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)

Lymphocytes from the synovial fluid of eight out of eight rheumatoid arthritis (RA) patients had elevated very late activation antigen-1 (VLA-1) expression (10-36% positive cells), whereas peripheral blood lymphocytes (PBL) from RA patients and healthy controls had low VLA-1 expression (0-6% positive cells). During 1-2 wk of in vitro culture, VLA-1 increased on synovial fluid cells but remained low on PBL. In comparison, the interleukin 2 receptor (IL-2 R) was less prominent than VLA-1 on fresh synovial fluid cells, did not increase on cultured synovial fluid T cells, but did increase greatly on cultured PBL. The mitogen PHA reversed or prevented the appearance of VLA-1+, IL-2 R- synovial fluid cells during in vitro culture, thus giving IL-2 R+, VLA-1- cells. These results emphasize that VLA-1+ SF cells are different from resting cells or IL-2 R+ activated PBL T cells, and VLA-1 on synovial fluid T cells may be incompatible with mitogen stimulation. In addition, the VLA-2 heterodimer (165,000/130,000 relative molecular mass [Mr]) was regulated opposite to the VLA-1 heterodimer (130,000/210,000 Mr) on synovial lymphocytes, and thus the VLA-1/VLA-2 ratio is another indicator of the stage of T cell activation.
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PMID:Very late activation antigens on rheumatoid synovial fluid T lymphocytes. Association with stages of T cell activation. 301 43

Rheumatoid Arthritis (RA) is characterised by the presence of activated lymphocytes in the synovial compartment, which are classically considered to be of particular importance to the pathogenesis of the disease. We have shown that activated lymphocytes are also found in the rheumatoid lymph nodes and peripheral blood, and that their proportions are increased in early or active disease. Double-labelling experiments showed that T cell subsets within the activated circulating lymphocytes resemble closely those found in the synovium, and suggested an important role for circulating activated lymphoid populations in the pathogenesis of RA. In vitro studies indicate that although rheumatoid lymphocytes express activation markers, they are functionally deficient. This is well established in the case of synovial lymphocytes. We have demonstrated that functional defects are also present in circulating rheumatoid lymphocytes, which show a decreased autologous mixed leucocyte response (AMLR), corrected partially by the addition of exogenous IL-2. They also proliferate poorly in response to PHA and produce significantly less IL-2 than normal controls. This is more marked in patients with active or complicated RA. These defects cannot be explained by a lack of CD4+2H4+ cells which we have shown to be the major IL-2-producing circulating lymphocyte subpopulation. These findings suggest an intrinsic-functional rather than a numerical deficiency of the IL-2 producing T cells in RA. In recent experiments we have shown that non-lymphoid populations, such as activated phagocytic cells, are also involved in the deficient rheumatoid T cell function, partly via the production of prostaglandins and reactive oxygen intermediates. We and others have demonstrated that the latter may significantly and selectively affect lymphocyte viability and function. These findings may explain the differences in the functional capacity of lymphocytes frequently observed between cells derived from different sites or at different stages of the disease. We suggest that it is not lymphocyte activation as such, but its defective nature, that is of pathogenetical importance in RA. Furthermore, the T cell system should not be viewed and studied in isolation in this disease, but its interactions with inflammatory cells should be taken into account.
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PMID:The T cell system in rheumatoid arthritis: activated or defective? 307 73

Cyclosporin A (Sandimmun) has gained wide acceptance by most transplant physicians as the immunosuppressant of choice for preventing rejection of solid organ grafts and graft-versus-host disease. The drug has a specific effect on T-lymphocytes in which it seems to prevent the transcription of genes for several lymphokines. The reduction in IL-2 prevents the clonal expansion of T-lymphocytes and their differentiation into effector T-cells. The reduction in IFN-tau interrupts the feedback mechanism between T-cells and macrophages and the aberrant expression of MHC class II molecules. Through these mechanisms Sandimmun exerts an immunosuppressive and anti-inflammatory effect. Considerable evidence has accumulated to suggest that rheumatoid arthritis (RA) is an auto-immune disease. Activated T-lymphocytes interrelate with macrophages, other inflammatory cells and effector cells in joint tissue, leading to symptoms of inflammation accompanied by joint destruction. Immunosuppressive treatment is already well established in this disease and several trials have already taken place using Sandimmun. A total of 224 patients with RA refractory to conventional disease-modifying drugs have participated in 11 published clinical studies. A review of these studies concludes that Sandimmun is efficacious in controlling inflammatory and functional symptoms, although this improvement is no generally accompanied by reductions in ESR and rheumatoid factor. The frequency of adverse events is comparable to that of other treatments but nephropathy remains the principal factor limiting the use of Sandimmun. Recent evidence suggests that with a strict dosage strategy and good monitoring this problem is controllable and reversible. Further studies are under way to confirm these claims.
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PMID:Sandimmun (cyclosporin A): mode of action and clinical results in rheumatoid arthritis. 307 82

