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B S Handwerger

Publications and source records attributed to B S Handwerger.

At least 19 recordsLinked to original sources
PubMed1999

Vasculitis in the Palmerston North mouse model of lupus: phenotype and cytokine production profile of infiltrating cells.

OBJECTIVE: To define the phenotype of cells in the perivascular and vascular infiltrates of Palmerston North (PN) mice and the cytokines that those cells produce. METHODS: Immunohistologic analysis, flow cytometric analysis, and reverse transcriptase-polymerase chain reaction (RT-PCR) studies were performed on tissues and cells from female PN mice and age-matched and sex-matched DBA/2 mice. RESULTS: With aging, PN mice developed a female-predominant, lupus-like disease, with a severe systemic mononuclear cell perivasculitis and vasculitis. The perivasculitis involved arteries and veins in kidney, liver, brain, and lung; the vasculitis predominantly involved veins and venules. The perivascular and vascular infiltrates in female PN mice were composed mainly of an unusual cell type that expressed phenotypic markers characteristic of both T cells (Thy1+, CD3+, CD4+, T cell receptor + [TCR+]) and B cells (B220+). In addition, the infiltrates contained a smaller number of conventional CD4+,B220- T cells and macrophages. Very few CD8+ T cells or surface Ig+ B cells were seen. Unlike the Thy1+,B220+ T cells present in MRL/lpr mice, most of which were CD4-,CD8- and TCRalpha/beta+, the majority of the Thy1+,B220+ T cells in the perivascular/vascular infiltrates of PN mice were CD4+ and expressed either TCRalpha/beta or TCRgamma/delta. By immunohistologic staining, the cells in the perivascular and vascular infiltrates in the kidneys of older PN mice were shown to produce interleukin-4 (IL-4), IL-6, and IL-10, but not IL-2, interferon-gamma, transforming growth factor beta, tumor necrosis factor alpha, or IL-1beta. By RT-PCR, the kidneys of older PN mice were found to express high levels of IL-4, IL-6, and IL-10 messenger RNA. CONCLUSION: The vascular and perivascular infiltrates in PN mice are composed predominantly of an unusual subpopulation of T cells that are Thy1+,B220+,CD4+,CD8-, express either TCRalpha/beta or TCRgamma/delta, and produce mainly type 2 cytokines. The exact role of these cells in the immunopathogenesis of lupus-like disease in PN mice remains to be elucidated.

Animals↗
PubMed1999

Further characterization of the autoantibody response of Palmerston North mice.

PN mice spontaneously develop, with age, a lupus-like disease. The present study further evaluated autoantibody production in female PN mice. As early as 1 month of age, all PN mice had detectable IgM antibodies to dsDNA and ssDNA and two-thirds produced IgM anticardiolipin antibodies. By 3 months of age, all PN mice exhibited evidence of isotype switch in their autoantibody response; 88-100% had serum IgG antibodies to ssDNA and dsDNA, respectively. By 6-12 months of age, essentially all female PN mice had IgG antibodies to ssDNA, dsDNA, cardiolipin and other phospholipids (PS, PC, PI, and PG), and IgG and 63% produced IgG anti-mouse erythrocyte antibodies. In addition, 50-100% produced IgA antibodies to dsDNA and ssDNA, and one-third produced IgA anti-IgG antibodies. Antibodies to U1RNP and Sm were present in 81% of 6- to 12-month-old PN mice and 39-94% had IgG or IgM antibodies to mouse thymocytes. Although all four IgG isotypes were represented in the anti-dsDNA response, IgG1 antibodies dominated the IgG anticardiolipin response. The presence of IgA autoantibodies and the predominance of IgG1 in the IgG anticardiolipin response suggest that IL-4 and either IL-5 and/or TGF-beta serve as B cell stimulatory cytokines for autoreactive B cells in PN mice.

Aging↗
PubMed1998

5'-degenerate 3'-dideoxy-terminated competitors of PCR primers increase specificity of amplification.

