Biomedical subjects
B S Handwerger
Publications and source records attributed to B S Handwerger.
Acute effects of intravenous cyclosporine on blood pressure, renal hemodynamics, and urine prostaglandin production of healthy humans.
The acute renal failure associated with cyclosporine may result from vasoconstriction of intrarenal arterioles. To evaluate the mechanism of cyclosporine-induced nephrotoxicity, we acutely administered cyclosporine to eight healthy female volunteers with normal blood pressure and renal function. Cyclosporine (4 mg/kg) in 250 ml of 5% dextrose in water (D5W) was administered as a steady intravenous infusion over 6 hr. Glomerular filtration rate and renal plasma flow were measured by serum disappearance of 99m TcDTPA and 131I hippuran, respectively, during the last 3 hr of the infusion. D5W was given to the patients on separate days before the cyclosporine infusion to obtain control data. Systolic and diastolic blood pressure measured every hour during the infusions and renal vascular resistance were slightly higher during cyclosporine administration, but the increases were not statistically significant. Renal plasma flow was not affected by cyclosporine, being 479.6 +/- 24.9 ml/min during the control infusion and 463.3 +/- 12.7 ml/min during the cyclosporine infusion. However, glomerular filtration rate was reduced by cyclosporine in all patients (control, 108.8 +/- 2.5 ml/min, vs. cyclosporine, 91.1 +/- 2.2 ml/min, P less than .01), except one who demonstrated no significant change. Urinary excretion of thromboxane B2 during cyclosporine administration was markedly increased in all patients, being 39.9 +/- 8.2 ng/hr in the control period and 85.8 +/- 22.3 ng/hr during cyclosporine infusion (P less than .05), except for the one patient in whom no decrease in GFR was noted. There was no significant change in the urinary excretion rate for 6-keto-prostaglandin F1a or prostaglandin E during cyclosporine infusion. Serum averaged levels of peripheral renin activity, angiotensin II, and aldosterone did not change during with the cyclosporine administration compared with the control. All patients demonstrated a decrease in 24-h urinary excretion of sodium and potassium on the day of the cyclosporine infusion. Verapamil SR (240 mg daily for 7 days prior to cyclosporine infusion) did not reverse the reduction in glomerular filtration rate induced by cyclosporine; however, a significant reduction in renal vascular resistance and an increase in renal plasma flow (P less than .05) were noted when the volunteers were treated with both verapamil and cyclosporine compared with cyclosporine alone. Intravenous infusion of Cremophor EL, the vehicle to dissolve cyclosporine, demonstrated no significant effects on blood pressure, renal hemodynamics or urinary prostaglandin excretion.(ABSTRACT TRUNCATED AT 400 WORDS)
Additive inhibitory effect of cyclosporine and verapamil may occur through different mechanisms that may be dependent or independent of the slow calcium channel.
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Acute effects of intravenous cyclosporine on renal function in healthy humans.
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Additive effect of cyclosporine and verapamil on the inhibition of activation and function of human peripheral blood mononuclear cells.
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Interleukin 1-mediated activation of interleukin 4 (IL 4)-producing T lymphocytes. Proliferation by IL 4-dependent and IL 4-independent mechanisms.
The role of IL 1 in the activation of IL 4-producing murine T cell clones was investigated by using a calcium ionophore (ionomycin) or a phorbol ester (12-O-tetradecanoylphorbol 13-acetate; TPA) as T cell receptor-independent costimuli. The use of these pharmacologic agents to investigate IL 1-mediated T cell activation revealed two distinct mechanisms of activation. IL 1 in combination with ionomycin (iono/rIL 1) stimulated a proliferative response that was associated with the production of IL 4 as measured by lymphokine bioassay and mRNA studies. Furthermore, inhibition of this proliferative response with an anti-IL 4 monoclonal antibody or cyclosporine indicated that IL 4 functions as an autocrine growth factor. In contrast, IL 1 synergized with TPA (TPA/rIL 1) to induce proliferation in the absence of either IL 4 or IL 2 gene transcription or lymphokine secretion. The IL 4-independence of this activation mechanism was further supported by the failure of both anti-IL 4 antibodies and cyclosporine to inhibit the response. In addition, activation by TPA/rIL 1 caused no detectable alteration in cytoplasmic calcium levels. Both IL 4-dependent and IL 4-independent activation responses were associated with the expression of functional receptors for IL 2 as well as IL 4. Characterization of these activation responses suggests that the synergistic activity of IL 1 during T cell activation is multipotential. The nature of an IL 1-dependent T cell growth response, therefore, may vary depending on the balance of intracellular signals generated concurrently through the T cell receptor complex and other regulatory surface molecules.
