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)

Oral tolerance may be defined as a specific reduction in the immune response brought about by feeding an antigen. It has been reviewed by us recently as a possible treatment of rheumatoid arthritis. It has a respectably long history as an experimental phenomenon, in the course of which a variety of modes of action have been proposed. More recently the following mode of action has been proposed: An antigen, for instance foreign type II collagen, passes from the lumen of the gut across multifold-cells (M-cells) lying under Peyer's patches, and thence into antigen-presenting cells within the patches. These cells then activate a local population of T cells which specializes in the secretion of transforming growth factor-beta (TGF beta) and IL-4. Following activation a few of these cells wander out through the lymphatics and blood stream, and thence through tissue, until they again find type II collagen, their recall antigen. What they find in a patient with inflammatory arthritis, it is believed, is self-type II collagen exposed within the inflamed joints, which they recognize via its cross-reaction with the foreign collagen which had originally activated them. The specialized T cells are then stimulated by their recall antigen to secrete TGF beta and IL-4. These inhibitory cytokines suppress the activity of neighboring disease-inducing Th1 cells ("bystander suppression"). The latter cells presumably recognize one or more autoantigens, the nature of which is unknown. It need not be type II collagen, which figures in the whole story only as an organ-specific antigen, which lures the suppressive T cells to the right place.
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PMID:Immunological basis of oral tolerance. 766 Jun 84

Excessive release of kinin (BK) in the synovial fluid can produce oedema, pain and loss of functions due to activation of B1 and B2 kinin receptors. Activation of the kinin forming system could be mediated via injury, trauma, coagulation pathways (Hageman factor and thrombin) and immune complexes. The activated B1 and B2 receptors might cause release of other powerful non-cytokine and cytokine mediators of inflammation, e.g., PGE2, PGI2, LTs, histamine, PAF, IL-1 and TNF, derived mainly from polymorphonuclear leukocytes, macrophages, endothelial cells and synovial tissue. These mediators are capable of inducing bone and cartilage damage, hypertrophic synovitis, vessel proliferation, inflammatory cell migration and, possibly, angiogenesis in pannus formation. These pathological changes, however, are not yet defined in the human model of chronic inflammation. The role of kinins and their interacting inflammatory mediators would soon start to clarify the detailed questions they revealed in clinical and experimental models of chronic inflammatory diseases. Several B1 and B2 receptor antagonists are being synthesized in an attempt to study the molecular functions of kinins in inflammatory processes, such as rheumatoid arthritis, periodontitis, inflammatory diseases of the gut and osteomyelitis. Future development of specific potent and stable B1 and B2 receptor antagonists or combined B1 and B2 antagonists with y-IFN might serve as a pharmacological basis for more effective treatment of joint inflammatory and related diseases.
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PMID:Pathogenic responses of bradykinin system in chronic inflammatory rheumatoid disease. 770 72

Oral tolerance is a long recognized method to induce peripheral immune tolerance. The primary mechanisms by which orally administered antigen induces tolerance are via the generation of active suppression or clonal anergy. Low doses of orally administered antigen favor active suppression whereas higher doses favor clonal anergy. The regulatory cells that mediate active suppression act via the secretion of suppressive cytokines such as TGF beta and IL-4 after being triggered by the oral tolerogen. Furthermore, antigen that stimulates the gut-associated lymphoid tissue preferentially generates a Th2 type response. Because the regulatory cells generated following oral tolerization are triggered in an antigen-specific fashion but suppress in an antigen nonspecific fashion, they mediate "bystander suppression" when they encounter the fed autoantigen at the target organ. Thus it may not be necessary to identify the target autoantigen to suppress an organ-specific autoimmune disease via oral tolerance; it is necessary only to administer orally a protein capable of inducing regulatory cells that secrete suppressive cytokines. Orally administered autoantigens suppress several experimental autoimmune models in a disease- and antigen-specific fashion; the diseases include experimental autoimmune encephalomyelitis (EAE), uveitis, and myasthenia, collagen- and adjuvant-induced arthritis, and diabetes in the NOD mouse. In addition, orally administered alloantigen suppresses alloreactivity and prolongs graft survival. Initial clinical trials of oral tolerance in multiple sclerosis, rheumatoid arthritis, and uveitis have demonstrated positive clinical effects with no apparent toxicity and decreases in T cell autoreactivity.
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PMID:Oral tolerance: immunologic mechanisms and treatment of animal and human organ-specific autoimmune diseases by oral administration of autoantigens. 801 Dec 98

