Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate whether the T cell defective capacity to proliferate observed in systemic lupus erythematosus (SLE) T cells is a possible consequence of an intrinsic T cell disorder, the integrity of the accessory activation pathway mediated through CD26 antigen in SLE T cells was studied. Hyporesponsiveness of peripheral blood mononuclear cells (PBMC) from SLE to PHA and CD26 Mab was observed and no differences were found when the responsiveness of highly purified T cells to IL-2, IL-2 plus CD26 Mab, phorbol 12-myristate 13-acetate (PMA), or when PMA plus CD26 Mab was analyzed. Findings suggest that signals induced by triggering CD26 are not intrinsically altered in SLE T cells. However, some alteration of the regulatory involvement of monocytes or B cell over T cell function may be involved.
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PMID:Responsiveness of T lymphocytes from systemic lupus erythematosus to signals provided through CD26 antigen. 791 57

Cell surface carbohydrate antigens have been implicated in cell differentiation and maturation and may play a role in immunoregulation. The expression of carbohydrates in peripheral blood lymphocytes (PBL) was studied by double immunofluorescence flow cytometry, using MoAbs CT1 and CT2 but only a small proportion of cells bound these MoAbs. MoAbs CT1, CT2 and the lectin vicia villosa (VV) which share specificity for Gal NAc were then used to examine lymphocytes from patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Behcet's disease (BD) and IgA nephropathy. A significant increase in MoAbs CT1 CT2 and VV binding CD4 or CD8 cells was found only with lymphocytes from patients with SLE. However, MoAbs CT or VV binding lymphocytes from healthy subjects were significantly up-regulated by activation with a mitogen (PHA), cross-linked anti-CD3 MoAb or a common antigen (65kDa heat shock protein), suggesting that an increased proportion of T cells expressing these carbohydrates results from any of the three types of lymphocyte activating agents. Inhibition studies were then carried out to determine the relationship between the MoAbs CT1 and CT2, VV and GalNAc. Indeed, VV binding to T cells was significantly inhibited by either MoAbs CT1 or CT2, or GalNAc but not GlucNAc, suggesting that VV shares a common binding site with MoAb CT and that GalNAc may constitute one of the sugar receptors. Investigations of lymphocytes from adult peripheral blood in health and disease suggest that carbohydrate antigens may play a role in activation and immunoregulation.
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PMID:The expression of carbohydrate antigens in activated T cells and in autoimmune diseases. 799 53

In the present study we have examined the potential contribution of IL-2/IL-2R interactions in CD3-mediated responses by T lymphocytes from patients with systemic lupus erythematosus (SLE). T-cells from SLE patients showed normal IL-2 production when activated with OKT3 MAb and submitogenic concentrations of PMA, in cultures in which uptake of endogenous IL-2 was prevented by pretreatment with anti-Tac MAb. In contrast, PHA-induced IL-2 production was lower in patients under the same conditions. Under these stimulatory conditions the proportions of T-cells expressing IL-2R CD25 molecules was comparable in patients and controls. There was earlier and higher binding of exogenously added IL-2 in T lymphocytes from patients activated via the CD3 pathway. Furthermore, these cells responded to IL-2 with stronger proliferative responses than cells from control subjects. These findings may partly explain the increased proliferative responses of SLE T-cells when stimulated via the CD3 pathway.
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PMID:T lymphocytes from patients with systemic lupus erythematosus show increased response to interleukin-2 after costimulation with OKT3 monoclonal antibody and phorbol esters. 826 71

13-cis-Retinoic acid (13-CRA), a water-soluble vitamin A analog and 5'-lipoxygenase inhibitor, was tested in vitro for effects on excess oxidative metabolism and DNA damage in mitogen-stimulated lymphocytes from patients with systemic lupus erythematosus (SLE), because other 5'-lipoxygenase enzyme inhibitors were shown to lower the excess oxidative metabolism in SLE cells. Excess chemiluminescence (CL) was abolished within minutes after the addition of 1 x 10(-6) M 13-CRA in five of five CL-positive mitogen-stimulated SLE lymphocytes, and was lowered in five of eight samples after 48 to 72 h culture. Similarly, low concentrations of 13-CRA for 48-72 h largely prevented the S1 nuclease-sensitive DNA changes/DNA damage observed in CL-positive lupus lymphocytes in vitro. However, 13-CRA did not affect DNA damage in four of four CL-negative lymphocyte samples. 13-CRA, like other retinoic acid compounds, was known to stimulate B-cell activities in vivo and in vitro but effects on dividing lupus T cells had not been studied. 13-CRA further inhibited the diminished PHA-stimulated lupus T-cell growth in tissue culture at a concentration of 9 x 10(-6) M in three of five lupus lymphocyte samples. 13-CRA has positive and negative effects on multiple aspects of the immune system and it is not clear whether 13-CRA will have positive or adverse clinical effects on SLE patients. Close attention to vitamin A and vitamin "supplements" in patients with SLE may answer this question.
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PMID:13-cis-retinoic acid affects oxidation and DNA damage in oxidative-positive SLE lymphocytes but may not be useful for therapy. 843 47

