Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rheumatoid arthritis (RA) is a systemic autoimmune disease affecting 1% of the world's population, with significant morbidity and mortality. In this study, we investigated a recombinant adeno-associated virus (rAAV) vector for its potential application in RA gene therapy. rAAV encoding Escherichia coli beta-galactosidase was injected into rat joints which had already been induced into acute arthritis after local lipopolysaccharide (LPS) administration, and the efficiency of in vivo transduction was evaluated. We observed a striking correlation between vector transgene expression and disease severity in arthritic joints. The inflammatory reaction peaked at 3 to 7 days after LPS treatment, and, at the same time, 95% of the synoviocytes had high-level transgene expression. Gene expression diminished to the basal level (5%) when the inflammation subsided at 30 days after LPS treatment. More importantly, the diminished transgene expression could be efficiently reactivated by a repeated insult. The transgene expression in normal joints transduced with rAAV remained low for a long period of time (30 days) but could still be induced to high levels (95%) at 3 to 7 days after LPS treatment. This is the first demonstration of disease state-regulated transgene expression. These findings strongly support the feasibility of therapeutic as well as preventative gene transfer approaches for RA with rAAV vectors containing therapeutic genes, which are expected to respond primarily to the disease state of the target tissue.
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PMID:Disease-inducible transgene expression from a recombinant adeno-associated virus vector in a rat arthritis model. 1007 95

A polymorphism in the promoter of human NRAMP1 encodes a Z-DNA forming dinucleotide repeat with four alleles: (1) t(gt)5ac(gt)5ac(gt)11g; (2) t(gt)5ac(gt)5 ac(gt)10g; (3) t(gt)5ac(gt) ac(gt)9g; and (4) t(gt)5ac(gt)9g. Alleles 1 and 4 are rare (gene frequencies approximately 0.001); alleles 2 and 3 occur at gene frequencies approximately 0.20-0.25 and approximately 0.75-0.80, respectively. Here, luciferase reporter gene constructs are used to show that the four alleles differ in their ability to drive gene expression. In the absence of exogenous stimuli, alleles 1, 2, and 4 are poor promoters; allele 3 drives high expression, indicating that the repeat itself has endogenous enhancer activity. All four alleles show a similar percentage enhancement of reporter gene expression in the presence of interferon-gamma, consistent with the multiple interferon-gamma response elements both 5' and 3' of the Z-DNA forming repeat. However, while the addition of bacterial lipopolysaccharide (LPS) has no effect on alleles 1 and 4, it causes significant reduction in expression driven by allele 2 and enhances expression driven by allele 3, suggesting that the juxtaposition of LPS related response elements (NFkappaB, AP-1, NF-IL6) may be differentially affected by the two commonly occurring alleles. These results are consistent with the hypothesis that chronic hyperactivation of macrophages associated with allele 3 is functionally linked to autoimmune disease susceptibility, while the poor level of NRAMP1 expression promoted by allele 2 contributes to infectious disease susceptibility. Conversely, allele 3 protects against infectious disease and allele 2 against autoimmune disease. Hence, alleles that are detrimental in relation to autoimmune disease susceptibility may be maintained in the population because they improve survival to reproductive age following infectious disease challenge.
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PMID:Evidence for a functional repeat polymorphism in the promoter of the human NRAMP1 gene that correlates with autoimmune versus infectious disease susceptibility. 1022 96

Vesnarinone (OPC-8212) is a synthetic quinolinone derivative with inotropic and immunomodulatory effects. Vesnarinone has been shown to inhibit tumor necrosis factor-alpha (TNF alpha) produced by mitogen stimulated macrophages, and to inhibit phosphodiesterase (PDE) type III in cardiac muscle. TNF alpha and interferon-gamma (IFNgamma) have been implicated in the pathogenesis of autoimmune diseases, and both cytokines are targets for therapeutic intervention. IFNgamma can enhance autoimmune disease through direct effects, and indirectly by priming macrophages to produce TNF alpha. In this study, we demonstrate that while vesnarinone enhances basal TNF alpha levels, it inhibits TNF alpha production in peripheral blood mononuclear cells from multiple sclerosis (MS) patients and healthy donors stimulated with lipopolysaccharide (LPS) or primed with IFNgamma and stimulated with suboptimal doses of LPS. In addition, vesnarinone inhibited TNF alpha production in primary adult human microglial cultures. However, in contrast to rolipram, another TNF alpha inhibiting agent, vesnarinone failed to inhibit TNF alpha production by myelin basic protein specific T-cell lines. As oral TNF inhibitors are currently being considered in the USA for clinical application in MS, the implications of our findings on the development of vesnarinone for treatment of MS are discussed.
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PMID:The effect of vesnarinone on TNF alpha production in human peripheral blood mononuclear cells and microglia: a preclinical study for the treatment of multiple sclerosis. 1040 67