Interleukin 2 induces proliferation of normal "resting" human T cells in the absence of other known external stimulation.
Interleukin 2(IL-2) is known to stimulate the progression of activated T cells from G1 through the rest of the cell cycle. We have demonstrated that addition of purified recombinant human IL-2 (rIL-2) to fresh normal human peripheral blood mononuclear cells (PBM), which were IL-2 receptor (Tac) negative by FACS analysis, stimulated marked proliferation of the PBM. IL-2-induced proliferation was also observed with umbilical cord blood mononuclear cells. Monocyte depletion of PBM resulted in a marked reduction of rIL-2-induced proliferative response which could be restored by adding back autologous irradiated monocytes but not by interleukin 1. The T cells preincubated with rIL-2 showed a five to six times enhanced autologous mixed-lymphocyte reaction (AMLR) compared to controls. The rIL-2-induced proliferative response of PBM was inhibited in a concentration-dependent fashion by preincubation of PBM with an anti-HLA-DR framework monoclonal antibody. The proliferating cells were shown by two-color flow cytometric analysis to be primarily Leu-1+ and Leu-4+ T cells (both leu-3+ and Leu-2+ subsets); however, 6 to 19% of responding cells had surface markers for B cells or NK cells. The data demonstrate that rIL-2 can induce proliferation of "resting" human T cells. The phenomenon may be related to a monocyte-dependent AMLR which induces IL-2 receptors and IL-2 responsiveness in a subset of T cells.
A flow cytofluorometric double staining technique for simultaneous determination of human mononuclear cell surface phenotype and cell cycle phase.
A double staining technique for the simultaneous determination by flow cytofluorometry of cell surface phenotype and cell cycle phase is described. Peripheral blood mononuclear cells were stained with fluorescein-conjugated monoclonal antibodies for cell surface phenotype, fixed serially with 2% paraformaldehyde and 71.25% ethanol, and stained with propidium iodide to label cellular DNA. The cells were then analyzed by flow cytofluorometry for both green and red fluorescence. A variety of cells, including T cells and their subsets, B cells, NK cells and monocyte/macrophages, can be identified by this technique with simultaneous determination of cell cycle phase.
Interleukin 2 receptors and responsiveness to recombinant human interleukin 2 in patients with systemic lupus erythematosus.
Defects in interleukin 2 (IL2) responsiveness may contribute to immunologic abnormalities in systemic lupus erythematosus (SLE). We studied the acquisition of IL2 receptors and responsiveness to recombinant human IL2 (rIL2) in the peripheral blood mononuclear cells (PBM) of patients with SLE and matched control subjects. Peak rIL2-induced proliferation was significantly decreased (mean reduction of 58%) in 5 of the 10 patients with SLE. Five of six patients with SLE studied for phytohemagglutinin-induced IL2 receptors had acquisition of IL2 receptors comparable to that of the control subjects. Some patients with SLE have a defect in rIL2-induced proliferation of their "resting" PBM that seems unrelated to a concomitant defect in phytohemagglutinin-induced IL2 receptor acquisition. This finding suggests that the defect in rIL2-induced proliferation may be due to either an abnormality in postreceptor signaling or an impairment in induction of high-affinity IL2 receptors.
Massive acroosteolysis in adult T-cell leukemia/lymphoma.
Adult T-cell leukemia/lymphoma is a relatively uncommon disease, most often found in Japan, the Caribbean, the southeastern United States, and South America. To date there have been few reports of its skeletal manifestations. A case is reported in a 44-year-old man in which a short history of swelling of the hands and feet and painful motion in the fingers was followed by the rapid development of severe acroosteolysis.
Stimulation of resting normal human peripheral blood mononuclear cells by fetal calf sera. Activation to an interleukin-2 responsive state.
Normal adult human peripheral blood mononuclear cells which are negative for interleukin-2 (IL-2) receptors as assessed by flow cytofluorometry, acquire IL-2 receptors and IL-2 responsiveness after culture in media supplemented with fetal calf sera. Thus, in the absence of any known external stimuli, fetal calf sera used to supplement culture media can induce the transformation of resting (G0) peripheral blood mononuclear cells to an activated (G1) state. The activated (G1) cells are able to progress through the rest of the cell cycle (S, G2, M) in the presence of IL-2. As a result, studies of human peripheral blood mononuclear cells in fetal calf serum-supplemented culture media should be interpreted with appropriate caution.
T-cell chronic lymphocytic leukemia with a helper/inducer membrane phenotype: a distinct clinicopathologic subtype with a poor prognosis.
