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)

We have found a human serum, E27, obtained from a multiply transfused patient with systemic lupus erythematosus, which immunoprecipitates the lymphocyte function associated antigen-1 (LFA-1). The immunoprecipitated molecules were identified as the LFA-1 alpha and beta chains by their comigration on SDS-PAGE, two-dimensional SDS-PAGE, and by sequential clearance experiments. Serum E27 did not immunoprecipitate LFA-1 from autologous cells, though LFA-1 molecules were present. In contrast, serum E27 immunoprecipitated LFA-1 from most but not all normal donor lymphocytes. Thus, serum E27 defines two serological phenotypes of LFA-1. 95% of normal individuals tested exhibited the LFA-1 phenotype precipitated by serum E27. Serum E27 appears to be directed at determinants of the LFA-1 alpha-chain and not the beta-chain since it immunoprecipitated LFA-1 molecules but not the Mac-1 molecules. Additional evidence for the alpha chain specificity was provided by immunoprecipitation of mouse-human heterohybridoma cells. LFA-1 was immunoprecipitated by serum E27 from mouse-human heterohybridoma cells expressing the human alpha-chain, not from a hybrid cell line expressing the human beta-chain. Together these findings demonstrate an antigenic polymorphism of the human LFA-1 alpha-chain molecule.
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PMID:Polymorphism of lymphocyte function-associated antigen-1 demonstrated by a lupus patient's alloantiserum. 243 4

Our understanding of the immune mechanisms that lead to systemic lupus erythematosus has been greatly advanced by the availability of murine models which display both serological and clinical features of the human disease. Studies have demonstrated that CD4+ T cells are required for the full expression of disease in these mice. (NZB X NZW)F1 mice exhibit a lupus-like disease (elevated levels of IgG antinuclear antibodies and a fatal glomerulonephritis) that is not characteristic of either parent. At least three gene loci have been identified in NZW mice that could potentially contribute to a T cell-dependent autoimmune disease, including the T cell receptor alpha- and beta-chain gene complexes and the major histocompatibility complex (MHC). The NZW T cell receptor beta-chain complex appeared to be particularly unusual in that the C beta 1, D beta 2, and J beta 2 gene segments have been deleted. However, an analysis of (NZB X NZW)F1 X NZB back-cross mice revealed no association of disease expression with the presence of this allele. There was also no correlation of disease incidence with the presence of the NZW T cell receptor alpha-chain allele. In contrast, nearly 90% of the backcross mice with the NZW MHC expressed severe autoimmune disease compared with 12% of the mice that did not carry this haplotype. Additional studies strongly suggested that the gene(s) within the NZW MHC is the only dominant NZW genetic contribution to F1 disease. We also determined if self-reactive T cells are able to escape thymic tolerance in autoimmune New Zealand and MRLlpr/lpr mice. In nonautoimmune mice expressing I-E, T cells utilizing V beta 17a and V beta 11 encoded domains have been shown to be clonally eliminated in the thymus. Similarly, V beta 8.1+ and V beta 6+ T cells are tolerized in nonautoimmune mice expressing Mls-1a. These T cell subsets were quantified in the lymph nodes and spleens of (NZB X NZW)F1, (NZB X SWR)F1, and MRL-lpr/lpr mice before and after the development of lupus-like disease. The results indicate that peripheral T cells in these mice, including the massive CD4-, CD8- T cell population in lpr mice, have been modified by normal mechanisms of tolerance such that potential self-reactive V beta specificities have been eliminated in the thymus.
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PMID:Self-reactive T cells in murine lupus: analysis of genetic contributions and development of self-tolerance. 257 38

In contrast to parental New Zealand Black (NZB) or New Zealand White (NZW) mice, (NZB x NZW)F1 mice exhibit a lupus-like disease characterized by high levels of immunoglobulin G (IgG) antinuclear antibodies in their serum and a fatal immune-complex glomerulonephritis. At least three gene loci have been identified in NZW mice that could potentially contribute to a T cell-dependent autoimmune disease, including the T cell receptor alpha- and beta-chain gene complexes and the major histocompatibility complex (MHC). The NZW T cell receptor beta-chain complex appeared to be particularly unusual in that the C-beta-1, D-beta-2, and J-beta-2 gene segments have been deleted. Approximately one half of (NZB x NZW)F1 x NZB backcross mice developed severe renal disease and elevated levels of IgG antibodies to double-stranded deoxyribonucleic acid and histone, suggesting that only one dominant gene or closely linked group of genes accounts for the NZW genetic contribution to F1 disease. Despite the extremely unusual nature of the NZW T cell receptor beta-chain gene complex, we found no association of disease expression with the presence of this allele in the backcross mice. There was also no correlation of disease incidence with the presence of the NZW T cell receptor alpha-chain allele. In contrast, nearly 90 percent of the backcross mice with the NZW MHC expressed severe autoimmune disease compared with 12 percent of the mice that did not carry this haplotype. Thus, the NZW MHC or gene(s) linked to this locus appears to be the only dominant NZW genetic contribution to F1 disease. Recent preliminary studies mapping genes that are located centromeric and telomeric to the NZW MHC suggest that the disease-associated gene(s) lies within the MHC.
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PMID:Genetic contributions to lupus-like disease in NZB/NZW mice. 326 57