1. We investigated the role of bacterial lipopolysaccharide (LPS) in the reactivation of autoimmune disease by using collagen-induced arthritis (CIA) in mice in which autoimmunity to the joint cartilage component type II collagen (CII) was involved. 2. CIA was induced by immunization with CII emulsified with complete Freund's adjuvant at the base of the tail (day 0) followed by a booster injection on day 21. Varying doses of LPS from E. coli were i.p. injected on day 50. 3. Arthritis began to develop on day 25 after immunization with CII and reached a peak on day 35. Thereafter, arthritis subsided gradually but moderate joint inflammation was still observed on day 50. An i.p. injection of LPS on day 50 markedly reactivated arthritis on a dose-related fashion. Histologically, on day 55, there were marked oedema of synovium which had proliferated by the day of LPS injection, new formation of fibrin, and intense infiltration of neutrophils accompanied with a large number of mononuclear cells. The reactivation of CIA by LPS was associated with increases in anti-CII IgG and IgG2a antibodies as well as various cytokines including IL-12, IFN-gamma, IL-1beta, and TNF-alpha. LPS from S. enteritidis, S. typhimurium, and K. neumoniae and its component, lipid A from E. coli also reactivated the disease. Polymyxin B sulphate suppressed LPS- or lipid A-induced reactivation of CIA. 4. These results suggest that LPS may play an important role in the reactivation of autoimmune joint inflammatory diseases such as rheumatoid arthritis in humans.
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PMID:The role of lipopolysaccharide injected systemically in the reactivation of collagen-induced arthritis in mice. 1074 85

Although most published epidemiological studies have found little evidence of systemic autoimmune disease associated with silicone breast implants, there still remains a question of whether silicones can cause local and/or systemic immune dysfunction. This study further investigates the effects of silicones on autoantibody and immunoglobulin production and macrophage activation in female A.SW mice. Sixty mice were divided among four treatment groups receiving a 0.5-ml intraperitoneal injection of either phosphate-buffered saline (PBS), pristane, silicone gel, or silicone oil. Test bleeds were taken periodically for 6 months. In contrast to pristane, neither silicone gel nor silicone oil induced lupus-associated antinuclear autoantibodies (immunoglobulin G [IgG] anti-nRNP/Sm, Su, and ribosomal P) or lupus nephritis. However, serum IgM became elevated persistently within 1 month of silicone gel or silicone oil administration. Also, the level of IgG3 was clearly elevated in silicone oil-treated mice. In contrast, IgG1, IgG2a, and IgG2b levels were not affected greatly by either silicone gel or oil. Furthermore, peritoneal macrophages from silicone- and pristane-treated mice produced higher levels of interleukin-1beta (IL-1beta) and IL-6 than those from PBS-treated mice after lipopolysaccharide stimulation. These results suggest that silicone gels and oils are capable of inducing hypergammaglobulinemia and activating macrophages in female A.SW mice.
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PMID:Induction of hypergammaglobulinemia and macrophage activation by silicone gels and oils in female A.SW mice. 1079 47

In systemic autoimmune-prone (NZB x NZW)F1 (NZB/W F1) mice, B-cell abnormalities characterized by hypergammaglobulinaemia accompanying autoantibodies have been thought to be a main cause of the disease. To examine a possible regulatory role of B cells in the disease manifestations, we injected, intravenously (i.v.), normal or autoimmune B cells into non-irradiated NZB/W F1 mice. The injection of splenic B cells from major histocompatibility (MHC)-matched or allogeneic normal mice caused a marked decrease in serum immunoglobulin G (IgG) levels of autoantibodies, delayed the appearance of proteinuria and prolonged life span, whereas treatment with splenic B cells from NZB/W F1 or X-linked immunodeficient (Xid) mice failed to suppress the autoimmunity. Moreover, in vitro polyclonal antibody responses to lipopolysaccharide (LPS) of NZB/W F1-derived B cells from the treated mice were markedly reduced. Interestingly, the treatment of NZB/W F1 mice at 16, 18 and 20 or at 20, 22 and 24 weeks of age was more effective than that at 6, 8 and 10 weeks. The treatment also inhibited the development of surface IgG+ (sIgG+) B cells and splenomegaly, prominent in aged NZB/W F1 mice. In addition, when untreated NZB/W F1 responding B cells were precultured with normal B cells in vitro for 3 days, they also diminished the autoantibody production to subsequent LPS stimulation. Hence, the present results imply a novel function of normal B cells to ameliorate autoimmune disease in NZB/W F1 mice by correcting their B-cell abnormalities, and indicate that NZB/W F1 and Xid mice possess defects in this regulatory B-cell function.
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PMID:A novel function of B lymphocytes from normal mice to suppress autoimmunity in (NZB x NZW)F1 mice. 1080 65

