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)

Both normal and autoimmune mice have IgM natural autoantibodies to bromelain-treated erythrocytes in which phosphatidylcholine (PTC) becomes exposed. At one stage this antibody may participate in the genesis of autoimmune hemolytic anemia in the NZB mouse. We have recently studied a patient with hemolytic anemia who had persistently high serum titers of IgM anticardiolipin antibodies (aCL) that were also demonstrated in a hemolysate of his erythrocytes obtained at the time of the anemia. We affinity-purified the antibody and sought its binding to normal human bromelain-treated erythrocytes (BrE) because of the IgM isotype of the antibody, since cardiolipin is not a constituent of the erythrocyte wall, and because the anionic phospholipids, with which aCL are known to cross-react, are not located at the outer leaflet of the erythrocyte membrane. We found binding of the antibody to HBrE in their hemolysates and by flow cytometry. We also demonstrated that the aCL cross-reacted extensively with PTC, as well as with other anionic or zwitterionic phospholipids. The purified IgM antibody lysed BrE in the presence of complement and also bound to in vitro-aged erythrocytes. Because this patient had no other evidence of systemic lupus erythematosus or any other autoimmune condition, his disease may represent a variant of the recently described primary antiphospholipid syndrome.
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PMID:Hemolytic anemia related to an IgM autoantibody to phosphatidylcholine that binds in vitro to stored and to bromelain-treated human erythrocytes. 208 93

Autoimmune MRL-lpr/lpr and NZB/W mice spontaneously secrete large quantities of pathogenic IgG1 and IgG2a autoantibodies. NZB mice also produce autoantibodies but these tend to be of the IgM H chain class. This work examines whether differences in the isotype of autoantibody produced by lupus-prone mice reflects differences in the sensitivity of autoreactive B cells to lymphokine-mediated IgG secretion. Twenty-five percent of normal BALB/c B cells produced IgG1 when stimulated in vitro with IL-4 plus LPS. This was comparable with the effect of IL-4 on small resting B cells from MRL-lpr/lpr and NZB/W mice. In contrast, less than 8% of the resting B cells from NZB mice produced IgG1 under these conditions. LPS plus IFN-gamma induced 5% of BALB/c and NZB/W but only 1% of NZB B cells to secrete IgG2a. Because lymphocytes from both young and old NZB mice showed diminished IgG1 and IgG2a secretion after lymphokine treatment, B cells from this strain appeared to be intrinsically resistant to the effects of IL-4 and IFN-gamma. In contrast, a disproportionately large proportion (22%) of B cells from adult MRL-lpr/lpr mice produced IgG2a when treated with IFN-gamma in vitro. Only B cells from MRL-lpr/lpr mice with active disease responded with such high levels of IgG2a production: cells from animals that had not yet developed clinical disease produced normal levels of IgG2a. Within each strain, B cells producing antibodies against autoantigens such as DNA, bromelain-treated mouse RBC and Sm responded to treatment with IL-4 and IFN-gamma in a manner indistinguishable from B cells producing antibodies against conventional Ag such as TNP and ARS.
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PMID:IgG1 and IgG2a production by autoimmune B cells treated in vitro with IL-4 and IFN-gamma. 210 5

The influence of dietary fat on autoimmunity in lupus-prone (NZB x NZW)F1 mice has been demonstrated. In defining further the effects of dietary lipid on the immune system of this strain, female weanling mice were placed on four diets differing in quantity and type of fat. Their immunologic response was then studied by a variety of tests at 4 and 7 mo of age. Few differences were seen among the four groups at 4 mo of age. At 7 mo of age, however, the mice receiving diets high in saturated and unsaturated fats had a reduced mitogenic response to T cell mitogens and an enhanced response to the B cell mitogen LPS. Immunoglobulin levels and delayed hypersensitivity responses did not show any consistent differences among the diet groups. At 7 mo, however, mice receiving diets high in unsaturated fat demonstrated hyperresponsiveness to injected sheep red blood cells as measured by the hemolytic plaque technique. In addition, peritoneal leukocytes from the same diet group exhibited an increased response to bromelain-treated autologous erythrocytes which was decreased after treatment with anti-Thy-1 antiserum and complement. Phagocytosis by peritoneal macrophages was significantly decreased in the animals fed high-fat diets, particular high saturated fat. Similarly, natural killer cell activity was markedly reduced in the mice with a high intake of saturated lipid, a finding which correlated with the in vitro production of interferon. These results indicate that diets high in fat influence immune responses and thus can affect the onset and severity of autoimmune disease. A low-fat diet can reduce the development of disease by maintaining normal immune responses. The data also suggest that unsaturated fat may influence T helper cell activity and therefore antibody production, whereas saturated fats may affect cellular immune responses which are dependent on membrane contact.
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PMID:Dietary fat and immune function. I. Antibody responses, lymphocyte and accessory cell function in (NZB x NZW)F1 mice. 241 89

