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Biomedical subjects

E C Keystone

Publications and source records attributed to E C Keystone.

At least 19 recordsLinked to original sources

HLA antigens in North American patients with Takayasu arteritis.

OBJECTIVE: To determine the frequency of HLA class I and II antigens in Caucasian North American patients with Takayasu arteritis (TA). METHODS: Seventy-three class I antigens and 13 class II antigens were examined in 21 Caucasian North American patients with TA, and their frequencies were compared with findings in 243 healthy, untreated controls. HLA typing was performed by microlymphocytotoxicity assay. RESULTS: We found no statistically significant positive association of TA with DR2, DR4, DQw3, or any of the other class I or class II antigens studied. A negative association between TA and DR1 was noted. There was no significant association between any of the HLA antigens and the severity of the disease or the presence of complications. CONCLUSION: The negative association between TA and the DR1 antigen suggests that this antigen may be protective against the development of the disease.

Adolescent

Impaired generation of high-affinity interleukin-2 receptors in the autologous mixed lymphocyte reaction in rheumatoid arthritis.

We examined the expression of high-affinity interleukin (IL)-2 receptors (IL-2R) as well as Tac and HLA-DR antigens on peripheral blood (PB) T cells from 11 rheumatoid arthritis (RA) patients and 8 healthy controls induced in the autologous mixed lymphocyte reaction (AMLR). The proportion of HLA-DR- and Tac-bearing T cells and expression of these activation antigens were higher in patients relative to controls (P less than 0.01) in freshly isolated unstimulated PB mononuclear cells. AMLR stimulation of RA T cells failed to induce an increase in the proportion of HLA-DR and Tac-bearing T cells which was observed in health controls. After AMLR stimulation the number of high-affinity IL-2R were significantly lower in RA patients compared with controls (P less than 0.01). The number of high-affinity IL-2R on patient T cells correlated strongly with AMLR reactivity as measured by [3H]thymidine incorporation (r = 0.821, P = 0.002). The results suggest that the AMLR defect in RA may result from impaired generation of high-affinity IL-2R.

Adult

Infections that cause vasculitis.

An infectious cause has long been suspected for most forms of vasculitis. In most cases vascular damage has been ascribed to immune-mediated mechanisms rather than direct microbial toxicity. Evidence cited in this review provides further support for a causal role of infection in the vasculitides by strengthening the link between group A streptococci and hepatitis B virus with polyarteritis nodosa and Kawasaki syndrome. It is anticipated that the application of new molecular technology will provide definitive evidence for the role of infection in the etiopathogenesis of the vasculitides.

Antibodies, Antineutrophil Cytoplasmic

Elevation of a gamma delta T cell subset in peripheral blood and synovial fluid of patients with rheumatoid arthritis.

We examined the levels of TcR delta 1+ T cells (total gamma delta T cell) and delta TCS1+ (gamma delta T cell subset) T cells in the peripheral blood (PB) and synovial fluid (SF) of 16 patients with rheumatoid arthritis (RA) and compared them to the levels in PB of patients with Felty's syndrome (FS) and 21 healthy control subjects (NML). Synovial fluid from eight patients with seronegative spondyloarthropathies (SSA) was also examined. The results demonstrated elevated levels of the delta TCS1+ subset in the PB of RA and FS patients relative to NML (P less than 0.05). No such differences were observed in the levels of PB TcR delta 1+ T cells. The results did not appear to reflect a non-specific inflammatory response since delta TCS1 T cells were elevated in the SF of RA patients relative to SSA SF and NML PB. delta TCS1 T cells in SSA PB and SSA SF were comparable to NML PB. TcR delta 1+ T cells levels in RA SF were higher than SSA SF levels but were comparable to those of NML PB. Taken together, the results support a pathogenic role for delta TCS1+ T cells in RA.

Antibodies, Monoclonal

Giant cell arteritis presenting as limb claudication. Report and review of the literature.

Upper limb claudication and pulselessness is an uncommon presentation of giant cell arteritis (GCA), often resulting in delayed diagnosis. We describe such a case diagnosed by angiography, in which a temporal artery biopsy showed classic GCA, despite the absence of local signs or symptoms. A review of 26 similar cases revealed that in 81% of patients where the only manifestation of GCA was upper limb findings, temporal artery biopsy yielded positive findings. Steroid therapy clinically improved 24/26 patients. These findings suggest that a consideration of temporal artery biopsy early in the investigation will hasten diagnosis and appropriate therapy.

Aged

Erythema nodosum and non-Hodgkin's lymphoma.

