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)

T cells from murine lupus strains manifest complex defects in interleukin 2 (IL 2) production and receptor expression. The capacity of B cells from such mice to utilize IL 2 as a growth factor has not been previously reported and is examined herein. Anti-Thy-1.2 plus complement-treated spleen cells from 6-8-week-old autoimmune MRL-lpr/lpr mice and from age and sex-matched immunologically normal CBA/J mice were cultured with lipopolysaccharide (LPS) for 36 h and analyzed for the expression of IL 2 receptors using the monoclonal antibody 7D4. The percentage of B cells expressing IL 2 receptors was comparable in MRL-lpr/lpr and CBA/J mice. In contrast to those from CBA/J, BALB/c and (BALB/c X NZW)F1 mice, LPS-stimulated B cells from MRL-lpr/lpr and from (NZB X NZW)F1 mice were capable of proliferating in response to IL 2. Fractionation of MRL-lpr/lpr B cells using Percoll gradient density separation demonstrated that the IL 2-responsive population consisted predominantly of large cells. In addition, unfractionated B cells from MRL-lpr/lpr mice were found to be substantially more responsive to IL 2 than those from CBA/J and BALB/c mice following activation with anti-immunoglobulin plus LPS. The hyper-responsiveness to IL 2 may be a consequence of the state of activation of autoimmune B cells and is of potential importance in the pathogenesis of systemic lupus erythematosus.
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PMID:Interleukin 2 is a proliferative signal for B cells from autoimmune mice. 309 46

Palmerston North (PN) mice spontaneously develop autoimmune disease resembling SLE. Because immune responsiveness has not been defined in this strain, a study was designed to assay primary splenic plaque-forming cell (PFC) responses to thymus-dependent (TD) and thymus-independent (TI) Ag. Initial surveys of PN mice inoculated with the TD Ag SRBC showed adequate production of IgM PFC, but small numbers of IgG PFC were developed with polyspecific antiserum. In contrast, H-2-compatible DBA/1 control mice gave the expected responses to SRBC (IgG plaques elevated twofold compared with IgM plaques). PN mice had the usual responses to Ag that are largely TI; both PN and DBA/1 mice had active IgM and modest IgG responses to TNP-LPS and TNP-Ficoll. Additional experiments determined that PN mice had similar patterns of defective IgG responses to several different TD Ag (SRBC, horse RBC, and DNP-keyhole limpet hemocyanin). In each instance, the usual predominance of IgG1 plaques was absent, and total numbers of plaques developed with antisera specific for IgG isotypes were suppressed. Defective PN IgG production was evident as early as 3 wk of age, was not influenced by aging to 43 wk, and was not corrected by increasing the antigenic challenge 10-fold. PN spleen cells treated with monoclonal anti-Thy-1.2 and C were injected with pools of DBA/1 T cells into 850-rad irradiated (DBA/1 x PN)F1 hybrids. These recipients expressed low IgG1 responses to SRBC, suggesting that the B cell-containing fraction that was not lysed by anti-Thy-1.2 transferred the PN defect. PN mice, which do not respond to TD Ag with active IgG production, contradict the proposal that autoimmunity is associated with hyper-responsiveness to TD and TI Ag.
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PMID:Defective primary and secondary IgG responses to thymic-dependent antigens in autoimmune PN mice. 328 33