T-cell chronic lymphocytic leukemia (T-CLL) accounts for about 2% of the various types of CLL and can be subtyped into helper/inducer (h/i) and cytotoxic/suppressor (c/s) cell membrane phenotypes. Seven patients with CLL were shown to have T-CLL with a h/i cell membrane phenotype; four with monoclonal antibody reagents and three by demonstration of the E-rosette receptor and focal acid alpha naphthyl acetate esterase activity. The clinical courses, treatment responses, and laboratory findings of these seven patients were reviewed to determine the prognosis and unique clinicopathologic features of this subtype. Two patients presented with skin rashes, and five were diagnosed during evaluation for other medical problems. Initially, four patients had splenomegaly and two had lymphadenopathy, but none of the patients had hepatomegaly. Morphologic examination revealed uniform, small lymphocytes in three patients, and the lymphocytes had nuclear indentations in four patients. Sera from the three patients tested were negative for antibody to the human T-cell leukemia/lymphoma virus I. Peripheral blood mononuclear cells from one patient showed normal interleukin-2 production and lacked antibody-dependent cell-mediated cellular cytotoxicity and natural killer activity. Cytogenetic analysis was done on one patient, revealing an abnormal clone with several chromosomal abnormalities, including an X;14 translocation with a break point at 14q11. All patients required chemotherapy, and all died a median of 21 months from the time of diagnosis. The findings in these patients, in addition to those in 31 patients described in the literature, indicate that h/i T-CLL is associated with a poor prognosis and has distinct clinical and pathologic features that separate it from c/s T-CLL, adult T-cell leukemia/lymphoma, the cutaneous T-cell lymphomas, and B-CLL.
Establishment of monoclonal antibodies which possess the same characteristics as the naturally occurring thymocytotoxic autoantibodies (NTA).
Autoantibody-secreting hybrid cell lines were obtained by fusion of spleen cells from unimmunized (NZB X NZW) F1 mice with the HAT-sensitive mouse myeloma cell line SP2/0-Ag14. Eight hybridoma cell lines producing autoantibodies to mouse thymocytes were cloned and the resultant antibodies were partially characterized. All eight monoclonal antibodies lysed mouse thymocytes in the presence of rabbit complement. The anti-thymocyte cytotoxic antibody activities were absorbed with thymocytes, lymph node cells, unfractionated spleen cells, and splenic T cells; but not with bone marrow cells, splenic B cells, or homogenates of mouse kidney, liver, or striated muscle cells. In addition, the cytotoxic activities of culture supernatants from seven of the eight hybrid clones were absorbed with mouse brain tissue homogenates. Isotyping of the monoclonal antibodies revealed that five were IgM and three were IgG2a. Mouse thymocytes sensitized with each of the eight monoclonal antibodies in vitro became highly susceptible to phagocytosis by syngeneic macrophages. The monoclonal antithymocyte antibodies, thus, appear to be similar to the naturally occurring, (NZB X NZW) F1 thymocytotoxic autoantibodies (NTA) described by Shirai et al.
Stimulation of arachidonic acid release and eicosanoid biosynthesis in an interleukin 2-dependent T cell line.
Previous studies have provided pharmacologic evidence that T lymphocyte function may be regulated in part by the intracellular production of various arachidonic acid (AA) metabolites in response to cellular stimulation. However, the specific AA metabolic capabilities of homogeneous T cell populations have not been clearly defined. In the present studies, we have employed an accessory cell-free T cell line, HT-2, as a model system for the examination of stimulus-induced eicosanoid biosynthesis in T lymphocytes. HT-2 cells were biosynthetically labeled with [3H]-AA and challenged briefly with various agents that stimulate the hydrolytic release of AA from cellular phospholipids. The bee venom peptide melittin stimulated a profound AA release response in the cells and the concomitant synthesis of both cyclooxygenase (PGF2 alpha, PGE2 and PGD2) and lipoxygenase (5-,12-,15-HETE and possibly 5-,12-diHETE) metabolites of AA. The formation of PGs was blocked by 5 microM indomethacin, demonstrating that this cell line contains cyclooxygenase activity functionally similar to that described in macrophages and other cell types. The high activity of melittin in this system was shown to result largely from a synergy between the peptide itself and a persistent bee venom phospholipase A2 contaminant. However, experiments with melittin freed of detectable phospholipase A2 activity by heating, and with synthetic homopolymers of (L)-lysine and (L)-arginine demonstrated that HT-2 cells contain sufficient endogenous, stimulus-responsive phospholipase A2 to provide both the cyclooxygenase and lipoxygenase pathways of AA metabolism ith substrate. In contrast, Ca++ ionophores, which are known to stimulate AA release and metabolism in certain cell types, stimulated only AA release but no detectable eicosanoid biosynthesis in HT-2 cells. Experiments with exogenous bacterial phospholipase C suggested that this cell line can also generate free AA for eicosanoid biosynthesis from membrane-derived 1,2-diacylglycerol. These results indicate that multiple intracellular pathways of AA metabolism are present HT-2 cells, and that the stimulus-induced release of AA and the production of eicosanoid second messengers may result from activation of either phospholipase A2 or phospholipase C.