Thymulin is a nonapeptide hormone isolated from the thymus gland. It has immunomodulatory effects which have not yet been well defined. Its major actions have been shown to be on T-cells and their immature precursors. In this study, thymulin was tested in vitro for its effect on the release of IL-1 alpha, IL-2, IL-6 and TNF alpha from peripheral blood mononuclear cells (PBMC) obtained from normal volunteers and patients with active systemic lupus erythematosus (SLE). In our experiments, PBMC (stimulated with LPS or PHA) were cultured for 24 h in the presence of 1,100 or 1,000 ng/ml of thymulin. Supernatants were subsequently assayed for cytokine activities using commercially available ELISA (IL-2, IL-6 and TNF alpha) and RIA (IL-1 alpha) kits. Thymulin (1 ng/ml) resulted in a significant (p < 0.01) increase in IL-1 alpha in the volunteers and a significant (p < 0.05) inhibition of this cytokine at all dose levels tested in SLE patients, whose basal levels of IL-1 alpha were significantly (p < 0.05) higher. Thymulin significantly (p < 0.05) inhibited IL-2 only in SLE patients at 1,000 ng/ml. At all dose levels tested, thymulin significantly (p < 0.01) inhibited IL-6 in volunteers, and, only at 1,000 ng/ml, it significantly (p < 0.05) inhibited it in patients with SLE. At the 1,000 ng/ml dose level, TNF alpha was significantly (p < 0.05) inhibited in both volunteers and SLE patients, whose basal levels of this cytokine were significantly (p < 0.05) higher.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Thymulin modulates cytokine release by peripheral blood mononuclear cells: a comparison between healthy volunteers and patients with systemic lupus erythematosus. 850 50

Accumulated evidence suggests that prolactin (PRL) is an important immunoregulator and might have a role in the pathogenesis of systemic lupus erythematosus (SLE). Moreover, a PRL-like molecule is secreted by normal human lymphocytes and acts as an autocrine growth factor for lymphoproliferation. The objective of this study was to explore the PRL-like peptide production by peripheral blood mononuclear cells (PBMC) from patients with SLE. We investigated the PRL secretion by PBMC from six female SLE patients and nine normal subjects (5 women and 4 men). Ficoll-Hypaque isolated PBMC (1 x 10(6) cells/ml) were cultured with and without maximal stimulatory doses of PHA (1 mg/ml) or PWM (1/200). At 72 h of culture supernatants were harvested and used to determine PRL immunoreactivity by a radioimmunoassay (NIDDK-reagents). Cell extracts and concentrated supernatants were prepared to determine PRL by Western blot analysis (NIDDK-reagents). SLE non-stimulated PBMC secreted significantly higher levels of PRL than normal non-stimulated PBMC (8.09 +/- 4.15 ng/ml vs. 3.48 +/- 2.36 ng/ml, P = 0.02 by Mann-Whitney test). High levels of PRL were secreted by SLE-PHA stimulated PBMC (6.88 +/- 4.53 ng/ml) and SLE-PWM stimulated PBMC (16.57 +/- 16.39 ng/ml) compared with normal-PHA stimulated PBMC (5.83 +/- 5.27 ng/ml) and normal-PWM stimulated PBMC (8.54 +/- 5.49 ng/ml), respectively, but the differences were not significant. The maximal production of PRL was found in PWM-stimulated lymphocytes in both groups. Cells extracts prepared from SLE non-stimulated and stimulated PBMC contained a 11 KDa PRL immunoreactive material. Concentrated supernatants from SLE non-stimulated and stimulated PBMC contained both a 11 KDa and a 24-27 KDa PRL immunoreactive material. Our data indicate that PBMC from patients with SLE have an increased production of PRL-like immunoreactive material. This PRL is released in vitro as two different molecular weight forms, and appears to be derived from B rather than T lymphocytes.
Lupus 1995 Oct
PMID:Prolactin and systemic lupus erythematosus: prolactin secretion by SLE lymphocytes and proliferative (autocrine) activity. 856 28

