar solutions . The fluorescence emission bands in the HpD-containing cell suspension were red-shifted and broadened as compared to those in the PBS solution . The degree of the polarization in the PBS and CTAC micellar solutions did not change with increasing incubation time, but in the cell suspension it increased temporarily and then decreased 4 h after incubation . These results suggest that HpD monomers and dimers may bind weakly to the outer cell membrane, and then slowly distribute throughout the intracellular loci in strong-binding form . In addition, the cellular uptake and/or binding loci of HpD were considered to be the mitochondria and nuclear membrane by subcellular fractionation and fluorescence microscopic studies. Biol Neonate, 1984, 46(5), 209 - 14 Action of polyamines on ribonucleic acid and protein synthesis during ontogeny of human fetal liver; Choudhury I et al.; A higher rate of RNA synthesis in human fetal liver cells was found during the early age of gestation, after a drop, it gradually increases to a maximum value between 18 and 22 weeks, followed by a sharp decrease at later period of gestation . Total polyamine content of fetal liver tissue shows a similar trend . However, when liver cell suspension was incubated with exogenous spermine, spermidine and putrescine there is a dose-dependent inhibition in RNA synthesis . Protein synthesis in human fetal liver cells was stimulated with lower doses of spermine, spermidine and putrescine and inhibited at higher doses . The optimum dose for stimulation and the degree of stimulation was, however, not the same for fetuses of different gestational ages. Acta Derm Venereol, 1984, 64(5), 421 - 4 Phenotypic characterization of skin-infiltrating cells in pagetoid reticulosis by monoclonal antibodies; Gonzalez M et al.; The immunological characterization of the infiltrating cells in a patient with a disseminated form of Pagetoid reticulosis (PR) was carried out-in histological section and cell suspensions--by means of a panel of monoclonal antibodies and classical markers (E-rosette and surface immunoglobulins (SIg} . Most of the infiltrating cells were seen to be mature T-lymphocytes with a suppressor/cytotoxic phenotype (T11+, T3+, T8+, T4-) . The results suggest that this variant of PR represents a special histological type of cutaneous T cell lymphoma. Thymus, 1984, 6(5), 335 - 45 Role of RNA in the induction of Thy-1+ phenotype on prothymocytes; Zemmour J et al.; Differentiation of spleen prothymocytes into Thy-1.2+ cells under the influence of thymosin requires transcription of DNA and translation of RNA, as demonstrated by the effects of inhibitors of DNA, RNA and protein synthesis . The lifespan of the induction message for this T cell differentiation appeared to be relatively short (30 to 60 min) in the presence of a reversible inhibitor of protein synthesis . When anisomycin, a protein synthesis inhibitor, was first introduced into the cell suspension, induction was suppressed but it was restored when actinomycin D, a RNA synthesis inhibitor, was added following anisomycin . By flow cytometry, the RNA content was slightly increased in the presence of thymosin and this increase was enhanced by the simultaneous addition of RNA and protein synthesis inhibitors. Folia Haematol Int Mag Klin Morphol Blutforsch, 1984, 111(1), 43 - 9 Antibodies and thermolabile opsonins in the phagocytosis of human red and white blood cells pretreated with formaldehyde; Nickolov C et al.; Erythrophagocytosis is conditioned by serum immunoglobulins . The extent of phagocytosis depends on the haematocrit of the red cell suspension pretreated with formaldehyde . The higher the haematocrit value, the lower will be the extent of phagocytosis . Phagocytosis of white blood cells pretreated with formaldehyde by granulocytes and monocytes is conditioned mainly by a thermolabile fraction of the serum, probably the complement. Pharmacol Res Commun, 1984 Jan, 16(1), 101 - 7 Inhibiting effect of levamisole on superoxide production from rat mast cells; Schinetti ML et al.; The aim of the present study was to test whether levamisole acts as a superoxide scavenger . The drug was incubated at four different concentrations (range 1, 5, 10, 20 micrograms/ml) with purified rat mast cells which were then induced to generate superoxide ions, by challenge with compound 48/80 (1 microgram/ml) . Ten minutes preincubation with the drug completely abolished superoxide ions production . Addition of levamisole to the cell suspension simultaneously with the releaser caused full inhibition of O2(-) generation at the lowest dose, while higher doses failed to suppress 48/80 induced O2(-) generation . In a cell-free superoxide-generating system, like xanthine-xanthine oxidase, levamisole did not act as a superoxide scavenger at any of the doses tested. Histochemistry, 1984, 80(1), 79 - 84 A reliable method with good cell preservation for the demonstration of peroxidase activity in human platelets and megakaryocytes; Heynen MJ et al.; We have tried to improve existing methods for demonstration of platelet peroxidase (PPO) in human platelets and megakaryocytes by introducing a fixation of 0.1% glutaraldehyde prior to incubation in the DAB medium . This prefixation with low concentration of glutaraldehyde preserves excellent morphological detail and does not inhibit PPO activity . All 23 platelet-rich plasma samples show PPO reaction product in the dense tubular system after incubation in DAB medium with 0.003% H2O2 . When 0.01% H2O2 is used in excessive DAB medium, PPO activity can also be demonstrated in platelets and megakaryocytes of bone-marrow cell suspensions . This method can be used for the identification of megakaryoblasts in acute non-lymphocytic leukemia, myelodysplastic syndromes and in blastic crisis of chronic myeloid leukemia . PPO cytochemistry can be combined with postfixation in a OsO4-ruthenium red mixture . This method reveals alpha-granules, dense bodies, microtubuli, glycogen, mitochondria, dense tubular system and invaginated membrane system in the same platelet and is useful for investigation of platelet ultrastructure. Cytometry, 1984 Jan, 5(1), 71 - 80 Flow cytometric analysis of DNA aneuploidy in primary and metastatic human solid tumors; Frankfurt OS et al.; DNA histograms were measured by flow cytometry for 656 human solid tumors (365 primary and 291 metastatic) . The proportion of aneuploid cells in cell suspensions obtained by mechanical disaggregation was significantly higher than those obtained after enzymatic disaggregation (collagenase + DNAse) of the same tumor . A strong correlation was observed between the values of DNA-indices measured after staining with propidium iodide and with 4',-6-diamidino-2-phenylindole (r = 0.97) . Aneuploid cells were observed in 430 tumors (66%); 30 of these had two aneuploid stemlines, and two had three aneuploid stemlines . The overall frequency of aneuploidy was 61% among primary and 71% among metastatic tumors . The median value of the DNA index was 1.67 for 224 primary aneuploid tumors and 1.68 for 206 metastatic aneuploid tumors . For most diseases, the largest proportion of aneuploid primary and metastatic tumors had DNA-indices in the hypertriploid region . No major differences in frequency and degree of aneuploidy was observed between primary and metastatic tumors . For carcinomas of the bladder and prostate, frequency of aneuploidy