Allele-specific monoclonal anti-I-A antibodies are capable of specifically suppressing the immune response to antigens under the control of the allele towards which the antibody is directed, without suppressing the response to antigens under the control of the alternative allele of the I-A alpha and beta chain genes in an F1 heterozygote. This phenomenon, which has been termed 'allele-specific immunosuppression', is antigen-specific, long-lasting and transferrable with Thy-1-positive spleen cells. This type of immunosuppression has been applied to animal models of autoimmune disease, in both homozygous and heterozygous animal models. Anti-I-A monoclonal antibodies are capable of preventing, suppressing and treating experimental allergic encephalomyelitis (EAE), of partially suppressing experimental autoimmune myasthenia gravis, and of preventing the onset of type I insulin-dependent diabetes in the BB/W diabetic rat. In addition, this type of immunotherapy has succeeded in almost completely suppressing nephritis in NZB X NZW F1 mice, which normally develop severe lupus-like nephritis. Significant toxicity, which may be due to anti-allotype antibodies, anti-idiotype antibodies, or to impurities in the monoclonal antibody preparations, has been encountered in the BB/W diabetic rat. In addition, attempts to extend these observations to EAE in the cynomolgus monkey have encountered significant mortality which appears to be attributable to the monoclonal antibody injections (anti-HLA-DR). The mechanism of this toxicity and means of circumventing it are currently under investigation. These results demonstrate the critical role of I-A molecules in the induction and continuance of the autoimmune process in these experimental animal models.
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PMID:Monoclonal anti-Ia antibody therapy in animal models of autoimmune disease. 331 1

MRL/Mp-lpr/lpr (MRL/l) mice are widely known as poor inducers of interleukin-2 (IL-2) and low responders to IL-2. It was reconfirmed that the spleen cells of MRL/l mice induced a small amount of IL-2 in vitro. In vivo experiments revealed that recombinant IL-2 (rIL-2) affected T cell subpopulations in MRL/l mice. rIL-2 decreased the numbers of Thy-1 and Lyt-1 positive cells and increased those of Lyt-23, Lyt-123 and Lyt-null cells in the thymus. It decreased the number of T cell subpopulations in the lymph nodes and spleen. These data disclosed that IL-2 might affect not only the development of T cells but also the movement of T cells among the immune organs. Some synthetic immunomodulators augmented and others suppressed or had no effect on IL-2 induction activity in the spleen of MRL/l mice. There was no correlation between the clinical efficacy of drugs on rheumatic disease and experimental IL-2 induction activity. rIL-2 and human peripheral T cell derived IL-2 (hIL-2) produced similar results in short term therapeutic experiments. When rIL-2 (1,000 U/mouse) or hIL-2 (equivalent dose) was given to MRL/l mice intraperitoneally, once a week, from 8 to 16 weeks of age, anti-double stranded DNA (dsDNA) antibody and anti-single stranded DNA (ssDNA) antibody titers had no changes. IL-2 had no effect on the renal lesions histopathologically. IL-2 induction activity was also assayed using spleen cells of the animals at the time of necropsy. The results showed that the mice treated with IL-2 had lower IL-2 induction activity than nontreated MRL/l mice. mice, an animal model for systemic lupus
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PMID:Interleukin-2 induction, response and therapy on murine lupus lesions in the MRL/l strain. 349 9

Naturally occurring thymocytotoxic autoantibodies (NTA) have been suggested to be the cause of thymic atrophy and T cell disorders in human and murine lupus. Definitive studies on NTA's role in the induction of SLE, however, have been lacking due to the lack of a pure source of NTA. Although it is clear that NTA are a heterogeneous group of antibodies, the nature of their antigens has remained obscure. We report the characteristics of a monoclonal NTA, designated SAG-3, which appears more reflective of the activities previously reported of serum NTA than other NTA-secreting clones. SAG-3 is an IgM autoantibody cytotoxic for 80 to 90% of thymocytes, 20 to 25% of splenic lymphocytes, 25 to 30% of lymph node cells, and less than 3% cortisol-resistant thymocytes, bone marrow, and fetal liver cells. SAG-3 is murine-specific without reactivity towards rat, hamster, or guinea pig, and appears very early in thymic development, on day 17 fetal thymocytes. SAG-3 is equally cytotoxic against several strains of mice, including both Thy-1.1 and Thy-1.2 allotypes, and the cytotoxicity is absorbed by brain but not liver cells. Reactive thymocytes occurred throughout the cortical regions of the thymus, indicating preferential affinity towards immature thymocytes. Although the serologic activities of SAG-3 suggest that Thy-1 alloantigen is its target, SAG-3 antigen is found to be distinct from Thy-1 and also from Lyt-1, Lyt-2, or L3T4 antigens. The binding of SAG-3 to thymocytes could be competitively inhibited by NTA-positive NZB sera.
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PMID:A peripheral and central T cell antigen recognized by a monoclonal thymocytotoxic autoantibody from New Zealand black mice. 354 29