IgA antibodies against Klebsiella pneumoniae were measured by immunofluorescence in 84 Catalan patients with ankylosing spondylitis (AS), 41 patients with non-inflammatory arthropathies (NIA) and 22 patients with rheumatoid arthritis (RA). Patients with AS showed higher levels of anti-klebsiella IgA antibodies (IgA-Kp) than NIA and RA patients (4.7 +/- 1.6 U vs 3.7 +/- 1.5 U and 3.1 +/- 1.4 U respectively, p = 0.001). In AS patients a significant correlation between IgA-Kp and levels of C-reactive protein was observed. Although no clear correlation was found between IgA anti-klebsiella and total serum IgA levels, a significant correlation between IgA anti-klebsiella and serum levels of secretory IgA was detected (r: 0.43, p = 0.003). In conclusion, some patients with AS disclosed raised levels of Klebsiella antibodies in sera and this is related to an increase of secretory IgA level. Analysis about the relationship between response to klebsiella and the presence of gut inflammation in AS patients could be of interest.
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PMID:Serum IgA anti-Klebsiella antibodies in ankylosing spondylitis patients from Catalonia. 801 81

Suppressor T cells in the mucosa of the gut are activated by absorbed antigen in order to avoid a systemic immune response to this antigen. This long known phenomenon of oral tolerance is now used in the treatment of rheumatoid arthritis with oral collagen type II which is the most important protein of cartilage. Although the role of collagen II in initiating and maintaining the immune response in the joint is not clear, these suppressor CD8+T cells can be stimulated in a trigger-specific and effector-nonspecific way by contact with collagen II in the joint. It is assumed that a local immunosuppression then takes place through the secretion of inhibitory cytokines, mainly TGF beta. Clinical studies in the treatment of rheumatoid arthritis are presently being conducted in Boston and Berlin.
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PMID:[Therapy with oral type II collagen as a new possibility of selective immunosuppression in therapy of rheumatoid arthritis]. 802 85

Sulphasalazine has been used world wide for the treatment of inflammatory bowel diseases for over 40 years. Since the late seventies, sulphasalazine has in addition, been shown to have positive effects in rheumatic diseases e.g. rheumatoid arthritis and spondylarthropathy. Whatever its mechanism of action, the high concentration of sulphasalazine in the gut might explain its beneficial effects on the articular symptoms. Sulphasalazine can be considered as a Disease Modifying Antirheumatic Drug in rheumatoid arthritis and, probably, in spondylarthropathy.
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PMID:Sulphasalazine in rheumatic diseases. 810 62