was higher among poorly differentiated, than among moderately and well-differentiated tumors . For carcinomas of the breast and for sarcomas, tumors with DNA-indices of greater than 2.0 were observed mostly in the poorly differentiated group . For patients with carcinomas of the bladder and prostate most tumors at earlier stages of disease were diploid; whereas most tumors at later stages of disease were aneuploid . For patients with carcinomas of the ovary, colon, and kidney, no relationship between stage of disease and aneuploidy was evident. Acta Histochem, 1984, 75(2), 175 - 82 Dipeptidyl peptidase IV and alpha-naphthylacetate esterase in human T lymphocytes: cytochemical and biochemical investigations; Schon E et al.; Dipeptidyl peptidase IV (DP IV) activity of human lymphocytes was measured using biochemical assays of cell suspensions and enzyme cytochemical staining of smears from capillary blood and mononuclear cells (MNC) . The hydrolysis rate of Gly-Pro-pNA in suspensions of MNC correlates well with the number of DP IV reactive cells as determined by cytochemical staining . MNC from healthy volunteers were shown to contain 44 +/- 10% lymphocytes reactive for DP IV . Using preparations of T lymphocytes and adherent MNC it was shown that DP IV is specific for T lymphocytes . About 60% of T lymphocytes contain DP IV and 94% of DP IV reactive cells form rosettes with sheep erythrocytes . Parallel staining for DP IV and unspecific acid alpha-naphthylacetate esterase (ANAE) yielded nearly the same figure of cells stained for ANAE in a dot-like pattern (50 +/- 10% MNC) as was observed for DP IV . Correlation of both markers indicates that DP IV expressing lymphocytes presumably represent that subpopulation of TM cells which is characterized by a dot-like reaction pattern of ANAE. Immunogenetics, 1984, 20(4), 359 - 71 AT-1.1: a thymus-specific alloantigen of chickens; Waytes AT et al.; A thymocyte-specific alloantigen, designated AT (avian thymus)-1.1, has been detected in Cornell C strain (CS) and Obese strain (OS) chickens, the latter being a strain derived from CS which develops a spontaneous form of autoimmune thyroiditis (SAT) . Antisera specific for this antigen were developed first in a turkey immunized with thymocytes from an OS chicken and, later, in AT-1.1-negative CS chickens immunized with AT-1.1-positive thymocytes . AT-1.1 was detected in 50-70% of cells in a thymus cell suspension, but was not seen on peripheral blood lymphocytes, erythrocytes, or cells from bursa, spleen, kidney, liver, or brain . It was present on thymocytes of chickens at all ages tested, from 1 day to 6 months of age . AT-1.1 was not detected in six chicken lymphoid tumor cell lines tested, and birds expressing it were found to be negative for the presence of Marek's disease viral antigens . Pedigree studies on 287 (OS X CS)F2 chickens demonstrated that AT-1.1 is expressed in a dominant or codominant manner, and the gene coding for this antigen was not linked to the beta (major histocompatibility) complex . The genetics and tissue distributions of AT-1.1 indicate that it differs from thymus cell surface antigens, avian or mammalian, previously described. Virchows Arch B Cell Pathol Incl Mol Pathol, 1984, 46(3), 215 - 28 Distribution of dendritic reticulum cells in follicular lymphoma and reactive hyperplasia . Light microscopic identification and general morphology; Peters JP et al.; Reactive and neoplastic follicles in lymph nodes showing changes of (1) follicular hyperplasia and (2) follicular lymphoma were examined for the presence of dendritic reticulum cells (DRC) . These cells could be identified under the light microscope after comparing electron microscopical sections with subsequent 1 micro sections of reactive germinal centres . Quantitative light microscopical evaluation showed that DRC, both mononuclear and binuclear forms, were less numerous in neoplastic follicular structures than in reactive follicles . Before determining the frequency of binucleated DRC in follicular tissue their morphology was studied first in cell suspensions . DRC isolated by enzymatic treatment of tonsils and reactive lymph nodes were morphologically identical and contained one, or at most two, nuclei arranged in a typical doublet formation . Stereological calculations - made on three dimensional models of nuclear complexes prepared from serial tissue sections - indicated that 51 to 68% of DRC in reactive germinal centres were binucleated, whereas in neoplastic follicles this figure is 18 to 23% . The multinucleated giant cell forms of DRC described by others result from complex formation with other DRC or lymphoid cells . The smaller number of DRC and the lower frequency of binucleated DRC in follicular lymphomas suggest that differentiation of DRC from stromal cells is less complete in these neoplasms . The ability to identify DRC reliably by light microscopy offers a new means to define the difference in frequency of DRC . This may be of practical value in distinguishing reactive germinal centres from neoplastic follicles. Drug Metab Dispos, 1984 Jan-Feb, 12(1), 25 - 34 7-ethoxycoumarin O-deethylation activity in viable basal and differentiated keratinocytes isolated from the skin of the hairless mouse; Pohl RJ et al.; Epidermal cells in suspension were prepared from the skin of hairless mice by digestion of skin strips with pronase . The viability of cells in such suspensions was routinely greater than 75% . Fractions enriched in different cell types were prepared from the original cell suspensions using metrizamide gradients and elutriation techniques . These fractions were studied histologically and enzymically . The cells of greater size both were more differentiated and had higher xenobiotic metabolizing enzyme activities . Also increasing in parallel with cell size were parameters such as protein to DNA ratios . Lowest in all respects were basal cells (size, enzyme activities, protein/DNA ratios, etc.) . The present techniques seem superior to previously described methods for isolating skin cells for study of xenobiotic metabolisms and possible distribution of these metabolisms in different cell types. Vet Med Nauki, 1984, 21(6), 11 - 7 {Cultivation of the transmissible gastroenteritis virus in a continuous cell line}; Belopopska P et al.; Cell cultures of the permanent cell line SPEV to which the transmissive gastroenteritis virus had already been adapted were used to culture the virus and carry out the virus-neutralization test . Use was made of a cell suspension of a variable density--300 and 500 thou cells per cm3 . Both variants of the cell suspension were comparatively studied in terms of growth, the production of a monolayer, susceptibility to infection, and titer of the virus obtained, using 4 test tubes with the virus at various rates of dilution which were kept under observation daily, keeping a record of the infected and noninfected cell cultures . The amount of the virus was determined by titration . It was found that the monolayer was produced more rapidly in the suspension containing 500 thou cells/cm3 . In that case infection could be performed at the 24th hour . The cytopathic effect was more pronounced, and the titer of the virus obtained was higher . Successful attempts were made with the virus-neutralization test with the infection of the cell cultures in suspension . Thus, the entire procedure was shown to be