Amplification of a product in PCR with specific primers may be viewed as an artificial Darwinian-type "selection of the fittest". In other selective systems, such as general evolution, immune system and probably brain cortex, the stringency of selection is not absolute but rather degenerate, with selection of many highly fit units, not limited, however, to only the fittest. In PCR also, annealing of the primers is not absolutely specific. The subsequent amplification frequently leads to amplification of not only the desired product but also to less-specific sequences. Using theoretical analysis of the degenerate mode of selection, we predict theoretically and prove experimentally that 5'-degenerate, 3'-dideoxy-terminated competitors of PCR primers can be used to dramatically improve the specificity of PCR amplification without affecting the quantitation of the final specific product.

Animals↗
PubMed1996

An age-related decrease in rescue from T cell death following costimulation mediated by CD28.

We previously reported that T cell proliferation in response to a primary signal through the T cell receptor (TCR) and a costimulatory signal via the CD28 molecule is impaired in healthy, aged mice. Here we extend these studies to examine factors which may be involved in this defect in T cells from aged mice. To determine if age-related changes in cytokine production might be responsible, splenic T cells from young (2-4 months) and aged (20-26 months) mice were stimulated with immobilized anti-CD3 epsilon and soluble anti-CD28 mAbs in the presence of exogenous IL-2, IL-4, IFN-gamma, IL-1 alpha, or IL-6. No improvement in the proliferative response of T cells from aged mice was found following the addition of any cytokine. In addition, the decreased proliferative response of T cells from aged mice was not caused by the enhanced production of IFN-gamma or other inhibitory factors. Interestingly, despite the age-related reduction in proliferation, no significant difference was found in the percentage of live cells entering the S, G2, or AM phase of the cell cycle in stimulated T cells from young and aged mice. Instead, anti-CD28-mediated costimulation was found to rescue T cells from young mice from anti-CD3epsilon-induced cell death, but did not rescue T cells from aged mice. This failure of T cells from aged mice to respond to costimulatory signals appears to contribute to the decreased proliferation observed from cultures containing these cells, and may be involved in many other age-related alterations in immunological responsiveness.

Aging↗
PubMed1996

Cytokine production by T lymphocytes from young and aged mice.

We previously have shown that T cell proliferation in response to a primary signal through the CD3 epsilon chain and a costimulatory signal via the CD28 molecule is impaired in healthy, aged mice. To determine whether age-related alterations in cytokine production might explain the reduced proliferative responses of T cells from aged mice, we examined the secretion of the major T cell immunoregulatory cytokines, IFN-gamma, IL-4, and IL-2. Splenic T cells from young (2 to 4 mo) and aged (20 to 26 mo) mice were studied. T cells were stimulated with immobilized anti-CD3 epsilon chain mAb and soluble anti-CD28 mAb for 24 h. T cells from aged mice, when compared with young controls, showed increased IFN-gamma production, no difference in IL-4 production, and decreased IL-2 production. Most IFN-gamma was produced by CD8+ T cells, whereas most IL-2 and IL-4 was produced by CD4+ T cells. Both CD4+ and CD8+ T cells from aged mice produced significantly more IFN-gamma than corresponding cells from young mice. This increased production could be accounted for by increased numbers of CD4+CD44high and CD8+CD44high T cells in aged animals. CD4+CD44high and CD8+CD44high T cells from young mice produced comparable amounts of IFN-gamma as corresponding cells from aged mice. In contrast to unseparated splenic T cells, no age-related difference in IL-2 or IL-4 production by purified CD4+ T cells was observed. Similarly, when CD4+ T cells were further separated into CD44low and CD44high subpopulations, no age-related difference in IL-2 production was found. Therefore, we found no consistent evidence that diminished production of the major T cell growth factors, IL-2 and IL-4, is responsible for the age-related decrease in the proliferation of T cell subpopulations that were stimulated in vitro through the CD3 epsilon chain and costimulated via the CD28 molecule. The physiologic relevance of increased IFN-gamma production by T cells from aged mice is unknown.

