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The life span of rabbit lymphocytes carrying radiation-induced chromosome aberrations has been studied by following the decline in aberration frequency as a function of the time after irradiation. Female rabbits were given a whole body X-ray dose of 300 rad. The day before exposure and at 2 hours, 14, 28, 42, 56, 84, 140, 250 and 500 days thereafter, blood samples were taken from a marginal ear vein of each animal. A plot of log abnormalities against time suggests an exponential decline for dicentrics and fragments up to 140 days, the half time for dicentrics and fragments being 70 and 46 days respectively. The results of the present investigation thus demonstrate that because of their shorter life span, in vivo observations on aberrations in rabbit lymphocytes are not suitable for extrapolation of information on chronic exposure to man.

The uptake and binding of 59Fe, 67Ga and 239Pu complexed with citrate of transferrin (Tf) and of 125I-labelled Fe-Tf by human lymphoblasts (WI-L2 cells) have been studied. Uptake kinetics of 59Fe-Tf and [125I]-Tf point to internalization by receptor mediated endocytosis. 67Ga binding and uptake is always less. This may be explained by a lower affinity of Ga-complexes for the cell surface. Factors which influence Fe uptake have a similar effect on Ga. 239Pu uptake and binding, however, are different, especially in that Tf does not stimulate 239Pu uptake and may actually decrease it.

After cessation of cisplatin (cis-dichlorodiammineplatinum) chemotherapy, selective recovery of certain cell lineages occurs during bone marrow hemopoiesis. To further investigate the process of selective hemopoiesis, we combined the use of buoyant density gradient separation, morphology, and lymphocyte function assays to characterize changes in the hemopoiesis of immature and mature marrow cells after exposure to cisplatin. A single, cytotoxic dose of cisplatin was administered to B6D2F1 male mice, and marrow cell suspensions were taken from these mice 3 and 7 days later to characterize hemopoietic recovery. Morphology and buoyant density separation of marrow cells revealed that the most significant changes in cellular composition occurred at Day 3. At this time, there was an increase in immature white blood cells (WBCs) and immature polymorphoneutrophils (PMNs) with a concomitant reduction in immature red blood cells (RBCs). By Day 7, the normal proportion of immature RBCs, immature WBCs, and PMNs was restored; however, the buoyant distribution patterns for PMNs indicated that a greater proportion of immature PMNs was still present relative to marrow suspensions from normal mice. Fewer lymphocytes were also observed in marrows from the Day 7 group when compared with controls. Lymphocyte function tests indicated reduced mitogen responsiveness of lymphocytes from both Day 3 and Day 7; however, more immature lymphocytes were present after 7 days than were seen with either normal or Day 3 marrow suspensions. Overall, the results indicated that hemopoiesis proceeded through a specific hierarchy which began with the restoration of the erythrocyte line followed by the leukocyte cell lines. Lymphocyte recovery lagged behind the restoration of all the cell lineages examined.

Large numbers of plasmacytes and lymphocytic cells develop at the tip of miniature pipettes containing phytohemagglutinin (PHA) implanted into the brain of adult Lewis rats. The accumulation of lymphoid elements is present in tissue exposed to PHA for 1 week, and it persists in animals which were allowed to survive up to 10 weeks. It did not occur around control or non-active implants. Lymphoid cells usually serve as a morphologic index of immune mediated phenomena, but no evidence was seen in the present study to indicate that they produce damage to axons, dendrites or glial cells of the central nervous system despite direct contact with them. Plasma cells in the brain appear to develop from "dark" cells resembling lymphocytes that migrate into the central nervous system from reactive lymphoid tissue near the tip o.f the implant. Nerve, glial and subependymal cells do not respond with mitogenic activity to PHA.