labour-saving as the time for investigation of the sera was shortened. Clin Chim Acta, 1983 Dec 30, 135(3), 253 - 62 Effect of parathyroid hormone and uremic sera on the autoagglutination and sedimentation of human red blood cells; Earon Y et al.; Parathyroid hormone (PTH) caused a dramatic acceleration of erythrocyte sedimentation rate (ESR) . This effect was calcium dependent and was partially reversed by verapamil . It was not mimicked by 5 mumol/l calcium ionophore A-23187 . Following the removal of PTH from the cell suspension the ESR returned to normal . PTH also caused haemagglutination, the reaction was Ca2+ dependent, pH dependent and was partially reversed by verapamil . High levels of Ca2+ ionophore A-23187 mimicked this phenomenon . Magnesium ions even at concentrations of 5 mmol/l did not replace Ca2+, while Ca2+ at concentrations of 3 mmol/l and above caused haemagglutination . The glycolytic inhibitor NaF at levels of 1 mmol/l did not inhibit haemagglutination . The polyamines pertusin and spermidin, prostaglandins PGE2 and PGF, and the calcium hormone calcitonin, did not reproduce the PTH effect . Dialysate from serum of patients with chronic renal failure and hyperparathyroidism caused haemagglutination, while dialysate from patients with chronic renal failure following parathyroidectomy and normal individuals did not cause this phenomenon . It seems that abnormal erythrocyte behaviour seen in patients with chronic renal failure is caused by PTH which leads to modified Ca2+ metabolism in these cells. J Biol Chem, 1983 Dec 25, 258(24), 14856 - 60 Metabolism of alanylalanyl-S-{N-(2-thioethyl)}aminopyridine-2, 6-dicarboxylic acid}cysteine by suspensions of Escherichia coli; Perry D et al.; The attachment of 4-{N-2-(mercaptoethyl)}aminopyridine-2,6-dicarboxylic acid (MEPDA) to AlaAlaCys through a disulfide bond to the cysteine residue has been described (Boehm, J . C., Kingsbury, W . D., Perry, D., and Gilvarg, C . (1983) J . Biol . Chem . 258, 14850-14855) . The peptide disulfide showed enhanced growth inhibitory properties in Escherichia coli compared to the free sulfhydryl compound . Genetic evidence was presented to show that this side chain-modified peptide utilizes the oligopeptide transport system to gain entry to the cell . Following transport of the peptide, MEPDA is liberated by disulfide exchange reactions with sulfhydryl-containing components of the cell pool . In this paper, we examine in more detail the metabolism of this peptide . Using gel filtration chromatography to examine filtrates from cell suspensions incubated with the peptide, it was shown that loss of the peptide from the medium is accompanied by a corresponding increase in a component having the properties of MEPDA . The release of sulfhydryl groups from the peptide by cell suspensions could be monitored by Ellman's reagent and was found to be dependent upon peptide transport . Following cleavage of the disulfide bond, MEPDA is able to cross the cytoplasmic membrane and exit from the cell as a relatively lipophilic uncharged metal chelate. Int J Cancer, 1983 Dec 15, 32(6), 667 - 74 Characterization of malignant and non-neoplastic cell phenotypes in highly malignant non-Hodgkin lymphomas; Porwit-Ksiazek A et al.; Malignant and non-neoplastic cells in 38 cases of highly malignant non-Hodgkin lymphomas: 3 centrocytic anaplastic, 18 centroblastic, 13 immunoblastic and 4 lymphoblastic (according to the Kiel classification) were immunophenotyped in cryosections and cell suspensions by means of monoclonal antibodies . Additionally, cell cycle analysis on cell suspensions was performed by DNA flow cytofluorometry . In 33 (87%) lymphomas the malignant cells expressed monoclonal surface immunoglobulin (Ig), which indicated B-cell origin of tumors . In 7 of the 19 B-cell lymphomas tested by the peroxidase-antiperoxidase method, cytoplasmic Ig was found . Four lymphomas were of T-cell and one of non-B/non-T-cell origin . In II B-cell and 2 lymphoblastic non-B-cell tumors, common acute lymphoblastic leukemia antigen (CALLA) was found . In 25 of 30 studied NHL the malignant cells expressed receptor for transferrin and in 19 of 28 cases a high percentage of cells in S-phase (greater than 10.85%) was found . Number and distribution as well as type of non-B-cells infiltrating B-cell-derived lymphomas varied considerably from case to case . Among these cells Leu 3+ (T helper/inducer) cells predominated . Leu 2+ (T suppressor/cytotoxic) and Leu 7+ (natural killer and killer) cells constituted less numerous groups . Correlation of cytodiagnostic analyses with clinical observations indicates that high content of infiltrating T cells may be a favorable prognostic feature in highly malignant B-cell lymphomas. Xenobiotica, 1983 Dec, 13(12), 743 - 53 Dynamics of xenobiotic metabolism by isolated rat hepatocytes using a multichannel perifusion system; Orton TC et al.; The multichannel perifusion system in recirculating and non-recirculating (single-pass) mode has been used to monitor the rate of oxidative metabolism of three model substrates--7-ethoxycoumarin, dichloronitroanisole and aldrin . With control hepatocytes, the rate of de-ethylation of 7-ethoxycoumarin derived from recirculating mode was essentially similar to the rate obtained with conventional flask-incubated cell suspensions . The formation of 7-hydroxycoumarin glucuronide and sulphate by hepatocytes exposed to 7-ethoxycoumarin demonstrated the retention of conjugative ability of cells in the perifusion system . The rate of demethylation of dichloronitroanisole to dichloronitrophenol was low whilst aldrin epoxidation to dieldrin was rapid using control hepatocytes in recirculating mode . The inductive effect of phenobarbitone on hepatic mixed-function oxidases was demonstrated by a marked increase in the rate of 7-ethoxycoumarin (nine-fold) and dichloronitroanisole (64-fold) dealkylation by hepatocytes from phenobarbitone-treated animals in recirculating mode . The rate of substrate oxidation by hepatocytes perifused in the recirculating and the single-pass mode were the same . With dichloronitroanisole as substrate and a single-pass mode, the rate of dichloronitrophenol formation declined rapidly on perifusion with substrate-free medium and rapidly re-attained steady state on re-introduction of the substrate; the presence of metyrapone effectively inhibited dichloronitroanisole metabolism . The perifusion system is recommended for the study of the dynamics of xenobiotic metabolism by isolated mammalian hepatocytes. J Biochem Biophys Methods, 1983 Dec, 8(4), 275 - 89 A study of cell electrophoresis as a means of purifying growth hormone secreting cells; Plank LD et al.; Growth hormone secreting cells of the rat anterior pituitary are heavily laden with granules of growth hormone and can be partially purified on the basis of their resulting high density . Two methods of preparative cell electrophoresis were investigated as methods of enhancing the purification of growth hormone producing cells: density gradient electrophoresis and continuous flow electrophoresis . Both methods provided a two- to four-fold enrichment in growth hormone production per cell relative to that achieved by previous methods . Measurements of electrophoretic mobilities by two analytical methods, microscopic electrophoresis and laser-tracking electrophoresis, revealed very little distinction between unpurified anterior