We describe a case of erythema nodosum associated with non-Hodgkin's lymphoma. The course and resolution of the erythema nodosum correlated most closely with a breakdown and release of new antigen at the start of a new regimen of chemotherapy.

Adult

Serial levels of soluble interleukin 2 receptor in the peripheral blood of patients with rheumatoid arthritis: correlations with disease activity.

We serially assayed soluble interleukin 2 receptor (sIL-2R) levels in the peripheral blood (PB) of 22 patients with rheumatoid arthritis (RA) followed for a period of 12 months, and correlated these levels with disease activity. We examined the relationship between the direction in which each of the disease measures changed between assessments and the direction of change in sequential sIL-2R levels. In 22 of the 25 (88%) instances where there was a 30% change in the active joint count between sequential assessments, the direction of change of the PB sIL-2R level was found to be in parallel (chi 2 = 11.7, p less than 0.008). Our results suggest that serial sIL-2R levels are a useful means of confirming clinically significant changes in disease activity in patients with RA, irrespective of therapy.

Anti-Inflammatory Agents

Impaired late suppression of Epstein-Barr virus (EBV)-induced immunoglobulin synthesis: a common feature of autoimmune disease.

We examined regulation of Epstein-Barr virus-induced plaque-forming cell generation in peripheral blood mononuclear cells from several autoimmune and seronegative diseases and correlated these results with Epstein-Barr virus-induced proliferation. We confirmed the defective regulation of Epstein-Barr virus-induced plaque-forming cells in peripheral blood mononuclear cells of patients with rheumatoid arthritis and scleroderma. Peripheral blood mononuclear cells from patients with seronegative arthropathies and chronic infective inflammation (cystic fibrosis) had normal regulation of Epstein-Barr virus-induced plaque-forming cells. Peripheral blood mononuclear cells from rheumatoid arthritis had excessive plaque-forming cell generation in the face of a normally regulated decrease in Epstein-Barr virus-induced proliferation. In contrast, peripheral blood mononuclear cells from scleroderma had defective suppression of both Epstein-Barr virus-induced proliferation and plaque-forming cell generation. Thus, impaired regulation of Epstein-Barr virus-induced plaque-forming cell generation is a common feature of autoimmune disease and demonstrates some specificity for these disorders.

Adult

Elevated soluble interleukin-2 receptor levels in the sera and synovial fluids of patients with rheumatoid arthritis.

In a previous study, we used an enzyme-linked immunosorbent assay to measure soluble human interleukin-2 receptors (IL-2R), and found that when activated lymphocytes produce cell-associated IL-2R, they also release a soluble form of IL-2R into culture supernatants in vitro. Soluble IL-2R have also been detected circulating in vivo at low levels in the serum of healthy individuals, and at abnormal levels in a variety of diseases, particularly those where immune dysfunction is thought to play an important role. We therefore evaluated serum IL-2R levels in 77 patients with rheumatoid arthritis (RA), and compared them with levels in 46 age-matched healthy controls. Nineteen additional RA patients with concurrently obtained sera and synovial fluid (SF) samples were compared with 14 patients with osteoarthritis of the knee or hip. The serum IL-2R levels were significantly elevated in RA patients, compared with the control groups (P less than 0.0001). Serum IL-2R levels in the RA patients did not correlate with disease activity as determined by a variety of clinical and laboratory parameters. RA SF IL-2R levels were significantly higher than corresponding RA serum IL-2R levels (P = 0.0001). No such difference was noted in the osteoarthritis group, where serum and SF IL-2R levels were comparable with serum levels in healthy controls. These findings support the hypothesis that in vivo lymphocyte activation plays an important role in RA; moreover, soluble IL-2R measurement in serum and SF may be a very useful way to identify patients at risk for, or manifesting, a chronic immune-mediated inflammatory arthropathy.

Anti-Inflammatory Agents, Non-Steroidal

Structure of T cell antigen receptor beta chain in synovial fluid cells from patients with rheumatoid arthritis.

We attempted to identify a clonal proliferation of T cells from synovial fluid samples from patients with rheumatoid arthritis, using techniques of restriction fragment length polymorphism. We used probes for the beta chain of the T cell receptor to analyze restriction fragments prepared from the genomic DNA of synovial fluid mononuclear cells from 10 patients and synovial fluid T cell preparations from 5 additional patients. The results demonstrated unarranged (germline) T cell receptor gene fragments of DNA in all cell preparations, indicating the lack of clonality of rheumatoid arthritis synovial fluid T cells.