The mRNA expression of interleukin (IL)-2, IL-2 receptor-alpha-chain (IL-2R alpha), IL-4 and interferon-gamma (IFN-gamma) in spleen cells from NZB/NZW F1) mice following the stimulation with concanavalin A (Con A) was examined by Northern blot analysis. Kinetic patterns of the mRNA expression after the stimulation were not different between 2-month-old and 6 to 8-month-old B/W F1 mice. However, relative mRNA expression of IL-2 to a cytoskeletal protein, alpha-Tubulin was lower in 6 to 8-month-old B/W F1 mice than in 2-month-old mice. Similar but not significant tendency was observed in IL-2R mRNA expression. In contrast, Relative IL-4 mRNA expression in 6 to 8-month-old B/W F1 mice was significantly higher than that in 2-month-old animals. On the other hand, no apparent change was observed in IFN-gamma mRNA expression. Flow cytometric analysis indicated that there was no apparent difference in proportion of L3T4 positive T cells in spleen cells from 2 and 6 to 8-month-old B/W F1 mice. These results suggest that mRNA expression of IL-2 and IL-4 differentially changes with aging in autoimmune B/W F1 mice.
Lupus 1995 Jun
PMID:Age-related differential mRNA expression of T cell cytokines in NZB/NZW F1 mice. 765 92

The production of pathogenic anti-DNA autoantibodies in mice with lupus nephritis is dependent on special autoimmune Th cells that can also transfer the disease into preautoimmune mice. In previous work, these pathogenic Th cells were cloned and their TCR beta-chains were sequenced to reveal a recurrent motif of anionic residues in their CDR3 loops. Accordingly, approximately half of the Th clones were found to be specific for nucleosomal Ag that contain cationic residues. Herein, we analyzed the TCR alpha-chain repertoire of 15 of these pathogenic Th clones and found them to be heterogeneous, even among the nucleosome-specific Th clones. Most of these autoimmune TCR alpha-chains contained anionic residues in their CDR3 in addition to cationic residues. Therefore, these pathogenic Th clones of lupus probably recognize epitopes with mixed charge runs that are derived from autoantigens, such as histone-DNA complexes. Interestingly, the V alpha gene segments used by 10 of these Th clones derived from the (SWR x NZB)F1 lupus mice differed from previously reported sequences indicating that they were new members or alleles of the respective V alpha gene family. One of the Th clones used a gene from an entirely new murine V alpha gene family, identified here as V alpha 23, which consisted of approximately two members that were conserved among strains with different V alpha haplotypes. Knowledge of the primary structure of the TCR expressed by these pathogenic Th clones of lupus would help in the analysis of their antigenic specificities and also would be essential for studying their regulation in transgenic mice carrying these autoimmune TCR genes.
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PMID:T cell receptor alpha-chain repertoire of pathogenic autoantibody-inducing T cells in lupus mice. 830 Nov 46

Soluble transferrin receptors (sTfR) were detected in culture supernatants of activated human peripheral blood mononuclear cells (PBMC) using a sandwich ELISA technique with two non-cross-reacting TfR MoAbs. Mitogenic stimulation of lymphoid cells induced both up-regulation of TfR surface density and release of sTfR to the medium. Peak levels of sTfR in culture supernatants occurred at day 4 after activation, 1 day later than maximum expression of TfR in the plasma membrane. Production of sTfR was independent of proliferation, as demonstrated by measuring sTfR release by PBMC, which had been irradiated with a dose of 20 Gy before activation. In addition to these in vitro experiments, we tested the sera of 85 patients with systemic lupus erythematosus (SLE), an autoimmune disease accompanied by in vivo activation of lymphocytes, for their sTfR levels. No correlation of these data was detectable to serum concentrations of the soluble alpha-chain of the IL-2 receptor, an unequivocal marker of lymphocyte activation. However, they correlated negatively to the haemoglobin content of the patients' erythrocytes, indicating that erythroid progenitors are the predominant source of sTfR in SLE patients' sera.
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PMID:A soluble form of the human transferrin receptor is released by activated lymphocytes in vitro. 851 87

Recent understanding of the mechanism of immunoglobulin G (IgG) catabolism has yielded new insight into antibody-mediated diseases. We proposed that beta2-microglobulin (beta2m)-deficient mice have been protected from systemic lupus erythematosis (SLE)-like syndromes because they lack the beta2m-associated IgG protection receptor (FcRn) and therefore catabolize IgG, including pathogenic IgG autoantibodies, considerably more rapidly than normal mice. Such an hypothesis would predict that beta2m-deficient mice would also be resistant to experimental bullous pemphigoid, a disease with a pathogenesis thought to be much simpler than SLE, being the result of antibody directed toward a pathogenic epitope on the epidermal hemidesmosome that anchors basal keratinocytes to the basement membrane. To test this hypothesis, we administered pathogenic rabbit antibody directed toward the hemidesmosome to beta2m-deficient mice and to normal control mice, both intraperitoneally and intradermally, and assessed the mice clinically, histologically, and immunologically for manifestations of skin disease. We found that the beta2m-deficient mice were protected when the antibody was given intraperitoneally whereas intradermal administration resulted in blisters only slightly less severe than those seen in normal mice. These data would indicate that autoantibody-mediated inflammation might be prevented or controlled by appropriate modulation of FcRn function.
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PMID:Beta2-microglobulin-deficient mice are resistant to bullous pemphigoid. 927 93