pituitary cell suspensions and somatotroph-enriched cell suspensions . Predictions calculated on the basis of analytical electrophoretic data are consistent with the hypothesis that sedimentation plays a significant role in both types of preparative electrophoresis and the electrophoretic mobility of the growth hormone secreting subpopulation of cells remains unknown. In Vitro, 1983 Dec, 19(12), 919 - 28 Establishment of two nonmetastasizing and one metastasizing rat mammary carcinoma cell lines; Ghosh SK et al.; Two continuous rat mammary tumor cell lines have been established in culture from the lymphogenously metastasizing rat mammary carcinoma TMT-081 and one from the nonmetastasizing MT-100 and some of their in vitro and in vivo characteristics studied . Cell line TMT-081-MS was established as a free-floating cell suspension from the metastasis-free spleen of a rat bearing TMT-081 in the ascites form and is characterized by a high level of mammary tissue specific antigen (MTA), an antigen present on lactating or hormonally stimulated rat mammary tissues but not detected on normal mammary tissue . This line metastasizes in the syngeneic host but is rejected by the nude mouse without metastases . Cell line TMT-081-NM is a line derived from the ascites of a rat also bearing TMT-081 ascites . Cell line MT-100-TC is a line derived from the ascites of a rat bearing the ascites form of MT-100 . Neither TMT-081-NM nor MT-100-TC has ever shown metastases in the syngeneic host but they are lethal; in the nude mice they grow rapidly, are lethal, and sometimes show hematogenous metastases . Both grow in small clusters and show a low level of MTA . These cell lines have been in continuous culture for a year and have proliferated and maintained their individual in vitro and in vivo growth characteristics during more than 100 consecutive subcultivations. Am J Vet Res, 1983 Dec, 44(12), 2379 - 84 Isolation and partial characterization of equine alveolar macrophages; Dyer RM et al.; A device was constructed from an equine nasogastric tube, polyethylene tubing, and a 3-way stopcock and used to lavage the lungs of anesthetized ponies . The technique was safe and atraumatic in that 6.4 to 19.7 X 10(7) purified alveolar macrophages were removed from the lungs without harm to the ponies or contamination of the samples with blood . Studies of these highly purified cell suspensions revealed a mean viability of 85% as assessed by eosin dye exclusion with a mean recovery (+/- SD) of 12.5 +/- 4.8 X 10(7) pulmonary alveolar macrophages/pony. J Urol, 1983 Dec, 130(6), 1060 - 2 Renal cell carcinoma and the clonogenic assay; Fleischmann J et al.; The clonogenic assay is an in vitro chemosensitivity test performed on tumor specimens and has had limited success in predicting or confirming patient response to chemotherapy . We investigated this assay system, using a 1-hour method, in 37 renal cell carcinoma specimens to determine its clinical usefulness . These specimens also were graded independently by a pathologist with respect to cell type, mitotic figures and degree of differentiation . Only 22 specimens formed at least 50 colonies per 500,000 cells plated and few specimens displayed any chemosensitivities . Marked variations of colony counts among duplicate controls or drug-treated samples demonstrated further the unreliability of the assay . Of several factors responsible for the poor performance of the assay the 2 outstanding problems were losses of clear cells in variable amounts (unique to renal cell carcinoma), and the inability to generate and maintain single cell suspensions . Pathologic correlations confirmed that predominantly clear cell carcinomas did not form colonies as well as granular cell carcinomas . Owing to these problems in its present form the clonogenic assay is not useful clinically and is unsuited particularly for renal cell carcinoma. Chem Biol Interact, 1983 Dec, 47(3), 277 - 87 Glucuronidation and sulfation of p-nitrophenol in isolated rat hepatocyte subpopulations . Effects of phenobarbital and 3-methylcholanthrene pretreatment; Tonda K et al.; Parenchymal cells, isolated from untreated (control), phenobarbital(PB)-or 3-methylcholanthrene(3-MC)-treated rats, were separated into four subpopulations according to cell density, and glucuronidation and sulfation of p-nitrophenol (PNP) in the hepatocyte subpopulations were investigated . PB enhanced the glucuronidation almost 2-fold but not the sulfation, while 3-MC enhanced both glucuronidation (3-fold) and sulfation (2-fold) in the original cell suspensions . Some gradation trends were found in the conjugation activities among the hepatocyte subpopulations: In the control experiment, the extent of glucuronidation in four subpopulations was virtually the same but sulfation in high-density hepatocytes was slightly higher than in low-density ones . Both glucuronidation and sulfation were higher in low-density hepatocytes from PB-treated rats, though the gradation was very modest . Glucuronidation and sulfation tended to be slightly higher in middle-density hepatocytes in the 3-MC experiment . However, no definite correlation in conjugation activities vs . cell density, like those seen in cytochrome P-450s vs . cell density in the hepatocytes isolated from PB-treated rats, were found in the subpopulations from control or inducer-treated rats . Simultaneous studies on acetylation of p-aminobenzoic acid (PABA) revealed that the activities in the subpopulations were virtually the same and the inducers had little influence on the activity. J Immunol, 1983 Dec, 131(6), 2719 - 25 Peroxidase-positive mononuclear leukocytes as possible precursors of human dendritic reticulum cells; Parwaresch MR et al.; In this report, we provide evidence that suggests the dendritic reticulum cells (DRC) occurring in germinal centers of lymphatic follicles originate from a distinct endogenous peroxidase-positive mononuclear blood cell subset . The new monoclonal antibody Ki-M4 showed a highly restricted reactivity, tested by immune histochemistry, being confined to DRC, lining cells of lymph node sinuses, and to 0.001% of nonadherent mononuclear blood cells separated at a density of 1.077 g/ml; the latter exhibited endogenous peroxidase activity in cytoplasmic granules . Such granules being specific for myelomonocytic cells implies that DRC may derive from a committed nonadherent subpopulation of this cell line, which in turn originates from bone marrow . The Ki-M4-reactive antigen was found to be destroyed by the majority of fixatives and to resist 4% paraformaldehyde for 10 min and cold acetone for 30 sec . In cell suspensions from human tonsils, Ki-M4 showed strong reactivity with the outer surface of DRC plasma membrane . This observation demonstrates the possibility of using Ki-M4 to separate DRC from cell suspensions in functional tests. Blood, 1983 Dec, 62(6), 1289 - 96 Immunohistologic study of bone marrow involvement in B-chronic lymphocytic leukemia; Pizzolo G et al.; Bone marrow trephine biopsies from 17 patients with B-chronic lymphocytic leukemia (B-CLL) were studied by immunohistologic techniques in order to investigate the cellular phenotypes of both neoplastic (B-lymphoid) and reactive (T-lymphoid) infiltrates . For this purpose, several heteroantisera and monoclonal antibodies against human Ig isotypes, HLA-DR antigens, and T-cell subpopulations were used in immunofluorescence . The findings were analyzed in relationship to the histologic pattern of involvement, as well as to the immunologic data of cell suspensions from peripheral blood . In all cases, the dominant lymphoid population within the bone marrow infiltrates showed identical phenotypic characteristics of B-CLL cells from the blood (HLA-DR+, mu +, most frequently delta +, kappa +, or lambda +, and weakly RFA-1+) . The infiltration by these malignant B cells was diffuse in 5 cases and nodular plus interstitial in 12 . The number of T cells (UCHT1+, RFA-1+, mu) was variable (5%-25%) in the different samples, but the values were high when compared to the proportion of T cells in normal bone marrow and in the blood of most patients studied . Furthermore, a clear predominance of T cells exhibiting the inducer phenotype (Leu-3+) was observed in all bone marrow samples, which is in contrast with the findings from peripheral blood, where T cells with the suppressor/cytotoxic phenotype (Leu-2+) were dominant . These data suggest a different blood and tissue distribution of inducer and suppressor/cytotoxic cells in B-CLL, which may have important pathophysiologic significance. Cell Calcium, 1983 Dec, 4(5-6), 499 - 510 Properties of the CA2+-activated K+ conductance of human red cells as revealed by the patch-clamp technique; Grygorczyk R et al.; Application of Ca2+ to the inner surface of red-cell membranes activates unitary currents that can be measured in cell-attached and cell-free membrane patches . Ca2+ can be replaced by Pb2+ to activate the single channels . In addition to internal Ca2+ external K+ has to be present . The channels are preferentially permeable to K+ with a selectivity ratio PK:PNa of about 15:1 as estimated from measurement of reversal potentials . The dependence of channel activity on Ca2+ is compatible with the conception that the binding of two Ca2+ is necessary to open a single channel . Both the channel activity and the single-channel conductance exhibit inward rectification . External and internal Na+ inhibit the K+ currents . The reported results suggest that the unitary current events are responsible for the Ca2+-dependent K+ permeability known from measurement on cell suspensions . Therefore, comparison of the two techniques allows calculation of the number of K+ channels per red cell, which on average is about 10. Biol Reprod, 1983 Dec, 29(5), 1172 - 8 Studies with purified immature porcine Leydig cells in primary culture; Bernier M et al.; The steroidogenic capacity of purified immature porcine Leydig cells in culture was studied over several days . The cells were obtained by fractionating crude testicular interstitial cell suspensions on a discontinuous Percoll gradient (d = 1.037, 1.042, 1.052, 1.098 g/ml), and characterized by specific binding of 125I-human chorionic gonadotropin (hCG), testosterone (T) and cyclic adenosine 3':5'-monophosphate (cAMP) production in response to hCG, and the enzymatic determination of delta 5-3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) activity . The Leydig cells were recovered in a density band between 1.052-1.068 g/ml and grown in a chemically defined medium (Mather et al., 1981) . In the absence of hCG, T production was low throughout the 6 days of culture . However, in response to hCG (10 mIU/ml), the cultured Leydig cells showed a progressive increase in T synthesis, which reached a maximum at Days 3-4 . 8-Br-cAMP (1 mM) induced a comparable rise in T production to that obtained with hCG throughout the culture period . In contrast, 8-Br-cAMP induced a near maximal increase in dehydroepiandrosterone (DHEA) production from Day 1 . This paper demonstrates that purified immature porcine Leydig cells in primary culture are a valuable model to study the ontogeny of Leydig cell function. Ann Rheum Dis, 1983 Dec, 42(6), 693 - 8 Decreased T-suppressor cell activity in rats with adjuvant arthritis; Binderup L; Concanavalin-A-induced T-suppressor cell activity was decreased in spleen cell suspensions from Lewis rats with adjuvant arthritis . This decreased activity was evident on day 10 after the induction of the disease, just before the development of the polyarthritic lesions, and persisted during the period of active inflammatory and immunological disease . The extent of the impairment of T-suppressor cell activity was positively correlated with the severity of the arthritic lesions . Removal of phagocytic cells prior to induction of T-suppressor cells abolished the observed decrease in suppressor cell activity . It is suggested that this model may be of value for the investigation of suppressor cell function in immunologically mediated disorders. Gann, 1983 Dec, 74(6), 870 - 7 Establishment of an alpha-fetoprotein-producing human gastric carcinoma in nude mice; Ezaki T et al.; An alpha-fetoprotein (AFP)-producing human gastric carcinoma was transplanted into BALB/c-nu/nu nude mice . The original tumor tissue had been obtained by gastrectomy from a 72-year-old patient with gastric carcinoma . The tumor had been transplanted serially (20 passages) in nude mice . The transplantability was 100% . The doubling time of the tumor ranged from 5.6 days to 11.2 days . AFP appeared in the serum of nude mice 3 to 4 weeks after subcutaneous (sc) transplantation and 6 weeks after intraperitoneal (ip) transplantation of the tumor cell suspension prepared from sc transplanted tumors . A positive correlation was observed between serum AFP level and tumor size . Serum AFP level of mice given ip transplantation increased as a function of time after transplantation . AFP was stained positively by an immunochemical technique in the original and transplanted tumors and was located in the cytoplasms of the tumor cells . The histology of the original tumor was retained . The malignant potential of these transplanted tumor cells was expressed as carcinomatous peritonitis and liver and/or lung metastases. Brain Res, 1983 Dec, 313(2), 275 - 80 Lucifer yellow uptake in developing rat retina: selective staining of horizontal cells; Sarthy PV et al.; We have examined the uptake of Lucifer yellow CH by developing rat retina . We find that selective dye uptake occurs in retina incubated in vitro in the absence of external Ca2+ . The pattern of uptake appears to depend on the developmental stage examined . Although little uptake is seen before postnatal day 5, between days 6 and 9, the dye selectively stains putative horizontal cell bodies and their process . Later, other cell bodies located deeper in the INL begin to show staining until day 21, when the uptake pattern becomes analogous to that seen in adult retina . By nearest neighbor analysis of labeled cell bodies in wholemounts of D-9 retina, we have shown that the labeled cells are distributed in a quasi-regular mosaic in the retina . Upon proteolytic dissociation of labeled retina, individual cells with Lucifer yellow fluorescence could be readily identified in the cell suspensions. Scand J Immunol, 1983 Dec, 18(6), 485 - 93 Leu 7+ (HNK-1+) cells . I . Selective compartmentalization of Leu 7+ cells with different immunophenotypes in lymphatic tissues and blood; Porwit-Ksiazek A et al.; In the present immunohistochemical studies, Leu 7+ (HNK-1+, human natural killer and killer) cells were found to occupy preferentially germinal centres of follicles in lymph nodes and tonsils . Leu 7+ cells were also present in germinal-like zones of