Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003873 (rheumatoid arthritis)
 53,068 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immune complexes were isolated from the synovial effusions of patients with seropositive definite or classical rheumatoid arthritis by centrifugation over a sucrose-polyethylene glycol gradient. Physiochemical and immunochemical analysis showed IgG and IgM to be the predominant molecular species with lesser amounts of Clq and moderate amounts of IgA and activated C4 and C3. Very low concentrations of Clr, Cls, factor B and beta 2-microglobulin were detected. Trace amounts of four other components totalling less than 4% of the total protein, were seen and their molecular weights established. Reasons were advanced for thinking that fibrinogen, human serum albumin and alpha 2-macroglobulin were only secondarily associated with the complexes. The data are consistent with the hypothesis that IgG is the main, if not the only antigen, responsible for provoking and maintaining the pathological changes in rheumatoid arthritis.
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PMID:Analysis of immune complexes in synovial effusions of patients with rheumatoid arthritis. 738 2

Total plasma zinc levels in patients with rheumatoid arthritis on different therapeutic treatments were determined in conjunction with total serum proteins, serum albumin and globulin, and articular index of joint tenderness, erythrocyte sedimentation rate, rheumatoid factor, serum copper, and serum iron. There were significantly lower zinc levels in patients with rheumatoid arthritis on nonsteroidal anti-inflammatory drugs than in patients on levamisole and penicillamine. Zinc levels correlated positively with serum albumin, and there was an inverse correlation between zinc levels and both ESR and globulin concentration in all rheumatoid patients. However, the correlation coefficient varied in the different treatment groups. The results of this study support the hypothesis that low plasma zinc level in rheumatoid arthritis is one of the nonspecific features of inflammation.
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PMID:Plasma zinc and its relationship to clinical symptoms and drug treatment in rheumatoid arthritis. 743 58

Adjuvant-induced arthritis in rats is a chronic inflammatory disease, widely used as an animal model for rheumatoid arthritis. In our study the effect of various fractions of dialyzable leukocyte extract (DLE): DLE I-molecular weight below 10 kDa (commercial preparation), DLE II-molecular weight below 5 kDa (suppressor fraction), DLE III-molecular weight 5-10 kDa on rat adjuvant-induced arthritis was studied. The adjuvant arthritic (AA) rats were treated with DLE fractions i.p. in solutions containing an active substance isolated from 12.5 x 10(6) and 6.25 x 10(6) leukocytes from day 1 (adjuvant injected) through day 18, every second day (total 9 times). Various markers of inflammation, immune function and joint destruction were evaluated: hindpaw volume, serum hyaluronic acid, serum albumin and biopterin in urine. All these markers showed a significant improvement after using fraction DLE II in comparison with AA controls. Fractions DLE I and DLE III influenced only some markers of inflammation and immune function. Our results demonstrated a therapeutical effect of fraction DLE II on rat adjuvant-induced arthritis.
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PMID:Influence of various forms of dialyzable leukocyte extracts on rat adjuvant arthritis. 748 70

We have purified HLA-DR from the spleen of a patient with rheumatoid arthritis. The patient had Felty's syndrome and was heterozygous for the DR4Dw4 antigen. We have isolated endogenous peptides from purified HLA-DR molecules. The peptides were purified by reverse phase HPLC and the major peaks were subjected to N-terminal sequencing. The peptides were derived from a variety of proteins: human serum albumin, human erythroid protein 4.1, 60S ribosomal proteins L31 and L35, VCAM-1, human immunoglobulin lambda chain and cathepsin-S. A peptide corresponding to the sequence of human serum albumin (HSA) residues 106-120 was synthesized and shown to bind to HLA-DR4Dw4 (IC50 = 1.41 microM). We have confirmed and refined current ideas about the structural motif for the binding of peptides to HLA-DR and HLA-DR4Dw4.
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PMID:Purification and characterization of endogenous peptides extracted from HLA-DR isolated from the spleen of a patient with rheumatoid arthritis. 753 63

Lymphocytic beta 1,4-galactosyltransferase (beta 1,4-GalTase, EC 2.4.1.38) activity was measured in B cells using a neoglyco-protein, N-acetylglucosamine-phenylisothiocyanate-bovine serum albumin (GlcNAc-pITC-BSA), as an acceptor substrate in a novel enzyme-linked immunosorbent assay (ELISA)-based method. This assay proved to be much simpler to use than the lengthy and expensive radiochemical assays commonly used, and has the additional advantage that it specifically detects the enzyme mediating transfer via the Gal beta 1,4GlcNAc linkage. A F(ab')2 antibody against GalTase was able to specifically inhibit the reaction. Greater sensitivity for beta 1,4-GalTase activity was obtained using GlcNAc-pITC-BSA as an acceptor substrate rather than ovalbumin. Low levels of beta-galactosidase activity were detectable in lymphocyte cell lysates at acidic pH, although such activity was not detectable at the neutral pH used in the beta 1,4-GalTase activity assay. Using this assay with the GlcNAc-pITC-BSA acceptor, similar beta 1,4-GalTase activities were observed in CD19+ B cells from patients with rheumatoid arthritis (RA) to those seen in normal control individuals.
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PMID:beta 1,4-Galactosyltransferase activity in B cells detected using a simple ELISA-based assay. 757 90