Arthritis, Rheumatoid

Reactivity of T-cells from patients with rheumatoid arthritis to anti-CD3 antibody.

The ability of an anti-CD3 monoclonal antibody (OKT3) to induce proliferation was examined in peripheral blood mononuclear cells (PBM) from 30 patients with rheumatoid arthritis (RA). Controls consisted of 10 patients with osteoarthritis, 12 patients with psoriatic arthritis, and 12 healthy subjects. The results revealed enhanced PBM reactivity in patients with active RA relative to inactive RA patients and all control groups. PBM of patients with mild/moderate clinical disease activity exhibited augmented anti-CD3 reactivity while those with severe disease demonstrated impaired reactivity. Enhanced reactivity was also observed in the active RA group using another anti-CD3 monoclonal antibody (Leu-4). Differences in anti-CD3 dose-response or time kinetics could not account for the results. Studies of enriched T-cell preparations revealed a markedly enhanced anti-CD3 reactivity of RA T-cells relative to normal control T-cells. Monocyte/T-cell mixing experiments revealed no enhanced reactivity of RA monocytes in the anti-CD3 response. RA T-cell preparations depleted of monocytes by limiting dilution reacted significantly more to anti-CD3 in the presence of IL-2 relative to controls. The enhanced reactivity could be accounted for in part by hyperreactivity of the OKT8-bearing subpopulation of T-cells.

Antibodies, Monoclonal

Serum phospholipase A2 correlates with disease activity in rheumatoid arthritis.

We previously demonstrated a marked elevation of the proinflammatory enzyme phospholipase A2 (PLA2) in all synovial fluids and some sera of patients with rheumatoid arthritis (RA). Since PLA2 was found to induce inflammatory changes in the skin and joints of experimental animals, we tested whether the serum level of PLA2 correlates with the clinical activity of RA. In the group of 51 patients with classical or definite RA, 13 (25%) had high serum levels of PLA2 (over 2 standard deviations above the normal mean). Comparison of clinical disease activity in patients with high levels of PLA2 with those with normal PLA2 levels showed that patients with high PLA2 levels had a significantly higher joint count, more swollen joints, much higher Landsbury index, lower functional class, lower hemoglobin, lymphopenia and higher erythrocyte sedimentation rate (ESR). To more accurately assess the relationship between the PLA2 level and disease activity in RA, we formulated 2 indices. Clinical index consisted of the Landsbury index, number of swollen joints and duration of morning stiffness. Laboratory index consisted of hemoglobin, absolute number of peripheral blood lymphocytes, platelet count and ESR. Our results showed that both indices correlated strongly with PLA2 activity (p less than 0.0001). The results support the hypothesis that PLA2 plays a pathogenetic role in RA and suggest that serum PLA2 levels may serve as an additional measure of disease activity.

Adult

HLA-DR4 in giant cell arteritis: association with polymyalgia rheumatica syndrome.

Forty-three patients with well-documented giant cell arteritis (GCA) were studied clinically and with HLA typing. All patients were over age 40. Twenty-two of the patients had coexistent polymyalgia rheumatica (PMR). No association with class I HLA antigens was detected. When compared with HLA findings in 243 healthy controls, HLA-DR4 was increased in patients with GCA and PMR, but not in patients with GCA alone. Pooled analysis of data from 4 published papers confirmed the association of DR4 with GCA and PMR (P much less than 0.00001). Patients with PMR but negative findings of temporal artery biopsies also showed an increased frequency of HLA-DR4, but this did not reach statistical significance, probably because of the small number of subjects. It is likely that the increased frequency of DR4 in GCA patients is related to its association with PMR.

Adult

Significance of anticentromere antibody in idiopathic Raynaud's syndrome.

Fifty-eight patients with Raynaud's syndrome who had no evidence of definite underlying connective tissue disease had serum analyzed for the presence of anticentromere antibody using indirect immunofluorescence techniques on HEp-2 cell lines. Eighteen patients (31 percent) were anticentromere antibody-positive. The anticentromere antibody-positive group demonstrated significantly more frequent digital telangiectases, digital edema, elevated levels of immunoglobulins, and low C4 values. Photoplethysmography revealed significantly diminished blood flow in the anticentromere antibody-positive group. Capillary microscopy revealed significantly increased avascularity and number of dilated loops in the anticentromere antibody-positive group. Giant loops were seen exclusively in the anticentromere antibody-positive group. The clinical findings in the anticentromere antibody-positive group are suggestive of a transition to a connective tissue disease with features of the CREST syndrome.

Adult