spleen follicles and in mantle zones of hyperplastic thymus follicles and varied in localization in lymph nodes involved in different types of follicular centre cell-derived malignant lymphomas . Most of the Leu 7+ cells in the follicles expressed the Leu 3 (helper/inducer) marker . Double staining studies of tonsil sheep erythrocyte-rosetting and peripheral blood mononuclear cell suspensions showed that two main, mutually complementary, subpopulations of Leu 7+ cells could be distinguished in both cases, namely Leu 7+/Leu 4+ (subdivided into Leu 2+ (suppressor/cytotoxic) and Leu 3+) and Leu 7+/Leu 4-, including mostly cells with OKM 1 (myelomonocytic) characteristics . Thus, in the tonsil cell suspension the cells with Leu 7+ Leu 3+/OKM 1- immunophenotype strongly predominated, whereas among peripheral blood mononuclear cells Leu 7+Leu 2+/OKM 1- and Leu 7+/OKM 1+ immunophenotypes were mostly observed. J Immunol, 1983 Dec, 131(6), 2670 - 4 Alloantigens placed into the anterior chamber of the eye induce specific suppression of delayed-type hypersensitivity but normal cytotoxic T lymphocyte and helper T lymphocyte responses; Niederkorn JY et al.; Intracameral inoculation of allogeneic B16F10 melanoma cells (C57BL/6) into LP/J mice resulted in progressively growing intraocular tumors and impaired delayed-type hypersensitivity (DTH) reactivity . Additional experiments showed that DTH responses were specifically down-regulated by splenic T suppressor cells . By contrast, subcutaneous inoculation of B16F10 melanoma cells induced significant DTH responses to the alloantigens expressed on the tumor cells and stimulated brisk rejection of the subcutaneously injected tumor cells . In spite of the T suppressor cell inhibition of DTH reactivity, significant cytotoxic T lymphocyte activity could be demonstrated in lymphoid cell suspensions from hosts harboring allogeneic intraocular tumors . The demonstrated cytotoxic T lymphocyte activity is particularly noteworthy because it occurs in the face of severely suppressed DTH responsiveness and thus implies that the intracameral presentation of alloantigens evokes a precise immunoregulatory process that selectively and concomitantly modulates specific cellular immune components; one immune process (cytotoxic T lymphocyte function) is stimulated whereas the other (DTH responsiveness) is down-regulated. Endocrinology, 1983 Dec, 113(6), 2120 - 8 Heterogeneous luteinizing hormone and follicle-stimulating hormone storage patterns in subtypes of gonadotropes separated by centrifugal elutriation; Childs GV et al.; The application of centrifugal elutriation to the separation of pituitary cells has produced a fraction that is enriched with LH and FSH gonadotropes . In this study, stains were performed on serial sections of fractions taken from six elutriation experiments with 1:10,000-1:30,000 anti-bLH beta or 1:2,000-1:8,000 anti-hFSH beta and the avidin-biotin-peroxidase complex technique . Over 900 serially sectioned gonadotropes were analyzed . In the initial cell suspensions, 59.6% of the gonadotropes contained both LH and FSH; 18% contained LH, and 23% contained FSH . Fewer than 3% contained ACTH . The elutriation fractions contained several subtypes of gonadotropes . A few small (8 micron), poorly granulated LH or FSH cells were eluted with the smallest cells (10-12%) at flow rates of 15.7 ml/min . Medium sized gonadotropes (10-10.5 micron) that eluted at flow rates of 19.8-30.5 ml/min were infrequent (3-6%) and resembled the larger gonadotrope . An analysis of serially sectioned fields showed that only 15.2%-22% of the small and medium sized gonadotropes contained both LH and FSH, whereas 30-40% contained only LH and 46-50% stored only FSH . The gonadotrope-enriched fraction was eluted at 37-39.5 ml/min; 78% of these gonadotropes (diameter, 14-15 micron) contained both LH and FSH, 10% contained only LH, and 12% contained FSH . Finally, large cells (diameter, 15-16 micron) that contained FSH only were found in the Wash fraction . These studies demonstrate that smaller gonadotropes tend to store only one of the hormones whereas most of the larger cells either store LH and FSH together or FSH alone . These heterogeneous storage patterns may correlate with studies by others who measured different responses to GnRH in gonadotropes separated by size on a unit gravity sedimentation gradient . They may also reflect different secretory phases of gonadotropes from the mixed group of cycling female rats. Endocrinol Jpn, 1983 Dec, 30(6), 769 - 75 An ecto-ATPase of thyroidal cell membrane; Yoshimura Y et al.; The isolated cells were obtained from hog thyroid glands treated with dispase . More than 95% of the cells obtained were intact and viable immediately after preparation, and the cell viability did not change during incubation in the experimental conditions . ATP added to the external medium of whole cell suspensions was hydrolyzed in the presence of various divalent cations, especially Mg, and the rate of hydrolysis of ATP was not significantly different between the Mg-ion system and the completed ion system (Mg+Na+K) . When whole cell suspensions were disrupted with homogenizer, the hydrolysis of ATP was markedly increased by adding Na plus K . But there was no difference in the Mg-ion system between cell homogenates and whole cell suspensions . ADP, AMP and adenosine as reaction products were found in the reaction mixture which resulted from the hydrolysis of ATP by whole cell suspensions . Our data suggest that Mg-ATPase in the thyroidal isolated cells is an ectoenzyme whose active site(s) are exposed to the external surface of plasma membrane, and that ATP is finally hydrolyzed to adenosine via ADP and AMP by the enzyme(s). J Immunol Methods, 1983 Nov 25, 64(3), 327 - 33 Enrichment of natural killer cells by negative selection: comparison to Percoll gradient separation method; Froelich CJ et al.; A method is described for the preparation of human peripheral blood mononuclear cell (PBMC) suspensions containing highly enriched natural killer (NK) cell cytotoxicity . The technique involved the negative selection of OKM1+ cells by the selective removal of nylon wool nonadherent PBMC which are reactive with the Leu-1 monoclonal antibody . The Leu-1+ cells are removed by subsequent rosette formation with anti-mouse IgG coated bovine erythrocytes . The resultant OKM1+ cell suspension had a greater number of large granular lymphocytes, K562 target binding effector cells, and lytic activity than concomitantly prepared fractions of Percoll gradients. Klin Wochenschr, 1983 Nov 2, 61(21), 1101 - 3 Results with a modified human myeloma stem cell assay; Schmidt-Wolf I et al.; The human tumor stem cell assay (HTSCA) introduced by Hamburger and Salmon {2} was modified in several details . It was found that a short period of treatment with deoxyribonuclease (DNase) of the material aspirated from the patients bone marrow greatly enhances the production of single cell suspensions and thereby may improve the assay . Instead of the dextran sedimentation method, we used the density gradient centrifugation method according to Boyum {1} for the isolation of mononuclear cells from the bone marrow . Another methodical modification introduced by us is the use of the same medium for culturing the cells before plating them and in the agar after plating . Under the conditions reported here the formation of colonies was