Rheumatoid arthritis is a common cause of chronic disability for which current therapies are of limited value in controlling the disease process and outcome. Our initial approach to understanding the pathogenesis of RA and defining a novel therapeutic target was to investigate the role of cytokines by blocking their action with antibodies on cultured synovial-derived mononuclear cells in vitro. These investigations suggested that neutralization of TNF alpha with antibodies significantly inhibited the generation of other pro-inflammatory cytokines also over-produced, such as, IL-1, GM-CSF, IL-6 and IL-8. The implication that blockade of a single cytokine, TNF alpha might have far-reaching effects on multiple cytokines and thereby exert significant anti-inflammatory and protective effects on cartilage and bone of joints, was tested in arthritic DBA/1 mice immunized with collagen II. Impressive amelioration of joint swelling and joint erosions in this model encouraged clinical trials with a monoclonal anti-TNF alpha antibody. The cA2 chimeric anti-TNF alpha high-affinity antibody was initially tested in an open-label study at a dose of 20 mg/kg on 20 patients, with substantial and universal benefit. Subsequently, a randomized placebo-controlled double-blind trial was performed on 73 patients comparing a single intravenous injection of placebo (0.1% human serum albumin) with two doses of cA2. Using a composite disease activity index, at 4 weeks post infusion, 8% of patients receiving placebo improved compared with 44% receiving 1 mg/kg cA/2 and 79% receiving 10 mg/kg. Between 2 to 4 repeated cycles of cA2 were administered to 7 patients and all patients showed improvement of a similar magnitude with each cycle. These data support our proposition that TNF alpha is implicated in the pathogenesis of RA, and is thus a key therapeutic target. Monoclonal anti-TNF alpha antibodies control disease flares and are candidate agents for longer-term control of RA, although repeated therapy with cA2 is associated with anti-idiotypic responses in 50% of patients and a trend toward shortening of the duration of response. In the DBA/1 arthritic mice, synergy of action of anti-TNF and anti-CD4 is observed together with suppression of an anti-globulin response, indicating one way in which benefit might be augmented in the future.
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PMID:Monoclonal anti-TNF alpha antibody as a probe of pathogenesis and therapy of rheumatoid disease. 759 Aug 14

Inflammatory cytokines have been implicated in the pathogenesis of rheumatoid arthritis (RA), whereas the mechanisms for constitutive production of inflammatory cytokines in affected joints are largely unknown. Recently, integrin-mediated interaction with extracellular matrix (ECM) proteins has been demonstrated to play a role in regulating cytokine production in T cells and monocytes. In this study, we investigated the contribution of the beta 1 integrin-mediated interaction with ECM proteins to the persistent cytokine gene expression in RA synovial fluid mononuclear cells (SFMNC). We examined mRNA expression of 14 cytokines in the SFMNC of three RA patients, which were either fresh or cultured overnight in serum-free medium on ECM-coated plates, by polymerase chain reaction with a panel of oligonucleotide primers specific for each cytokine. The persistent expression of various cytokine mRNA found in fresh SFMNC was maintained after overnight culture in serum-free medium on ECM proteins, especially on laminin (LM), but not on serum albumin. This effect of LM was inhibited by an anti-integrin beta 1 chain (CD29) mAb, as well as by an anti-CD3 mAb, indicating an important role of the beta 1 integrin-mediated interaction with ECM proteins in regulating persistent cytokine gene expression in RA SFMNC, and a key role of T cells in regulating inflammatory monokine production.
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PMID:Beta 1 integrin-mediated interaction with extracellular matrix proteins regulates cytokine gene expression in synovial fluid cells of rheumatoid arthritis patients. 767 13