We have analyzed the V-gene usage in gamma delta T cells of the human gut and joint by using a new mAb (B18) specific for V gamma 8 of human TCR-gamma delta+ T cells. The B18+ population constituted a minor subset of the gamma delta T cells in peripheral blood (PB) of healthy persons (6 +/- 5%) and only 1 of 35 gamma delta T cell clones analyzed was positive. In contrast, the B18+ subset was a dominant gamma delta T cell population among intraepithelial lymphocytes (IEL) derived from the human intestine (74 +/- 29, p < 0.002), and two of three IEL clones from patients with coeliac disease were B18+. Interestingly, a higher proportion of B18+ gamma delta T cells was found in the synovial fluid of patients with rheumatoid arthritis (RA) (21 +/- 18%, 0.02 < p < 0.05) compared with normal PB. Furthermore, the B18+ subset was more frequent among IL-2-expanded gamma delta T cells (42 +/- 20%) derived from synovial tissue than among IL-2-expanded cells derived from synovial fluid (p < 0.002) and PB from RA patients (p < 0.02) as well as normal PB (p < 0.002). The V-gene usage of 13 gamma delta T cell clones from the synovial fluid of arthritic patients was analyzed. All B18+ clones (n = 7) expressed mRNA for V gamma 8 together with mRNA for V delta 1 (n = 5) or mRNA for V delta 3 (n = 2). None of the B18- clones expressed V gamma 8 (n = 6). We conclude that the gamma delta T cell that expresses V gamma 8, together with mainly V delta 1, is a major gamma delta T cell subset among the IEL of the gut and a highly frequent subset in the synovial tissue of patients with RA. This subset may correspond to the mouse V gamma 7+ IEL, which has a high degree of amino acid sequence homology with the human V gamma 8 protein.
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PMID:High expression of V gamma 8 is a shared feature of human gamma delta T cells in the epithelium of the gut and in the inflamed synovial tissue. 820 27

We report the emergence of polyclonal expansion of gut lymphocyte associated tissues producing IgA in a patient with rheumatoid arthritis associated with a high serum IgA concentration. The role of IgA in rheumatoid arthritis is reviewed.
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PMID:Expansion of gut associated immunoglobulin A secreting lymphocytes in rheumatoid arthritis correlates with high levels of serum IgA. 835 90

Pulse steroid therapy is utilised in the treatment of vasculitis and active rheumatoid arthritis. Decreased entry of lymphocytes to sites of cell-mediated immune reactions is well recognised, though the mechanism is not fully understood. It may involve adhesion to endothelium. We have therefore measured the effect of methylprednisolone on lymphocyte adhesion to porcine lamina propria endothelium. A marked decrease in adhesion was found after incubating cells at 4 degrees C or at room temperature, with a clear dose response effect, from 0.46mM to 6.3mM. We have previously demonstrated binding of rheumatoid synovial fluid mononuclear cells to lamina propria endothelium. It is suggested that the ameliorating effect of steroid pulsing may be mediated by down-regulating adhesin expression of a gut-seeking population of cells.
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PMID:Effect of corticosteroid on lymphocyte adhesion. 852 99

By a study of the adhesion of rheumatoid mononuclear cells, we have sought to clarify the homing properties and origins of cells likely to be involved in the pathogenesis of this disease. The adhesion of mononuclear cells from patients with rheumatoid arthritis (RA) was enumerated by an in vitro adherence assay using frozen sections of endothelium-containing gut lamina propria (EGLP) from porcine small intestine. Preliminary studies verified the involvement of known adhesion molecules by inhibition assays using monoclonal antibodies Meca-367, Mel-14 and Hermes-3. Twenty-five paired samples of peripheral blood (PB) and synovial fluid (SF) were studied, plus six from synovial membrane (SM) and eight from patients with other diseases. There was a significantly greater degree of adherence to EGLP by SF cells than PB (mean adherence 266 +/- 22 cells/mm(2), compared to 136 +/- 13 cells/mm(2), respectively, the majority of which were CD8+ cells; P=0.02, Mann-Whitney U-test for 25 paired samples). The results of the monoclonal antibody inhibition assays were in keeping with the involvement of homing receptors to gut endothelium in our assay system. Synovial fluid lymphocytes from RA patients exhibited adhesion properties more in keeping with lymphocytes of mucosal than of lymph node origin. Synovial membrance lymphocytes, by contrast, showed poor adherence to endothelium-containing lamina propria. The gut, as an immune lymphoid organ, may thus play a contributory role in this disease, possibly through the pathological seeding of cells into the synovial space.
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PMID:Adhesion of rheumatoid lymphocytes to mucosal endothelium: the gut revisited. 862 Feb 95


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