Aging↗
PubMed1994

Aged T cells are hyporesponsive to costimulation mediated by CD28.

The ability of T cells to proliferate in response to a number of stimuli is impaired in healthy, aged individuals. T cells from young (2 to 4 mo) and aged (20 to 26 mo) mice were stimulated with immobilized anti-CD3 epsilon-chain mAb and soluble anti-CD28 mAb. T cells from young and aged mice proliferated comparably in response to anti-CD3 epsilon mAb alone. However, aged T cells were significantly less responsive to costimulation by anti-CD28 mAb. This decreased response of aged T cells was seen at all dosages tested of anti-CD3 epsilon and anti-CD28 mAbs and in the presence and absence of APC. Similar results were observed when costimulation was provided by B7-transfected L cell fibroblasts. T cells from young and aged mice had comparable expression of CD28 by flow cytometry, both before and after stimulation. The defect in response to CD28 was seen both in CD4+ and CD8+ T cells and in CD44lo (naive) and CD44hi (memory) T cells. The impaired response to costimulation mediated by CD28 on T cells from aged mice may be an important factor in reduced T cell responses associated with aging.

Aging↗
PubMed1993

B-cell and T-cell function in systemic lupus erythematosus.

The process of autoantibody production in systemic lupus erythematosus is characterized by findings of both an antigen-driven response and polyclonal B-cell activation. Autoantibody production does not appear to be critically dependent on the presence of the CD5+ B cell subset. Increasing evidence supports a role for T helper cell type 2 cytokines, such as interleukin-4 and interleukin-6, in promoting and perpetuating B-cell hyperactivity and autoantibody formation.

Animals↗
PubMed1992

Anti-CD4 anti-idiotype antibodies in volunteers immunized with rgp160 of HIV-1 or infected with HIV-1.

We examined the sera of volunteers vaccinated with recombinant gp160 of human immunodeficiency virus type 1 (HIV-1) and control volunteers for the presence of anti-(anti-gp160 idiotype) antibodies which antigenically mimic gp160 and, therefore, bind to CD4 on human cells. Anti-CD4 antibodies were detected in the sera of 3 of 5 rgp160 recipients and 1 of 5 controls by indirect immunofluorescence using CD4-transfected HeLa cells or enzyme-linked immunosorbent assay (ELISA) using recombinant soluble CD4 as the solid phase. The control volunteer who was positive subsequently developed antibodies to HIV-1 by Western blot analysis. The anti-CD4 antibodies detected in the sera of the rgp160 vaccinees and the control volunteer appeared to be anti-idiotypic in nature, reacting with a paratope expressed on goat anti-gp160 antibodies but not on antibodies from normal goat serum. Binding to either transfected CD4+ HeLa cells or blotted anti-gp160 serum could be inhibited by preincubating the anti-CD4 serum with soluble CD4, or preincubating the cells or blotted anti-gp160 serum with recombinant gp160. Anti-CD4 antibodies were initially detectable only after the antibody response to gp160 began to decrease in the vaccinees, and the HIV-1-infected volunteer mounted a detectable anti-HIV-1 antibody response only after a decline in the anti-CD4 antibodies in his serum. These data strongly suggest that anti-CD4 antibodies which are anti-idiotypic to a paratope expressed on anti-gp160 antibodies are generated in response to both vaccination with rgp160 and infection with HIV-1.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS Vaccines↗
PubMed1992

Evidence that the antiproliferative effect of verapamil on afferent and efferent immune responses is independent of calcium channel inhibition.

Calcium channel blockers are capable of inhibiting the afferent and efferent limbs of the immune responses of human peripheral blood mononuclear cells in in vitro systems. This effect is thought to be related to the ability of the calcium channel blocker to limit the transmembrane flux of calcium. We report herein that two optical enantiomers of verapamil, one (S-) which is capable of blocking the slow calcium channel and mitogen-stimulated 45Ca++ uptake into human lymphocytes, while the other (R+) is incapable of either activity, share almost identical capabilities of depressing both the afferent and efferent limbs of immunity. These observations suggest that the inhibitory effects of verapamil on various afferent and efferent immune events are, in part at least, unrelated to the inhibition of transmembrane calcium flux.