Lymphocytic hypophysitis with isolated corticotropin deficiency.
In a 32-year-old woman, acquired, isolated corticotropin deficiency resulted from postpartum lymphocytic hypophysitis. The literature suggests that lymphocytic hypophysitis may cause acquired deficiencies of anterior, and possibly posterior, pituitary hormones. Immunologic evaluation of our patient failed to uncover anticorticotroph antibodies. Prompt recognition of this potentially fatal condition is important because of the availability of effective treatment.
Regulation of growth of an interleukin 2 (IL-2)-dependent murine T-cell clone (HT-2) in a defined serum-free medium.
In this study, we demonstrate that an IL-2-dependent T-cell clone (HT-2) can be grown in a serum-free medium (HB101) with defined additives at rates comparable to those which can be obtained in serum-containing medium. Further, we show that cells cultured in the serum-free medium in the absence of IL-2 arrest growth in the G1 portion of the cell cycle, and that these arrested cells can be stimulated to reenter the cell cycle upon the addition of IL-2 to the culture medium. Growth of these cells in the absence of serum requires the presence of IL-2 as well as other hormones and growth factors and 2-mercaptoethanol. HT-2 cells have been grown continuously in the serum-free medium for periods of up to 1 month.
The role of IL 1 in the antigen-specific activation of murine class II-restricted T lymphocyte clones.
The role of IL 1 in the antigen-specific activation of class II-restricted T lymphocytes was examined by using a model system consisting of cloned WEHI 5 B lymphoma accessory cells and class II-restricted, soluble antigen- or alloantigen-reactive T cell clones. The addition of exogenous recombinant IL 1 to the T cell cultures resulted in a significant enhancement of the antigen-specific T cell proliferation response, but at best, only small increases in IL 2 release. Goat IgG anti-IL 1 antibodies were added to the T cell cultures to assess their effect on T cell activation. The IL 1 enhancement of the T cell proliferation response was inhibited by the anti-IL 1 antibodies in a dose-dependent manner. In contrast, only modest levels (10 to 25%) of proliferation inhibition were observed in T cell cultures containing either WEHI 5 or splenocyte accessory cells but no exogenous IL 1. When the anti-IL 1 antibodies were added to primary mixed lymphocyte cultures stimulated by WEHI 5 cells in the absence of exogenous IL 1, no significant inhibition of proliferation was observed. A small but statistically significant proliferation inhibition was observed when anti-IL 1 antibodies were added to mixed lymphocyte reaction cultures stimulated by splenocytes. Two-color cytofluorometric analysis of the effects of IL 1 on antigen-activated T cell clones demonstrated that under suboptimal stimulation conditions, IL 1 stimulated a small but significant increase in the number of T cells bearing IL 2 receptors. In the presence of optimal numbers of WEHI 5 accessory cells, IL 1 enhanced T cell proliferation in the absence of a detectable increase in the number of T cells bearing IL 2 receptors, the number of IL 2 receptors per T cell, or the levels of IL 2 released. Finally, exogenous IL 1 can be added as late as 18 to 24 hr after culture initiation without significantly reducing its ability to enhance the T cell proliferation response. These data indicate that IL 1 has pleiotropic effects on murine T lymphocytes and can function to enhance T cell activation at multiple points during the activation sequence.
Alterations in immunological reactivity in encephalomyocarditis virus-induced murine diabetes. I. Defective primary IgM plaque forming cell responses to sheep erythrocytes: correction by islet cell transplantation.
Increasing data suggest a possible viral aetiology of juvenile onset, insulin-dependent diabetes mellitus. The M variant of the encephalomyocarditis (EMC) virus infects murine pancreatic beta cells and causes a diabetes like syndrome in susceptible strains of mice. Abnormalities in immunological function have been documented in patients with diabetes mellitus and in spontaneous, streptozotocin-induced and alloxan-induced diabetes in animals. The present study documents a significant impairment of the ability of mice with EMC virus (M variant)-induced diabetes to generate a direct, IgM PFC response after in vivo immunization with sheep erythrocytes. This abnormality appears to be a direct consequence of the diabetic state and not EMC virus infection, per se, since mice infected with EMC virus that do not become diabetic have normal direct PFC responses and islet cell transplantation, which cures the diabetes, corrects the defect in PFC responsiveness.