Naturally occurring thymocytotoxic autoantibodies (NTA) have been described in both humans and mice with SLE. To define further the role of anti-thymic autoantibodies in murine lupus, we studied the cellular and molecular specificity of a spontaneous monoclonal NTA, designated TC-17, derived from a 4-mo-old New Zealand Black mouse. TC-17, an IgM autoantibody, has been shown previously to be unreactive with Lyt-1, Lyt-2, and L3T4 (T helper) antigens. We have shown further that it is also unreactive with Thy-1. TC-17 recognizes a new thymic antigen that appears to mark a distinct subpopulation of cortisol-sensitive cortical thymocytes. The antigen consists of a single glycoprotein chain with an apparent m.w. of 88,000. TC-17 shows reduced binding to thymocytes treated with tunicamycin, indicating either that glycosylation of TC-17 antigen is necessary for TC-17 to bind to it or that glycosylation is required for expression of the antigen on the cell surface. TC-17 uniquely reacts with two of 17 murine lymphoid tumor cell lines of intermediate cellular maturity. The thymocytotoxic activity of TC-17 is absorbed by single cell suspensions of murine stomach, small intestine, large intestine, kidney, and thymus. Moreover, the specific binding of TC-17 to gut tissue of normal and germfree mice can be demonstrated by indirect immunofluorescence, suggesting antigenic cross-reactions between thymic and gut tissue. TC-17 reacts with rat thymocytes as well as it does with murine cells, indicating moderate evolutionary conservation of the TC-17 antigen. The expression of this glycoprotein by a discrete thymocyte subset may prove to be a valuable probe for the study of murine T cell differentiation.
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PMID:Tissue localization and biochemical characteristics of a new thymic antigen recognized by a monoclonal thymocytotoxic autoantibody from New Zealand black mice. 392 16

BALB/c mice neonatally injected with (BALB/c X C57BL/6)F1 hybrid spleen cells develop host-versus-graft disease (HVGD) with immunopathological features characteristic of either systemic lupus erythematosus (SLE), or immunoblastic lymphadenopathy (IBL) in man. HVGD mice manifest polyclonal hypergammaglobulinemia with various autoantibodies, generalized lymphadenopathy, hepatosplenomegaly, immune complex glomerulonephritis and evolve in the end to malignant lymphoma. The necessary prerequisite for HVGD induction between donor and host can be summarized as follows: Histoincompatibilities in the H-2 region between donor and host are needed; predominant F1 donor cells needed for HVGD induction are, if not sole, steroid resistant, nylon wool nonadherent and Thy-1 positive T cells; the role of donor T cells is not only to present H-2 complex to the host, but also to interact with and proliferate in the host; strain differences are found for the susceptibility of HVGD induction in the host. It has been found that HVGD evolves to a malignant lymphoma of host T cell origin. The HVGD mouse model may, therefore, contribute to the understanding of the cell to cell interactions at work in the pathogenesis of IBL, as well as SLE, in man.
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PMID:Autoimmune disease and malignant lymphoma associated with host-versus-graft disease in mice. 408 49

The role of T cell immunity against nuclear antigens recognized by autoantibodies in human and murine systemic lupus is unclear. We have studied the T cell proliferative response to purified Sm nuclear antigen by measuring in vitro 3H-thymidine incorporation by MRL/Mp- +/+ lymph node cells primed with Sm in Freund's adjuvant. Sm-primed cells responded in a dose-dependent fashion when cultured in vitro with purified Sm. Absorption of the Sm with solid-phase anti-Sm IgG from either of two lupus patients ablated the response, whereas control absorptions with normal IgG had no effect. Furthermore, cells from mice primed with physicochemically purified Sm responded in vitro to affinity-purified antigen, and vice versa. Treatment of cells with either anti-Thy-1 or anti-Lyt-1 and C eliminated Sm-induced proliferation, whereas anti-Lyt-2 treatment resulted in enhanced responses. MRL/Mp- +/+ mice, which made no detectable anti-Sm antibodies in vivo, were nonetheless capable of generating Sm-reactive T cells. These results indicate that T cells can specifically recognize the Sm nuclear antigen. Such recognition may be of importance in the generation of antibodies to Sm and other nuclear antigens in vivo.
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PMID:T cell recognition of the Sm nuclear antigen: induction of T cell proliferative responses in MRL/Mp- +/+ mice. 612 3