The two-dimensional gel electrophoresis (2-DE) method developed by O'Farrell was used to analyze the differences of major proteins between lymphoblasts from children with acute lymphocytic leukemia (ALL) at diagnosis (lymphoblasts, n = 6), normal lymphocytes (n = 6) and lymphocytes from children with ALL in complete remission (lymphocytes in CR, n = 12). Among all the spots, those which were deeply stained and large were termed 'major spots'. Their number was 118. Two spots (No. B1 and B2) were characteristic of lymphoblasts, three spots (No. N1-N3) were characteristic of normal lymphocytes. In lymphocytes in CR, the latter spots were not always detected, and furthermore, the former spots were detected in several gels. These findings may relate to the insufficient recovery of functions of lymphocytes in CR. Several spots (No. 6, 55 and 57) in lymphoblasts were remarkably larger than those in normal lymphocytes. Spot No. 67, an actin spot, in lymphoblasts was smaller than that in normal lymphocytes. Spots No. 6, 55 and 57 in lymphocytes in CR were relatively small in size.

A gene in the heterozygous state appears responsible for a 2-fold increase in pyrophosphate content of both fibroblasts and lymphoblasts cultured from patients who have dominantly inherited chondrocalcinosis. Cells from unaffected family members of this large kindred showed a pyrophosphate content in the same range as was found in unaffected, unrelated controls. Similar cells from individuals homozygous for the gene would be useful in delineating the precise biochemical abnormality responsible for the increased pyrophosphate content.

The effect of cyclosporin on an immunological autoreactive experimental model was analyzed. The experimental system consisted of X-irradiated A mice injected with syngeneic concanavalin A-induced lymphoblasts and footpad-challenged 7 days later with syngeneic lipopolysaccharide-induced lymphoblasts. 24-72 h after challenge, the footpads of these mice responded with significant swelling, accumulation of 125I-UdR or massive cellular infiltration revealed by histological examination. Since the immunological activity was transferred by Lyt-1+ T cells from the sensitized donors to naive recipients, we designated it 'syngeneic delayed-type hypersensitivity' (syn-DTH). This DTH was induced and elicited mostly by antigens of the syngeneic lymphoblasts and not by contaminants attached to them, indicating the immunological autoreactive nature of this system. Multiple doses of 60 mg/kg cyclosporin, given daily in the time interval between immunization and challenge, or on the last four days before challenge, inhibited the syn-DTH. Multiple injections of cyclosporin Before or close to the induction phase of the syn-DTH was ineffective, whereas single or multiple injections of cyclosporin close to the effector phase (the challenge time) markedly reduced the syn-DTH. Even a single injection of cyclosporin 24 h after the challenge efficiently reduced the 48-h syn-DTH. Adoptive transfer experiments revealed that T cells from X-irradiated mice immunized with concanavalin A-induced lymphoblasts and injected with cyclosporin, failed to efficiently transfer the syn-DTH response to naive recipients. Similarly, the syn-DTH response of naive X-irradiated recipient mice injected with cyclosporin, failed to be reconstituted with primed T cells derived from X-irradiated mice immunized with concanavalin A-induced lymphoblasts. Since the nonspecific footpad swelling response of X-irradiated mice challenged with lymphoblasts alone is resistant to the standard protocol of the cyclosporin treatment, we suggest that cyclosporin inhibits the ability of T cells to produce or release lymphokines at the effector phase of DTH, while phagocytic cells involved in the DTH response are not affected by it. The practical and the theoretical implications of this research are discussed.

The development and the regression of the cell populations in the thymus of the newt Pleurodeles waltlii Michah., from hatching (14 days) until the adult aged 600 days, were studied by means of histological and autoradiographic methods, and by using the Samba 200 cell images analyser. Cell counts show a quasi-exponential growth up to metamorphosis; then, after a short plateau, they begin to decrease slowly. The labelled-mitoses curves demonstrate the progressive lengthening of the generation time. Growth fraction, labelling index, and mitotic index increase up to stage 50, then decrease progressively. Careful microscopic observation allows to distinguish several cell populations; they can be taken into account by the cell images analyser, which is able to discriminate for each of them the cycling cells (growth fraction) and non-cycling (Go) cells. This leads us to propose a comprehensive view of the developmental history of the thymus, from stage 42 to adult, including the migration of the Go stem cells into the thymic bud, the start of their proliferation and differentiation into lymphoblasts according to a precise schedule, and including also the proportion of functional T-lymphocytes leaving the thymus during each period. Two hypotheses concerning the relationships between lymphoid cell population proliferation and differentiation are discussed; one of them fits perfectly all the experimental data, and gives us a complete view of the development and of the regression of this complex organ.