Synovial fluid lymphocytes (SFL) and peripheral blood lymphocytes (PBL) from patients with rheumatoid arthritis (RA) and reactive oligoarthritis were investigated for activated T cells (Ia+SIg-), IL-2 receptor bearing cells (Tac+) and IL-2 production in vivo and in vitro. In contrast to negative results with blood, the synovial fluid of the arthritic joints contains considerable amounts of IL-2 activity (median: 11.8 mu/ml), elevated proportions of Ia+SIg- activated T cells (median: 12.5%) and of IL-2 receptor bearing cells (median: 2.5%). In vitro, after stimulation with several Concanavalin A (Con A) doses, SFL develop proportions of IL-2 receptor cells comparable to PBL. Furthermore, they produce higher values of IL-2 activity than comparable PBL cultures. The proportions of Ia+SIg- activated T cells increase only moderately after Con A stimulation compared to in vivo data, indicating different activated T cell subsets in the synovial fluid (Ia+SIg-, Tac+). The findings are discussed as an expression of an acute hyperactivation of lymphocytes in an inflamed joint.
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PMID:Evidence for enhanced interleukin 2 (IL-2) secretion and IL-2 receptor presentation by synovial fluid lymphocytes in rheumatoid arthritis. 308 51

Gold salts, auranofin (AF), aurothiomalate (ATM) and aurothioglucose (ATG) displayed immunosuppressive action in a series of in vitro assays which mimic the cell-cell interactions thought to occur in rheumatoid arthritis. The gold salts inhibited phytohaemagglutinin (PHA)-induced thymidine incorporation and gamma-IF production by peripheral blood mononuclear cells, as well as IL-2-induced proliferation of PHA-blasts. The separate addition of IL-2 and gamma-IF partly reversed the anti-proliferative effects of ATM and ATG; however, the addition of IL-1 had no effect. ATM and ATG inhibited PHA-stimulated IL-1 production by mononuclear cells but not spontaneous or LPS-induced IL-1 production by adherent monocytes. It was concluded that ATM and ATG inhibited lymphocyte function and lymphocyte-amplification of macrophage function. The anti-proliferative effects of AF were partly reversed by IL-2 but not by gamma-IF or IL-1. AF inhibited PHA-stimulated IL-1 production by mononuclear cells as well as spontaneous and LPS-induced production by adherent cells. It appeared that AF inhibited lymphocyte and macrophage function directly. AF also displayed potential anti-inflammatory activity in that it inhibited PGE2 and collagenase production by proteolytically dispersed rheumatoid synovial cells.
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PMID:Unique properties of auranofin as a potential anti-rheumatic drug. 309 56

The analysis of T lymphocytes infiltrating tissues afflicted by autoimmune diseases may provide major clues towards understanding the pathogenesis of such diseases. Currently the best approach to studying heterogeneous populations such as T lymphocytes involves long-term culture and cloning. In order to grow and clone T lymphocytes, regular restimulation with the specific antigen is essential, otherwise growth will stop and/or specificity may be lost. In autoimmune diseases the antigens involved in triggering the immunological reaction of T cells are usually unknown. Therefore an alternative way of stimulating T lymphocytes without loss of specificity is clearly needed. Here we describe the cloning and expansion of antigen-specific T cell clones from the blood of a healthy donor to sizeable numbers of cells (greater than 10(8)) by means of anti-CD3 monoclonal antibody and recombinant IL-2. The results obtained showed that this approach can be used to clone and 'expand' T lymphocytes that retain antigen specificity over a prolonged period, in this case over 10 weeks. This technique has been used to clone and expand T lymphocytes infiltrating the affected tissues in a variety of autoimmune disorders such as Hashimoto's thyroiditis, Graves' disease, and rheumatoid arthritis, and is an efficient method of propagating T cells, by mimicking the antigenic stimulus.
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PMID:Efficient propagation and cloning of human T cells in the absence of antigen by means of OKT3, interleukin 2, and antigen-presenting cells. 325 81