We and others recently reported tumor necrosis factor (TNF) and apoptosis ligand-related leukocyte-expressed ligand 1 (TALL-1) as a novel member of the TNF ligand family that is functionally involved in B cell proliferation. Transgenic mice overexpressing TALL-1 have severe B cell hyperplasia and lupus-like autoimmune disease. Here, we describe expression cloning of a cell surface receptor for TALL-1 from a human Burkitt's lymphoma RAJI cell library. The cloned receptor is identical to the previously reported TNF receptor (TNFR) homologue transmembrane activator and calcium modulator and cyclophilin ligand (CAML) interactor (TACI). Murine TACI was subsequently isolated from the mouse B lymphoma A20 cells. Human and murine TACI share 54% identity overall. Human TACI exhibits high binding affinities to both human and murine TALL-1. Soluble TACI extracellular domain protein specifically blocks TALL-1-mediated B cell proliferation without affecting CD40- or lipopolysaccharide-mediated B cell proliferation in vitro. In addition, when injected into mice, soluble TACI inhibits antibody production to both T cell-dependent and -independent antigens. By yeast two-hybrid screening of a B cell library with TACI intracellular domain, we identified that, like many other TNFR family members, TACI intracellular domain interacts with TNFR-associated factor (TRAF)2, 5, and 6. Correspondingly, TACI activation in a B cell line results in nuclear factor kappaB and c-Jun NH(2)-terminal kinase activation. The identification and characterization of the receptor for TALL-1 provides useful information for the development of a treatment for B cell-mediated autoimmune diseases such as systemic lupus erythematosus.
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PMID:TACI is a TRAF-interacting receptor for TALL-1, a tumor necrosis factor family member involved in B cell regulation. 1088 May 35

Mannose-binding lectin (MBL) is an important constituent of the innate immune system. This protein binds through multiple lectin domains to the repeating sugar arrays that decorate many microbial surfaces, and is then able to activate the complement system through a specific protease called MBL-associated protease-2. We have used flow cytometry to study both the binding of MBL to microorganisms and the subsequent activation of complement. For selected Gram-negative organisms, such as Salmonella and Neisseria, we have examined the relative roles of lipopolysaccharide (LPS) structure and capsule in determining binding and conclude that the LPS is of major importance. Our results from studies with several clinically relevant organisms also show that MBL binding detected by flow cytometry leads to measurable activation of purified C4, suggesting that the bound lectin is capable of initiating opsonophagocytosis and/or bacterial lysis. There is an increasing literature suggesting that MBL deficiency, which mainly results from three relatively common single point mutations in exon 1 of the gene, predisposes both to infection by extracellular pathogens and to autoimmune disease. In addition, the protein also modulates disease severity, at least in part through a complex, dose-dependent influence on cytokine production. The mechanisms and signalling pathways involved in such processes remain to be elucidated.
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PMID:Mannose-binding lectin: targeting the microbial world for complement attack and opsonophagocytosis. 1141 67

Programmed cell death (apoptosis) is an essential process in the development of various tissues and its involvement has been proposed for the elimination of self-reactive immature T and B lymphocytes when self antigens are first encountered. In order to further investigate the role of apoptosis in the pathogenesis of autoimmune disease, the apoptosis of lipopolysaccharide (LPS)-activated B cells, peritoneal cells from NZB x NZW F1 (NZB/W F1) mice and nonautoimmune BALB/c mice were assayed using an in vitro culture system. Splenic B cells were isolated and then stimulated with LPS before further activated with crosslinking antimu antibody. In addition, the apoptosis of peritoneal cells induced by crosslinking antimu antibody was also analyzed. The data revealed that the specific apoptosis of both activated B cells and peritoneal cells induced by crosslinking antimu antibody was very similar comparing NZB/W F1 and nonautoimmune BALB/c mice. This activation-induced B-cells apoptosis could be rescued, however, with the addition of cytokines such as interleukin (IL)-5 or IL-10, to the culture. The results suggest that there is no endogenous defect in the apoptosis of activated B cells for autoimmune NZB/W F1 comparing nonautoimmune BALB/c mice. Notably, however, abnormally high levels of the type 2 T helper (Th2)-related cytokines such as IL-5 or IL-10 may play an important role in the abnormal expansion of activated B cells in autoimmune NZB/W F1 mice.
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PMID:The effect of cytokines on the activation-induced apoptosis of B cells in autoimmune NZB x NZW F1 mice. 1142 8

Serum amyloid P component (SAP) is a major acute-phase reactant in mice. Recently, it was reported that SAP-deficient mice spontaneously developed anti-nuclear antibodies and severe glomerulonephritis. Because the SAP-deficient mice we generated display no obvious phenotypic abnormalities, we investigated whether our SAP-deficient mice would also spontaneously develop autoimmune responses. In accordance with the report, our mice produced high titers of anti-nuclear antibody but did not develop severe glomerulonephritis. On the other hand, it was recently reported that SAP bound to gram-negative bacteria via lipopolysaccharide (LPS) prevented LPS-mediated activation of a classical complement pathway. Thus, we asked if SAP-deficient mice would show altered responses to an intraperitoneal injection of LPS from Salmonella typhimirium. SAP-deficiency did afford resistance to lethality induced by high-dose LPS. Our experiments clearly showed that contrary to documented data, SAP-deficient mice do not develop serious autoimmune disease and we suggest that SAP has a critical role in LPS toxicity.
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PMID:Mice lacking serum amyloid P component do not necessarily develop severe autoimmune disease. 1148 29


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