Polybrominated biphenyls (PBB) have been shown to affect the immune system of exposed Michigan farm workers and their families. The purpose of this study was to evaluate the effects of PBB on the function and on the synthesis of immunoglobulins by peripheral blood lymphocytes. Concentrations of PBB as low as 0.001 microgram/10(5) cells decreased lymphocyte response to pokeweed mitogen; higher concentrations of PBB stimulated the in vitro synthesis and release of immunoglobulins. PBB had no effect on the quantity of E-rosette-forming cells, the total T or B cells, or the ratio of helper to suppressor T-cell subpopulations. Enhanced release of IgG was identified in lymphocyte cultures obtained from blood specimens of PBB-exposed Michigan farmers. The data from this study suggest that PBB exerted an adverse effect on cell function, but produced a nonspecific activation of B lymphocytes.

The Syrian hamster has a diploid chromosome complement similar to humans in both number (2N = 44) and morphology. For comparative mutagenic studies with humans, a repeatable lymphocyte chromosome technique involving laboratory mammals is desirable. The reported hamster lymphocyte cytogenetic technique appears technically uncomplicated and repeatable while providing a sufficient number of metaphase cells for quantitative analysis. In order to determine the effects of storing whole-blood (in culture media) for varying time periods at 8 degrees C prior to adding a mitogen, the mitotic index was calculated following a 48-h culture period. Results indicated that storage up to six days can still result in a mitotic index adequate for cytogenetic analyses.

Tissue cultures were established from biopsy specimens of adenocarcinoma of the prostate (ACP) and benign prostatic hyperplasia (BPH). Generally, peripheral blood lymphocytes from BPH and ACP patients were cytotoxic to both ACP and BPH cells, but not normal fibroblasts nor cells cultured from other types of malignant tissue. Peripheral blood lymphocytes from normal control patients or from patients with other types of cancer were not cytotoxic to ACP- or BPH-derived cells. These findings are consistent with a cross reactive autoimmune response in ACP and BPH patients, directed against a common antigen(s) present on both ACP and BPH cells.

Cultured human lymphoblastoid cells exposed for short times to retinol and retinoic acid, undergo a time- and dose-dependent decrease in viability, accompanied by cell swelling. The presence of taurine (5-20 mM) and zinc (50-100 microM) protected cells from retinol-induced injury. Taurine 20 mM and zinc 100 microM added simultaneously abolished cell swelling and increased cell viability from 7 to 55%. Tocopherol (200 microM) was also effective in protecting these cells from retinol. The three compounds together afforded complete protection. The effects of retinol and of taurine, zinc or tocopherol seem to be unrelated to lipid peroxidation. A membrane stabilizer action is proposed as the mechanism underlying the protective effect of taurine and zinc or of tocopherol.

Using in vitro immunization with a human plasma protein (apolipoprotein-A1) as antigen, we have shown that it is possible to prepare more monoclonal antibodies using a ten-fold lower concentration of antigen compared to in vivo immunization procedures (Weech et al., 1985). In addition, we can increase the number of Ig-producing hybridomas after in vitro immunization by a simple one-step separation of the lymphoblasts on a Percoll gradient before the fusion procedure. In order to apply this procedure to in vivo immunization techniques, it is necessary to expand the B-blast/plasma cell population by culturing the spleen cells for 4-6 days before fusion. Only antibodies of the IgM class were produced with the in vitro technique. However, by combining in vivo priming with in vitro immunization, it is possible to produce specific antibodies to both IgG and IgM classes.