Human recombinant interleukin-1 receptor antagonist (rhIL-1ra), a 17.2 kd protein is currently in clinical trials for the treatment of rheumatoid arthritis (RA). Skin reactions in some patients with RA prompted investigation of a possible pathogenesis involving nonimmunologically mediated mast cell degranulation. Rats injected intradermally with 20 microliters of rhIL-1ra (100 or 200 mg/ml) or the rhIL-1ra vehicle CSEP (10 mmol/L Na-citrate, 0.5 mmol/L ethylenediaminetetraacetic acid (EDTA), 0.1% polysorbate 80, 140 mmol/L NaCl, pH 6.5) had marked (15x or 10x, respectively) Evans blue dye permeability increases as compared with rats injected with phosphate-buffered saline solution (PBS) or bovine serum albumin (BSA). The permeability changes were reduced or eliminated by subcutaneous or local treatment with the antihistamine diphenhydramine. Histologic evaluation of skin sections from rats injected intradermally with CSEP or rhIL-1ra in CSEP revealed mast cell degranulation and edema, features not seen in sites injected with PBS or BSA in PBS. Components of the vehicle were investigated individually for their capacity to cause the reaction. Na-citrate (10 mmol/L) induced a greater increase in permeability than did EDTA (0.5 mmol/L) or polysorbate 80 (0.1%), and all produced reactions that were significantly greater than those occurring at PBS-injected sites. Evans blue dye permeability increases after subcutaneous injection of 1 ml of rhIL-1ra (100 mg/ml) in CSEP (with and without diphenhydramine) or rhIL-1ra in PBS were evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cutaneous mast cell degranulation in rats receiving injections of recombinant human interleukin-1 receptor antagonist (rhIL-1ra) and/or its vehicle: possible clinical implications. 770 5

The mechanism underlying the chronic and intermittent course of rheumatoid arthritis is not elucidated. In the present study, the role of interleukin 1 (IL-1) was investigated in exacerbations of antigen-induced arthritis in mice. A flare-up of smoldering inflammation (weeks 3 to 4 of antigen-induced arthritis) was inducible by injection of a small amount of methylated bovine serum albumin into the hypersensitive knee joint. Immunohistochemistry showed IL-1 expression in the synovial lining layer and in focal areas of the inflamed synovium during the flare-up. IL-1 was also measured in 1-hour culture supernatant of synovial tissue taken during the flare-up by a bioassay. The expression of both immunoreactive and bioactive IL-1 in the hypersensitive joint peaked around 6 hours after antigen (2 micrograms of methylated bovine serum albumin) injection and declined thereafter. Antigen rechallenge induced an acute joint swelling of the arthritic joint but not in the naive joint of the sensitized mouse, yet synovia of both joints produced IL-1 after antigen injection. Remarkably, a single intravenous injection of rabbit anti-IL-1 alpha and -beta antibodies 1 hour before antigen rechallenge neutralized IL-1 in the joint. Anti-IL-1 treatment significantly reduced the antigen-induced joint swelling (30 to 40%) but did not affect the profound influx of polymorphonuclear cells in the onset of the exacerbation. However, a profound relief of the inflammation (synovitis) was obtained by IL-1 blockade on day 4 of the exacerbation. Chondrocyte proteoglycan synthesis was markedly suppressed in the antigen-challenged naive knee joints suggesting that this was a direct IL-1 effect as the inflammation was insignificant. Anti-IL-1 treatment was able to maintain chondrocyte proteoglycan synthesis in the antigen-rechallenged joint, which was highly suppressed in the control group. Furthermore, the enhanced proteoglycan breakdown in the antigen-rechallenged joints was significantly decreased in the anti-IL-1 group. We concluded that IL-1 is an important mediator in exacerbations of murine arthritis, and amelioration of cartilage pathology was obtained with anti-IL-1 antibody treatment.
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PMID:Role of interleukin 1 in antigen-induced exacerbations of murine arthritis. 785 31

Cell-free synovial fluid from patients with rheumatoid arthritis contains soluble and insoluble IgG-containing immune complexes which activate reactive oxidant production in human neutrophils. In this report we have measured the effects of inhibitors of signal transduction pathways on neutrophil activation by these complexes and also following activation by synthetic soluble and insoluble immune complexes made from human serum albumin (HSA) and anti-(HSA) antibodies. In all aspects studied, the soluble rheumatoid complexes and the soluble synthetic complexes were indistinguishable in the ways in which they activated neutrophils. Activation of reactive oxidant production in response to these soluble complexes was completely inhibited by pertussis toxin (indicating G-protein coupling of receptor occupancy), completely insensitive to staurosporine (indicating that oxidant production did not require protein kinase C activity), only marginally (< 30%) inhibited by butanol (indicating that dependence upon activity of phospholipase D was minimal), and completely inhibited by chloracysine, an inhibitor of phospholipase A2. In contrast, activation of reactive oxidant production in response to the insoluble rheumatoid or insoluble synthetic immune complexes was largely pertussis toxin insensitive, inhibited by > 50% by staurosporine, inhibited by > 50% by butanol, and completely inhibited by chloracysine. These results show that the receptor-mediated signal transduction systems activated by the soluble and insoluble immune complexes are different. Because the soluble complexes activate a transient burst of reactive oxidant secretion from primed neutrophils, the mechanisms regulating either the release or the intracellular production of oxidants within rheumatoid joints are distinct and hence may be pharmacologically modified independently of each other.
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PMID:Stimulation of reactive oxidant production in neutrophils by soluble and insoluble immune complexes occurs via different receptors/signal transduction systems. 800 62


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