The synovial fluid of patients with rheumatoid arthritis (RA) contains a biologically active factor which has the ability to replace T cells for the induction of antibody secretion by human blood lymphoid cells stimulated by pokeweed mitogen (PWM) in vitro. This factor, which will be referred to as RA-SF (synovial fluid), also has the capacity to act as a B cell-stimulatory factor of mouse splenic lymphocytes in the presence of lipopolysaccharide (LPS). Using a test system developed for the definition of interleukin 4 (IL-4), which is a B cell-stimulating lymphokine which preferentially activates the synthesis of selected Ig classes in mouse lymphoid cells, we have shown that RA-SF has properties similar to IL-4 in that it induces differentiation of antibody secretion in the LPS-pretreated mouse cell, but unlike IL-4, which gives IgG1 and IgE, it selectively induces IgG2b synthesis. The present study demonstrates that RA-SF has a biological activity that is reminiscent of other B cell-stimulating mouse lymphokines, but it is biologically distinct from IL-2, IL-4, and IL-5. Recent data also indicate that it is distinct from gamma interferon (IFN-gamma). Therefore, we conclude that the biological activity of RA-SF has properties in common with a T-cell replacing (TRF) and B-cell differentiation factor (BCDF) and probably represents yet another biological activity which so far lacks an experimental counterpart. The relevance of this factor for autoantibody synthesis is discussed.
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PMID:Biological characterization of T cell-replacing factor in the synovial fluid of rheumatoid arthritis patients. 326 Jun 84

Since evidence for the presence of IL-2 activity in rheumatoid synovial fluid is conflicting, we have assayed IL-2 activity in synovial fluid from patients with rheumatoid arthritis (RA) and other articular diseases (OAD). Using the IL-2-dependent murine T cell line CTLL, IL-2 activity was not demonstrable in synovial fluid tested at concentrations ranging from 50% to 0.02%. There was an inhibitory effect on IL-2 activity in the bioassay of synovial fluid from 16 of the 22 patients with RA and 15 of the 16 with OAD. This inhibitory activity was heat-labile, precipitable by ammonium sulphate, reversible with excess IL-2 and was not significantly altered by preincubation of synovial fluid with CTLL. The mean inhibitory activity of synovial fluid from patients with RA was significantly reduced in comparison with that of synovial fluid from patients with OAD. Sera also had an inhibitory effect on IL-2 activity; however sera from patients with RA were less inhibitory than control sera but were more inhibitory than sera from patients with systemic lupus erythematosus. The deficiency in synovial fluid of an inhibitor of IL-2 activity may be relevant to the pathogenesis of RA.
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PMID:Interleukin 2 inhibitor in synovial fluid. 326 Aug 39

Peripheral blood mononuclear cells (PBM) from 11 patients with rheumatoid arthritis (RA) stimulated with 0.13 and 0.25 microgram/ml phytohaemagglutinin (PHA) for 3 days showed a depressed expression of interleukin 2 receptor (IL-2R) when compared with 14 normal controls (P less than 0.01). At these two doses of PHA a depressed lymphocyte proliferative response was also observed (P less than 0.01). However the kinetics of the response of the RA group differed from those of the control group. Whereas by day 6 IL-2R expression and lymphocyte proliferation in the control group was decreased compared with day 3, responses of the RA cells were increased. Following stimulation with the higher dose of PHA (1 microgram/ml) the kinetics of lymphocyte proliferation and IL-2R expression were equivalent in control and RA cultures. These results demonstrate that the impaired IL-2R expression and lymphocyte proliferation observed with sub-optimally stimulated PBM from RA patients is spontaneously reversed during prolonged culture and is consistent with the hypothesis that there is a lack of available IL-2 in the early stages of culture.
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PMID:Spontaneous recovery of the decreased expression in vitro of interleukin 2 receptors in rheumatoid arthritis. 326 68

An ELISA was used to measure soluble IL-2R (sIL-2R) in the sera and synovial fluids of patients with rheumatic diseases. Patients with rheumatoid arthritis had raised levels of sIL-2R both in their sera and in their synovial fluid compared to patients with osteoarthritis and age-matched healthy controls. Mononuclear cells from the synovial fluid of rheumatoid arthritis patients were found to produce spontaneously high levels of sIL-2R which eluted at approximately m.w. 40,000 on gel filtration. In contrast, autologous peripheral blood cells only produced comparable levels upon stimulation with mitogenic lectin. Sequential studies indicated that serum sIL-2R levels were highly correlated with disease activity, indicating that measurement of sIL-2R may be a useful clinical marker in the future. Within the joint, synovial fluid sIL-2R levels correlated significantly with immunoreactive IL-1 beta levels, providing evidence for a role of IL-1 in immune activation in the synovium. In synovial fluids, sIL-2R level also correlated with functional inhibition of IL-2-driven responses in vitro. Furthermore, sIL-2R immunoreactivity in synovial fluid eluted at m.w. 100,000 coeluting with IL-2-inhibitory activity and consistent with a role for sIL-2R in down-regulation of IL-2 responses. The abnormal m.w. may be accounted for by complex formation in the synovial fluid. Given the ability of sIL-2R to bind IL-2, the presence of sIL-2R within the joint may contribute to the well documented "IL-2 defect" seen in rheumatoid arthritis.
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PMID:Soluble IL-2 receptor in rheumatoid arthritis. Correlation with disease activity, IL-1 and IL-2 inhibition. 326 65


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