Lysosome-associated membrane proteins (LAMPs) are transmembrane lysosomal glycoproteins which are detectable at the cell surface of lymphocytes in patients with scleroderma and systemic lupus erythematosus. While these proteins have been shown to mediate adhesion of tumor cells to vascular endothelial selectins, the function of LAMPs expressed at the cell surface of peripheral blood lymphocytes has not been previously examined. In the present study, the role of lamp2 (CD107b) in lymphocyte adhesion to vascular endothelium and the factors which influence in vitro cell surface expression of both lamp1 (CD107a) and lamp2 (CD107b) are examined. Freshly isolated PBMCs and unstimulated PBMCs in the culture had low levels of cell surface lamp1 and lamp2 expression which were significantly increased following PHA stimulation (P < 0.0001). A dose-dependent response to PHA and the effect of varying concentrations of serum were defined. Kinetic analysis revealed that the majority of the increase in both lamp1 and lamp2 occurred within the first 2 hr of incubation and that a subset of PBMCs maintained expression for at least 96 hr. Incubation of cells with colchicine and cycloheximide modified the cell surface expression of these proteins. Interleukins 2, 4, 6, and 8 had only a modest effect on the degree of cell surface lamp1 and lamp2 expression, though they did significantly affect the distribution of expression among different subtypes of lymphoid cells. Under the conditions utilized in this study, cell surface LAMP expression was confined primarily to CD56+ cells and to CD3+ cells. Functional analysis utilizing a fluorescence-based adhesion assay revealed that cell surface lamp2 mediates adhesion of PBMCs to vascular endothelium, possibly by interacting with endothelial selectins. LAMPs likely contribute to the migration of activated leukocytes to sites of inflammation in vivo.
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PMID:Lysosome-associated membrane proteins h-LAMP1 (CD107a) and h-LAMP2 (CD107b) are activation-dependent cell surface glycoproteins in human peripheral blood mononuclear cells which mediate cell adhesion to vascular endothelium. 866 Aug 32

We report on isolation of human polyclonal CD4-reactive antibodies of IgM and/or IgG isotypes from several SLE patients. These antibodies bound specifically to CD4-expressing cell lines and to rCD4 in ELISA and immunoblots. Saturation of CD4-binding sites occurred at antibody concentrations between 5 and 15 micrograms/ml. Anti-CD4 antibodies, in a dose-dependent manner, suppressed the proliferative responses of human peripheral blood mononuclear cells (PBMC) to superantigens (Staphylococcal enterotoxins A and B), anti-CD3 antibodies, and mitogens (PWM and Con A, but not PHA). They could also inhibit the proliferation of highly purified human T cells induced by immobilized anti-CD3 antibodies. To promote their effects on T cells, human anti-CD4 antibodies had to be present at lymphocyte cultures before or at the time of priming. There was no significant inhibition when antibodies were added more than 24 h following T cell activation. Substantial evidence that the immunosuppression induced by anti-CD4 antibodies was due to their direct effect on T cells was obtained. Down-regulatory effect of anti-CD4 antibodies could be significantly reversed by addition of exogenous IL-2 and by preincubation with soluble recombinant (r)CD4. Interestingly, at least one affinity-purified anti-CD4 antibody could costimulate the T cell proliferation induced by superantigens or anti-CD3 antibodies, especially when used at subsaturating concentrations (1-4 micrograms/ml) and when added subsequently to the initiation of cultures.
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PMID:Human CD4-reactive antibodies from SLE patients induce reversible inhibition of polyclonal T lymphocyte proliferation. 887 65

MRL/Mp-lpr/lpr (lpr) mice develop autoantibodies, vasculitis, and glomerulonephritis, which are similar to human systemic lupus erythematosus, and acquire a generalized, nonmalignant, lymphoproliferative disorder. CD4- CD8- CD3+ TCR alphabeta+ (double-negative, DN) T cells accumulate in spleen and lymph nodes, and become a major T cell population in vivo. These DN T cells, however, are refractory to various stimuli, including CD3, IL-2, CD28, PMA, and PHA. Recently, the lpr gene mutation has been identified as a mutant gene for Fas, resulting in expression defects of Fas Ag. It is still unclear, however, what kinds of mechanisms cause the dysfunction of lpr DN T cells. To elucidate the pathogenic mechanisms in abnormal DN T cells, biochemical analyses were conducted for the expression and tyrosine phosphorylation of the vav proto-oncogene product (Vav) in DN T cells from lpr mice. We demonstrated that Vav, a 95-kDa cytoplasmic protein, from lpr mice was constitutively tyrosine phosphorylated several times higher than in control +/+ mice, while expression of Vav protein in lpr and +/+ mice was equal. Additionally, in contrast with +/+ T cells, tyrosine phosphorylation of Vav, which normally increases within a minute of stimulation via TCR, did not increase in lpr DN T cells following PHA or Ab activation. Taken together with the suggested roles of Vav in multiple receptor-mediated signal transductions, our findings suggest that the functional abnormalities of lpr DN T cells may be related to Vav abnormal tyrosine phosphorylation, which could lead to impaired signaling between surface receptors and G proteins in this cell population.
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PMID:Constitutive tyrosine phosphorylation of the vav proto-oncogene product in MRL/Mp-lpr/lpr mice. 905 37

Antihypoxic drug olifen has been studied for effect in 72-hour PHA-stimulated cultures of blood lymphocytes in 15 healthy donors and 35 patients with diseases accompanied by enhanced mutagenesis in lymphocytes (rheumatoid arthritis, systemic lupus erythematosus, hypophyseal adenoma, neoplasms, chronic intoxications). Olifen has no mutagenic effect on mutagenesis in lymphocytes in a wide dose range. In diseases with intensive mutagenesis in lymphocytes olifen exhibits antimutagenic effect without lymphopoiesis.
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PMID:[Olifen action on mutagenesis in human lymphocytes]. 912 Oct 94


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