observed in 8 of 11 samples from individual myeloma patients . The average plating efficiency was 0.024% with a range of 0.009% to 0.039% showing that possibly an improvement was achieved when compared to the results obtained with the original method showing an average plating efficiency of 0.014% {2}. Anticancer Res, 1983 Nov-Dec, 3(6), 401 - 6 Wheat germ agglutinin binding to cells derived from in vivo grown solid tumors; Willmott N et al.; Binding of Wheat Germ Agglutinin (WGA) to cell suspensions derived from in vivo grown solid rat tumors of independent origin and of different metastatic potential has been examined, and results compared with previous work in other systems . The assay used to assess binding was based on the reaction of iodine 125-labelled lectin to tumor cells in suspension and values expressed as per cent of values of a cell line used as internal standard . Inhibition studies showed that WGA binding was principally to sialic acid and/or N-acetyl glucosamine residues . Binding parameters Bmax (maximal binding) and Kd (affinity of binding), derived from Woolf plots and expressed as per cent of internal standard cell line, were found for rat tumors Mc7, Mc40A, Sp24 and Walker 256 . It was observed that cell suspensions derived from the metastatic and most tumorigenic tumor, Walker 256, exhibited a different pattern of lectin binding to the other non-metastatic and less tumorigenic tumors; in particular, Kd values were lower . These results are in accord with work using cell lines selected in vitro and are further evidence for a correlation between the density and/or configuration of cell surface sialic acid residues and metastatic potential. Histopathology, 1983 Nov, 7(6), 841 - 57 Immune marker expression in 53 lymphomas of high-grade malignancy; Pallesen G et al.; Tissue from 53 non-Hodgkin's lymphomas of high-grade malignancy according to the Kiel classification were analysed for cellular immunological markers . In most cases studies were performed in parallel on cell suspensions and cryostat sections . Histologically, the lymphomas were classified as anaplastic centrocytic (four), centroblastic (seven), Burkitt type (three), convoluted-cell type (five) lymphoblastic-unclassified (10), immunoblastic (IBL) (19) and pleomorphic T-cell type (five) . Immunological phenotyping resulted in 60% B lymphomas characterized by monotypic surface membrane Ig (SmIg) and/or cytoplasmic Ig (CIg), and 23% T lymphomas with detectable E receptors; 17% of cases were non-expressive (O-type) . Unusual SmIg-types were noticed in some monoclonal proliferations . Gamma (gamma) and mu chains occurred simultaneously in four cases; delta chain was the only heavy-chain in one case and a heavy-chain was absent in one case . Cases of IBL were of T-cell type in two cases, and two other cases were non-expressive . The cases of B-IBL expressed CIg in 93%, but the B lymphomas other than B-IBL only in 38% . Receptors for Fc-IgG and C3 were expressed by all major immune phenotypes (B, T, O), but were infrequent in lymphoblastic lymphoma unclassified (O-type) . Adoption of immunological techniques to include frozen tissue studies was necessary in order to reach a conclusion regarding the immune phenotype in several cases. Endocrinology, 1983 Nov, 113(5), 1601 - 7 Morphometric analysis of thyrotropes in developing and cycling female rats: studies of intact pituitaries and cell fractions separated by centrifugal elutriation; Childs GV et al.; The development and morphology of immunocytochemically stained thyrotropes were studied in sections of intact pituitaries and dissociated cell fractions separated by centrifugal elutriation . In the initial cell suspension from six elutriation experiments, adult female rat thyrotropes were 4.8 +/- 0.5% (+/- SE) of the cell population . Correlative morphometric studies of Araldite- or glycol methacrylate-embedded pituitaries showed that there were no changes in the percentage of thyrotropes with the stage of the estrous cycle and that the percentage of thyrotropes (5.14 +/- 0.4%) was not significantly different from the percentages in the initial cell suspension . TSH cell area fraction (a) measurements (with a 10,000-microns 2 ocular grid) showed that adult rat thyrotropes covered 171 +/- 5 microns 2 of the grid area and averaged 15 microns in diameter . In neonatal rats, thyrotropes were half the a of those in the adult for the first 9 days of life . Thereafter, they expanded, and the a reached adult levels by 20-21 days of development . TSH cell percentages remained 2-3 times adult levels throughout postnatal development (2-22 days) . This developmental pattern contrasted with that in the male, which showed adult percentages of thyrotropes by 15 days of age . In the elutriation experiments from adult rats, thyrotropes were 2- to 4-fold more concentrated in the fractions eluted at 37.0 ml/min or greater, which contained the largest cells . Fraction 7 (39.5 ml/min) showed a 2-fold enrichment of thyrotropes to 11.6 +/- 1.4%, and fraction 8 showed a 4-fold enrichment to 19.6 +/- 2.7% . A few small TSH cells were found in the fractions 1-3, eluted at 11.8-19.5 ml/min . Electron microscopic studies showed that some of these small TSH cells were poorly granulated and difficult to distinguish from small gonadotropes, whereas the large thyrotropes resembled those described previously in the adult or developing male rat . These studies, thus, combine techniques of immunocytochemistry, morphometrics, and cell separation by elutriation to describe TSH cells in the female rat pituitary . Our findings agree with those reported by Denef et al., who showed that thyrotropes in the adult male rat are among the largest cells in the pituitary . The few small thyrotropes in the female rat may be equivalent to the prolific cells described by Leuschen et al . in the male rat that enrich monolayers from these fractions after 7 days in culture. Cytometry, 1983 Nov, 4(3), 268 - 75 Difference in chromatin sensitivity to heparin of chronic atrophic gastritis, of carcinoma-free and carcinoma-bearing stomach in comparison with normal gastric mucosa and gastric carcinoma as revealed by flow cytometry; Weiss H et al.; DNA distribution patterns from gastric mucosal cells corresponding to four groups defined by histological examination were measured by flow cytometry before and after treatment with heparin, a polyanion . Group I comprised normal gastric mucosal cells; group II, chronic atrophic gastric mucosal cells originating from a carcinoma free stomach; group III, chronic atrophic gastric mucosal cells originating from a carcinoma bearing stomach; and group IV, malignant gastric mucosal cells . The heparin concentrations used were 1.25, 1.5, and 5 U/ml cell suspension . Heparin caused increases in fluorescence intensity and in coefficients of variation, which are interpreted as a reflection of alterations in chromatin structure . For the four groups investigated, the heparin-initiated changes were dependent, in varying degree, on concentration and time . Group I showed a much more extensive sensitivity to heparin than group IV . Group II and III reacted similarly to group I or group IV, depending on the source, i.e., either a carcinoma-free stomach or a carcinoma-bearing stomach . Further extension of this method might yield information concerning the real premalignant potential of a specific case of chronic atrophic