Adult↗
PubMed1992

T-cell and B-cell function in lupus.

B-cell hyperactivity is characteristic of lupus and appears to be, in many instances, T-cell driven. Recent work continues to examine the paradox of T-cell activation in vivo and depressed T-cell function in vitro. The role of intrinsic B-cell abnormalities, particularly in CD5+ B cells, is an area of active investigation.

Animals↗
PubMed1991

T-cell and B-cell function in lupus.

Investigation into the nature of the immunologic abnormalities responsible for autoantibody production continues to be an extremely active area of research in lupus. This paper reviews several areas of current research relevant to our understanding of T-cell and B-cell function in lupus.

Animals↗
PubMed1991

Additive inhibition of afferent and efferent immunological responses of human peripheral blood mononuclear cells by verapamil and cyclosporine.

We have studied the effects of verapamil (0-50 microM) on the in vitro immunological function of human peripheral blood mononuclear cells in the presence or absence of cyclosporine (0-600 ng/ml). The proliferative response to phytohemagglutinin, OKT3, and alloantigens, the generation of cytotoxic T lymphocytes following allogeneic stimulation, and mitogen-induced reduction of intracellular ATP were inhibited in a concentration-dependent fashion by verapamil alone and by cyclosporine alone. When the two drugs were added to the same culture, additive inhibition was observed. A verapamil concentration of 5 microM usually reduced by at least 50% the amount of cyclosporine necessary to cause the same level of inhibition seen when no verapamil was present. The additive inhibition of the two drugs was likely not due to additive inhibition of IL-2 responsiveness, since neither drug alone inhibited the response of an IL-2-dependent T cell clone (CTLL-2) to recombinant IL-2 except at the highest concentrations tested, where a mild additive effect was noted. Nor was the additive inhibition related to an additive effect on total IL-2 receptor expression since an additive inhibitory effect on PHA-induced IL-2 receptor expression was only seen with 50 microM verapamil, while additive functional effects on mitogen- and antigen-induced proliferation and alloantigen-induced CTL generation were seen with 5 microM verapamil doses. Verapamil or cyclosporine alone inhibited IL-2 production of PHA- and phorbol ester-stimulated peripheral blood mononuclear cells--however, no additive effect was seen when the two drugs were both added to culture, probably because of the very potent inhibition by cyclosporine alone. Natural killer cell activity of human peripheral blood mononuclear cells against K562 target cells was significantly inhibited by verapamil in a concentration-dependent fashion, while cyclosporine had a more modest concentration-dependent effect. The combination of both drugs demonstrated additive inhibition. Effector function of cytotoxic T lymphocytes was modestly inhibited by either verapamil or cyclosporine alone. A combination of the highest concentrations of verapamil and cyclosporine caused an additive inhibitory effect. In summary, these data demonstrate that verapamil and cyclosporine have concentration-dependent inhibitory activities on both the afferent and efferent limbs of immunity that were additive when verapamil was used in a concentration of at least 5 microM. The additive effects are probably not related to effects on IL-2 circuitry.

Adult↗
PubMed1991

Blood tests in the diagnosis of connective tissue diseases.

Making the diagnosis of connective tissue disease can at times be extremely difficult. Obtaining a complete rheumatological and medical history, and performing a thorough physical examination are absolutely essential. This article has reviewed several of the laboratory parameters which can aid the clinician in the differential diagnosis of connective tissue diseases. Which tests should be ordered in any given individual patient should be determined by the clinical setting. Careful evaluation of the laboratory data, in the context of the patient's history and physical examination, should, in general, allow the clinician to make the proper rheumatological diagnosis.

Connective Tissue Diseases↗
PubMed1990

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)

Adult↗