The effect of neonatal thymectomy on the induction and/or modification of murine SLE disease was examined in several representative groups of mice with early-life SLE (MRL/Mp-lpr/lpr females, BXSB males, (NZB X W)F1 females, (NZW X BXSB)F1 males and females), late-life SLE (MRL/Mp-+/+ and BXSB females), and normal strains (BALB/c and C57BL/6 females). Our results indicated that thymectomy prevented disease only in the MRL/Mp-lpr/lpr SLE mice, and that this effect diminished as thymectomy was delayed beyond 3 wk post-natally. In the other SLE mice studied, neonatal thymectomy did not modify disease symptoms to any significant degree. Moreover, depletion of mature T cells from donor BXSB male bone marrow did not affect the expression of early-life SLE in thymectomized BXSB female recipients. Neonatal thymectomy did not induce SLE in normal mice. Of note, neonatal thymectomy did not completely deplete the Thy-1.2+ cell population, i.e., 10 to 15% remained in the spleens of the thymectomized mice. This incomplete T cell depletion, together with the previously demonstrated dependence on and hyperresponsiveness of BXSB and (NZB X W)F1 B cells to T helper cell-derived accessory signals, cast doubts on earlier conclusions that B cells from some SLE mice can autonomously proliferate and differentiate to autoantibody-secreting cells. It seems more appropriate to conclude that B cells from the various SLE mice vary in their degree of response to, and production of, T cell-derived helper signals, and thus in their expression of B cell hyperactivity and disease.
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PMID:The effect of thymectomy on lupus-prone mice. 614 69

In the studies reported here, we have analyzed the production and consumption of T cell growth factor, more recently termed interleukin 2 (IL-2), as well as some cell-mediated immune functions, in murine strains [MRL, BXSB, NZB, and (NZB x NZWF1] manifesting systemic lupus erythematosus (SLE)-like syndromes. Young (4-6 wk) or old (4-8 mo) autoimmune or normal mice were studied and compared with regard to the following T cell functions in vitro after stimulation with concanavalin A (Con A): (a) mitogenic response; (b) IL-2 levels in culture supernates; and (c) the ability to respond to and adsorb IL-2. In addition, proliferative activity in the allogeneic mixed leukocyte culture and frequency of alloreactive cytotoxic T lymphocyte precursors (CTLp) were analyzed in some of these strains. Reduced Con A-induced mitogenic responses and IL-2 production appeared at 3-6 wk of age in the early, severe SLE developing strains MRL-Mp-lpr/lpr (MRL/l) and male BXSB and progressed thereafter. Similar defects appeared at a later stage in MRL/Mp-+/+ and (NZB x NZW)F1 hybrid mice, which develop late disease. Detailed analysis of cells from the enlarged lymph nodes and spleens of older MRL/l mice demonstrated that such cells: (a) responded poorly to Con A or allogeneic stimulator cells, even in the presence of exogenous IL-2; (b) did not suppress IL-2 production by normal spleen cells; (c) were relatively incapable of adsorbing or inactivating IL-2; and (d) had a markedly reduced anti-H-2b CTLp frequency in the mesenteric lymph nodes but a normal one in spleen. These results indicate that the proliferating Thy-1.2+, Lyt-1+ T cells in MRL/l mice are defective in their responses to mitogenic stimuli, in IL-2 production, and in expression of acceptor sites for IL-2. The relevance of these defects to the MRL/l disease as well as to the role of IL-2 in autoimmunity in general remains to be determined.
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PMID:Analysis of T cell function in autoimmune murine strains. Defects in production and responsiveness to interleukin 2. 645 21


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