gastritis. Cancer Lett, 1983 Nov, 21(1), 95 - 104 Growth in agar and tumor formation in immunologically incompetent mice as criteria for keratinocyte transformation; Cowley G et al.; Established cell lines from 8 human squamous cell carcinomas (SCC) together with normal human keratinocytes, have been investigated for their ability to grow in soft agar and as xenografts when injected as a single cell suspension into immunologically incompetent mice . One of 8 SCC lines formed colonies with efficiencies greater than 1% in soft agar, and only 2 formed progressively growing tumors when injected into animals . It is concluded that these 2 criteria are not reliable markers of malignant transformation in squamous epithelia unless cytological criteria are also applied. J Invest Dermatol, 1983 Nov, 81(5), 397 - 402 Subsets of epidermal Langerhans cells as defined by lectin binding profiles; Schuler G et al.; In this study we characterize the cell surface glycoconjugate moieties of strain 2 guinea pig epidermal Langerhans cells (LC) in single cell suspension by using a battery of 17 fluorescent lectins . All LC displayed binding sites for concanavalin A, succinylated concanavalin A, Lens culinaris agglutinin, Pisum sativum agglutinin, wheat germ agglutinin, succinylated wheat germ agglutinin, Griffonia simplicifolia agglutinin I, Ricinus communis agglutinin I, Phaseolus vulgaris E agglutinin, and Phaseolus vulgaris L agglutinin, but failed to bind Sophora japonica agglutinin (SJA), Dolichos biflorus agglutinin (DBA), and Ulex europaeus agglutinin I (UEA I) . Neuraminidase pretreatment rendered LC reactive for SJA, but not for DBA and UEA I . The binding profiles of certain lectins point to the existence of LC subpopulations in that Griffonia simplicifolia I-B4 isolectin, peanut agglutinin (PNA), Helix pomatia agglutinin, and soybean agglutinin bound to only 80% (range 70-90%) of Ia-positive epidermal cells; binding sites for these lectins on primarily unreactive Ia-positive cells were unmasked when epidermal cells were treated with neuraminidase prior to lectin labeling . Ultrastructural PNA labeling studies revealed that the vast majority of Birbeck granule-containing LC displayed PNA binding sites, whereas indeterminate cells were consistently PNA-negative . Identification of carbohydrate configurations expressed on LC surfaces by lectin binding may provide a clue for the elucidation of the mechanisms of established LC functions and possibly the discovery of as yet unknown properties of this cell type. Gut, 1983 Nov, 24(11), 1034 - 40 Comparative studies of mononuclear phagocyte function in patients with Crohn's disease and colon neoplasms; Beeken WL et al.; Phagocytosis and cellular cytotoxicity by mononuclear phagocytes of blood and intestinal mucosa were studied in patients with Crohn's disease and large bowel neoplasms . Antibody coated sheep erythrocytes were used for phagocytic assays and cellular cytotoxicity in vitro was measured by 24 hour isotope release from 75Selenium methionine-labelled RPMI 4788 human cancer cell cultures in the presence of mononuclear phagocyte-enriched effector populations . The mean percent of mononuclear phagocytes in Ficoll-Hypaque purified mononuclear cell suspensions of blood of healthy controls was 25.9 compared with 44.6 in patients with Crohn's disease, 45.6 in patients with colon neoplasms and 11.6 in intestinal mucosa . Phagocytic indices were similar in all groups, but the phagocytic capacity of mucosal macrophages was twice that of blood monocytes . Mean cytotoxicity of monocytes of patients with Crohn's disease was 12.8% compared with 22.9% for monocytes from normal controls, and 29.4% for patients with colon tumours . Mean cytotoxicity by mucosal macrophages was 18.0% compared with 13.2% by mucosal lymphocyte populations . Exposure of monocytes of Crohn's disease patients to bacterial lipopolysaccharide modestly increased cytotoxicity, but exposure did not alter phagocytosis by monocytes of patients or controls . The results indicate that monocytes of patients with Crohn's disease exhibit subnormal in vitro cytotoxicity . Mucosal macrophages from patients with various diseases show enhanced phagocytosis compared with blood monocytes, and they can mediate cellular cytotoxicity in vitro. J Histochem Cytochem, 1983 Nov, 31(11), 1333 - 5 Method for analysis of cellular DNA content of paraffin-embedded pathological material using flow cytometry; Hedley DW et al.; A method has been developed that allows flow cytometry to be used for measuring the cellular DNA content of paraffin-embedded human tumors . Thick (i.e., 30 micron) sections were cut from tissue blocks using a microtome and dewaxed in xylene . The sections were then rehydrated by sequentially immersing them in 100, 95, 70, and 50% ethanol before finally washing in distilled water . Single cell suspensions were then prepared by incubation in 0.5% pepsin, pH 1.5, at 37 degrees C for 30 min . The cells were counted, washed, and stained with 1 microgram/ml 4',6'-diamidino-2-phenylindole for 30 min, and DNA content was measured using an ICP 22 flow cytometer . There was a good correlation between the DNA histograms produced using this method and those obtained using unfixed tissue from the same tumor stained with ethidium bromide plus mithramycin . This method allows the retrospective study of archival material where the clinical outcome is already known, and it should, therefore, be particularly useful for determining the prognostic significance of abnormal DNA content measured by flow cytometry. J Clin Endocrinol Metab, 1983 Nov, 57(5), 986 - 92 Inhibitory action of bromocriptine and tamoxifen on the growth of human pituitary tumors in soft agar; Arafah BM et al.; Human pituitary tumors were studied in vitro using the clonogenic stem cell assay . Mechanical dispersion was used to prepare single cell suspensions for plating . Colony formation occurred in 21 of 24 tumors plated . Bromocriptine (Brc; 10 nM) added to the medium resulted in a significant decrease in the number of colonies formed in 5 of 10 prolactinomas and in 1 tumor secreting both PRL and GH . However, PRL secretion was decreased in 8 of 9 tumors tested . Brc had no effect on either colony formation or hormone secretion in other tumors secreting GH (n = 2), ACTH (n = 2), or FSH (n = 1) or in nonsecreting tumors (n = 4) . Tamoxifen (Tam; 10(-7) M) inhibited colony formation in 6 of 10 prolactinomas and in 1 tumor secreting GH and PRL . PRL secretion into the medium correlated with the changes in the number of colonies . Tam was not effective in any other tumor tested . In only 1 instance was there a synergistic action between Brc and Tam on inhibition of colony formation . Brc, but not Tam, caused a significant decrease in the size of the colonies formed from cells of PRL-secreting tumors . The least numbers of colonies per plate were found in 3 prolactinomas from patients treated preoperatively with Brc . We conclude that the soft agar clonogenic assay technique is a feasible method to study human pituitary tumors in vitro . Both Brc and Tam inhibited colony formation in this system in a significant proportion of tumors . The potential antiproliferative action of Tam in vivo needs to be studied in view of these results. Cancer Res, 1983 Nov, 43(11), 5451 - 5 New method to quantitate clonogenic tumor cells in the blood circulation of mice; Suzuki N; A bioassay method