The goal of this study was to determine whether class I proteins play an important role in the regulation of Ig and to elucidate the mechanism(s) involved. We analyzed the phenotype imposed by a null allele of beta 2-microglobulin (beta 2m). Serum Ig levels of several mouse strains showed a beta 2m dependence that was most evident in mice genetically predisposed to develop chronic systemic lupus erythematosus, was preferential to IgG isotypes, and was greatly exaggerated in aging mice that normally develop hypergammaglobulinemia. Beta 2m-deficient mice, regardless of genetic background, also displayed a substantial reduction of specific Ab in response to a prototypic T cell-dependent Ag and a prototypic T cell-independent 2 Ag. This reduction could be accounted for by a selective diminution of Abs of the IgG class. Therefore, class I proteins play a considerable role in the regulation of Ig. The beta 2m dependence could not be explained by class I-dependent immunoregulatory cells (CD8+ cells, NK1.1+ T cells, or conventional NK+ cells) or by the transfer of maternal IgG into the prenatal/neonatal mouse made possible by the beta 2m-dependent Fc receptor (FcRn). However, a beta 2m-dependent increase in the half-lives of IgG, presumably conferred by lifelong FcRn expression, was observed in all mice regardless of genetic background and age. We conclude that FcRn-mediated protection of IgG from catabolism is a generic mechanism that best explains the lifelong beta 2m dependence of Ig in both normal and pathologic situations.
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PMID:Beta 2-microglobulin-deficient mice are protected from hypergammaglobulinemia and have defective antibody responses because of increased IgG catabolism. 936 2

Anti-C1s autoantibodies (IgG forms), which recognize the conjunction of C1s heavy chain and light chain (C1s-presenting autoantibodies) from patients with systemic lupus erythematosus (SLE), have been found to stimulate C1s enzymatic activities. This is due to acceleration of the proteolytic hydrolysis of the synthetic substrate C1-1 by C1s, enhancement of the complex formation of C1s with its natural pseudosubstrate, C1 inhibitor (C1 inh), and promotion of proteolytic activation of its natural substrate, C4. Seven of fifteen samples from patients with SLE were found to contain such autoantibodies. The hydrolysis of the synthetic substrate C1-1 catalyzed by C1s in 25 to 27 min in the presence of anti-C1s autoantibodies was equivalent to the hydrolysis of C1-1 catalyzed by C1s alone or C1s with control IgG from healthy sera in 110 min, approximately fourfold faster than the reaction in the absence of anti-C1s autoantibodies. Densitometry scanning data showed that the formation of the C1s-C1 inh complex in the presence of anti-C1s autoantibodies was three to four times greater than that with control IgG. It was also noticed that the autoantibodies convert almost all of the latent forms of C1s to an active form that binds to C1 inh. Another group of Western blots showed that C1s cleaved C4 alpha-chain three times faster in the presence of autoantibodies than of control IgG. It is likely that the overconsumption of complement components is common in the pathogenesis of tissue damage occurring in SLE.
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PMID:In vitro stimulation of C1s proteolytic activities by C1s-presenting autoantibodies from patients with systemic lupus erythematosus. 957 73

The expression of a transgenic encoding the I-E alpha-chain, Ea(d), is highly effective in the protection from systemic lupus erythematosus (SLE) in BXSB and (MRL x BXSB)F1 male mice, in which a mutant gene, Yaa (Y-linked autoimmune acceleration), plays a critical role. To gain further insight into the protective role of the Ea(d) transgene, we compared the effect of the transgene in two additional lupus-prone (NZB x BXSB)F1 and (NZW x BXSB)F1 hybrid mice, in which both F1 female mice develop typical SLE in the absence of the Yaa gene and their F1 males bearing the Yaa gene develop a more accelerated form of SLE. Comparative analysis of the clinical development of SLE in these F1 hybrid mice showed that Ea(d) transgene expression was much more effective in the protection from SLE occurring in the F1 females than in their male counterparts. Our results indicate that the Ea(d) transgene is capable of preventing SLE by inhibiting autoimmune responses, independently of the Yaa gene-accelerating effect, and that its protective capacity is strongly influenced by the genetic susceptibility to SLE in individual strains of lupus-prone mice. In addition, this autoimmune inhibitory effect was shown to be selective for IgG, but not IgM, anti-DNA autoantibody production, and is more specific for anti-gp70 autoantibody than for anti-DNA autoantibody. These results favour the hypothesis that the transgene expression may lead to the modulation of self-peptide presentation, thereby preventing excessive T-cell-dependent activation of autoreactive B cells.
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PMID:Effect of genetic background on Ea(d) transgene-mediated protection from murine lupus. 969 72


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