The effects of 2 microtubular-disruptive drugs, colchicine and vinblastine, on the phytohaemagglutinin (PHA)-induced blast transformation and mitogenic stimulation of human lymphocytes were studied. Both drugs markedly inhibited cell growth and DNA synthesis and lowered the mitotic index. No microtubules were seen with the electron microscope in cells treated with PHA plus colchicine or vinblastine. Moreover, the PHA-induced development of all organelles was partially inhibited by these drugs, especially that of the Golgi complex. As compared to cells treated with PHA alone, the dictyosomes were fewer, not so clearly localized in one area of the cytoplasm, and contained a decreased number of cisternae and an increased number of vacuoles. These results indicate that cytoplasmic microtubules play an important role in the PHA-induced blast transformation and mitogenic stimulation of lymphocytes. It is suggested that the microtubules function in the structural organization of the cell and particularly the Golgi complex. In the drug-induced absence of microtubules this and other organelle systems do not respond as usual to PHA stimulation, which could largely explain the decreased cell growth. This in turn suggests that lowered mitotic activity is a result of inhibition of cell growth, as a critical amount of G1-associated cell growth is believed to be required for the initiation of DNA synthesis and thus mitosis.

Sera obtained before transplantation from 52 consecutive renal allograft recipients were tested for antibody-dependent cell-mediated cytotoxicity (ADCC) and for complement-dependent cytotoxic antibodies (CDC). A D locus antigen-defined lymphoblastoid cell panel (B lymphoblastoid cell panel) was used as targets for the ADCC, and a peripheral blood lymphocyte (PBL) panel from 40 donors was used as targets for the CDC. Of the 343 ADCC assays, 118 of 168 performed with pretransplant sera from 24 recipients with early graft loss were positive, whereas only 81 of 175 performed with pretransplant sera from 25 recipients with a successful graft outcome were positive (P less than 0.001). A significantly greater degree of presensitization to the B lymphoblastoid cell panel was found in the group that lost their grafts as compared to the group with successful grafts (69% versus 49%, P less than 0.001). Sera from all six recipients with hyperacute rejection were positive in the ADCC before and after absorption with pooled platelets. In contrast, pretransplant CDC results were not predictive of ultimate graft outcome. Utilizing any level of cytotoxicity against the PBL panel as an index of adverse presensitization, no significant correlation between pretransplant CDC results and graft outcome was observed. These results suggest a prognostic role for ADCC using a B lymphoblastoid cell panel as targets to screen and identify high-risk potential graft recipients.

The interaction of histocompatibility (HL-A) antibodies and complement with synchronized human lymphoid cells in continuous culture has been investigated. The sensitivity of cultured lymphoid cells to HL-A antibody-mediated lysis in the cytotoxic test, the extent of activation of the complement system, the degree to which labeled complement components are bound, and the ability of these cells to absorb HL-A alloantibodies do not vary significantly during the cell growth cycle. The constancy of histocompatibility antigen expression throughout the growth cycle of cultured cells suggests that these cell surface markers are an essential part of membrane cytoarchitecture and could well play a critical role in determining the normal function of the cell membrane.

These experiments describe the preparation of pure marrow-derived lymphocyte suspensions from the thoracic duct of thymectomized, irradiated rats reconstituted with bone marrow cells. The majority of marrow-derived cells were small lymphocytes morphologically indistinguishable from small lymphocytes in thoracic duct lymph of normal donors. Marrow-derived small lymphocytes (B lymphocytes) were a predominantly long-lived population; the frequency of short-lived B lymphocytes in the thoracic duct was not significantly higher than the frequency of short-lived small lymphocytes in normal lymph. B lymphocytes transferred to normal recipients recirculated from blood to lymph. The first appearance of intravenously injected B lymphocytes in the thoracic duct was delayed relative to lymphocytes from normal donors and there was no clear cut modal recirculation time. Nevertheless their recirculation over a 48 hr period after transfusion was of the same order of magnitude as that of lymphocytes from normal donors.