We demonstrated previously that B151K12 T cell hybridoma produces two distinct B cell differentiation factors, B151-TRF1 and B151-TRF2, capable of inducing differentiation of antigen-activated and unstimulated B cells into antibody-forming cells, respectively. In the present study we investigated the pathophysiologic relation of these factors with factors obtained from MRL/MP-lpr/lpr(MRL/lpr) mice and (C57BL/6 X DBA/2)F1 (BDF1) mice undergoing chronic graft-vs-host reaction (GVHR), representing a murine model of systemic lupus erythematosus with polyclonal B cell activation associated with the T cell hyperfunction. The functional and biochemical analyses revealed that B151-TRF2-like, but not B151-TRF1-like, activity was found in culture fluid supernatant (CFS) of lymphoid cells from MRL/lpr mice with lymphoproliferative syndrome. On the other hand, both B151-TRF1- and B151-TRF2-like activities were detected in CFS prepared from spleen cells of BDF1 mice undergoing chronic GVHR by the inoculation of parental DBA/2 spleen cells. Interestingly, spleen cells of BDF1 mice transferred with DBA/2 thymocytes preferentially elaborated B151-TRF1-like factor. Because BDF1 mice transferred with DBA/2 spleen cells but not with DBA/2 thymocytes developed a SLE-like syndrome exemplified by the appearance of Coombs' antibody and proteinuria, it seemed likely that production of B151-TRF2-like factor was closely associated with the onset of autoimmune disease. In fact, B151-CFS containing B151-TRF2 but not B151-TRF1 activity could induce a striking autoantibody production both in vivo and in vitro as detected by PFC responses of normal mice to bromelain-treated mouse red blood cells (BrMRBC). Moreover, it was demonstrated that in vitro anti-BrMRBC PFC responses induced by semipurified B151-TRF2 was markedly inhibited by addition of relevant anti-Ia antibody to the culture. Thus, the present study demonstrates that B151-TRF2 represents one of the B cell differentiation factors responsible for polyclonal B cell activation leading to autoantibody production.
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PMID:Polyclonal B cell activation by a B cell differentiation factor, B151-TRF2. III. B151-TRF2 as a B cell differentiation factor closely associated with autoimmune disease. 354 18

MRL/MP-lpr/lpr (MRL/lpr) mice are known to provide a good model for the study on the pathogenesis of systemic lupus erythematosus with massive involvement of abnormal T lymphocytes in the spleen and lymphonodes. However, a direct role of B cells of MRL/lpr mice in autoimmune responses is not clear until this time. In the present study, to investigate the characteristic of B cells of the mice, we tried to establish a B cell clone after hybridization between splenic B cells of these mice and 2.52 M, a HAT selective medium sensitive mutant B cell line in the presence of polyethylene glycol and dimethyl sulfoxide and examined its response to autoantigens. MRL27.4, a subclone of a resulting hybridoma, expressed IgM, B220, IKk, ICAM-1, and LEA-1 on the cell membrane as well as CD5 molecules by analysis with flow microfluorometory (FMF). Also, MRL27.4 was shown to exhibit rosette formation against blood cells treated with bromelain (Br-RBC) at a frequency of more than 95%, and to express DNA-receptor (DNA-R) on its surface by FMF analysis with biotin-labeled ssDNA. In contrast, the parental 2.52 M did not form rosettes with Br-RBC and the expression of DNA-R on the cell membrane of 2.52 M was significantly less compared with that of MRL27.4. Interestingly, MRL27.4 produced a high titer of IgM-anti-ssDNA antibodies and IL-6 after treatment with the purified RBC membrane or immobilized DNA. On the other hand, the parental 2.52 M neither produce IgM-anti-ssDNA antibodies nor IL-6 under the same conditions. The results suggest that MRL27.4 is an autoantigen reactive B cell clone derived from MRL/lpr mice and its surface DNA-R, by itself, function to autoantigens. In this process, there might be an autocrine network mediated by IL-6. In conclusion, MRL27.4 provides a good model for the study on the direct function of B cells of MRL/lpr mice during abnormal immune responses to autoantigens.
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PMID:[Functional analysis of an autoantigen reactive B cell clone derived from MRL/MP-lpr/lpr mice]. 912 24

Accumulating data suggest that endocrine disruptors affect not only the reproductive system, but also the immune system. We demonstrate here that endocrine disruptors including diethylstilbestrol (DES) and bisphenol-A (BPA) enhance autoantibody production by B1 cells both in vitro and in vivo. BWF1 mice, a murine model for systemic lupus erythematosus (SLE), implanted with Silastic tubes containing DES after orchidectomy developed murine lupus characterized by immunoglobulin G (IgG) anti-DNA antibody production and IgG deposition in the glomeruli in the kidney as well as those implanted with 17beta-estradiol (E2). Plaque-forming cells (PFC) producing autoantibodies specific for bromelain-treated red blood cells were significantly increased in mice implanted with DES and BPA. IgM antibody production by B1 cells in vitro was also enhanced in the presence of endocrine disruptors including DES and BPA. Estrogen receptor (ER) expression was upregulated in B1 cells in aged BWF1 mice that developed lupus nephritis. These results suggest that endocrine disruptors are involved in autoantibody production by B1 cells and may be an etiologic factor in the development of autoimmune diseases.
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PMID:Endocrine disruptors (environmental estrogens) enhance autoantibody production by B1 cells. 1516 99