Plasma and synovial fluid interleukin-1, interleukin-6 and substance P concentrations in rheumatoid arthritis patients: Effect of the nonsteroidal anti inflammatory drugs indomethacin,diclofenac and naproxen

We performed an open, between patients, placebo controlled study in order to evaluate the effect of the treatment with the non steroidal anti inflammatory drugs indomethacin, diclofenac and naproxen on the concentrations of the cytokines IL-1 and IL-6 and of the neuropeptide substance P in plasma and synovial fluid of 24 rheumatoid arthritis patients. All patients had high synovial fluid cytokine and substance P levels, and high plasma cytokine levels at the beginning of the study. The treatment with the non steroidal anti inflammatory drugs significantly decreased both plasma and synovial fluid IL-6 and synovial fluid substance P in comparison to placebo, but did not affect IL-1 concentrations. This effect can participate in the therapeutic effect of non steroidal anti inflammatory drugs in rheumatoid arthritis.     

Correlation of anti-cytoskeleton antibody activities in synovial fluid with interleukin-6 in patients with osteoarthritis and inflammatory joint disease

Summary Synovial fluids and sera from patients with rheumatoid arthritis, psoriatic arthritis, yersinia arthritis, Behçet's syndrome, Crohn's disease, and osteoarthritis were tested for antinuclear antibodies and antibodies to five cytoskeletal components in sensitive enzyme-linked immunosorbent assay (ELISA) systems and for IL-6 concentrations in a proliferation assay (IL-6 dependent hybridoma cell line B13.29, subclone B9). Statistically significant correlations between antibody activities and IL-6 levels were found for vimentin antibodies (r= 0.56; p<0.05) and actin antibodies (r= 0.44;p<0.05). In patients with chronic and active disease like rheumatoid arthritis and psoriatic arthritis, optical densities measured by vimentin- and actin-ELISA were significantly different from those measured in patients with osteoarthritis. To date only a few reports exist concerning the incidence of antibodies in synovial fluids. We have shown to our knowledge for the first time that IL-6 seems to induce synovial fluid antibody activities restricted to cytoskeletal components of synoviocytes (i.e., vimentin and actin). Synovial fluid antibody activities against vimentin and actin appear to be markers of activity in patients with inflammatory joint disease.Abbreviations ELISA enzyme-linked immunosorbent assay - ANA antinuclear antibodies - ACA antibodies against cytoplasmic components - RA rheumatoid arthritis - OA osteoarthritis - SF synovial fluid - RF rheumatoid factors - FCS fetal calf serum - IFT immunofluorescence microscopy - PBS phosphate buffered saline - BSA bovine serum albumin - OD optical density - SLE systemic lupus erythematosus - IL-6 interleukin-6 - HGF hybridoma growth factor - BSF-2 B-cell-stimulatory factor - DMEM Dulbecco's modified Eagles Medium     

Terminal complement complexes and C1/C1 inhibitor complexes in rheumatoid arthritis and other arthritic conditions.

Terminal complement complex (TCC) and C1r-C1s-C1 inhibitor complex (C1/C1 INH) concentrations were measured in plasma and synovial fluid from patients with arthritis and related to other measures of disease activity. Both TCC and C1/C1 INH concentrations were significantly increased in patients with rheumatoid arthritis (RA) compared with patients with osteoarthritis (plasma and synovial fluid, P less than 0.05) and normal subjects (plasma only, P less than 0.001). In the patients with RA, there was no correlation between plasma or synovial fluid TCC concentrations and IgM rheumatoid factor, immune complex or C1/C1 INH levels. However, in 10 patients with seronegative RA, C1/C1 INH and immune complex levels correlated significantly in synovial fluid (r = 0.69, P less than 0.05) although not in plasma (r = 0.52). Plasma and synovial fluid TCC and C1/C1 INH concentrations did not differ in rheumatoid patients with severe compared with mild joint disease (categorized by the Ritchie score). These results confirm a role for complement activation in RA but suggest that several mechanisms are involved in its pathogenesis.     

Interleukin-6 in synovial fluid from patients with arthritis

Synovial fluid and serum from patients with rheumatoid arthritis, other inflammatory arthritides, and traumatic arthritis were assayed for the presence of interleukin-6 (IL-6) by means of an IL-6-dependent mouse hybridoma cell line. The cytokine was detected in all the samples of synovial fluid (range 50-22000 U/ml). IL-6 in synovial fluid was positively correlated (r = 0.58, P = 0.03) with the erythrocyte sedimentation rate in patients with inflammatory arthritis. In serum, the concentration of IL-6 was slightly elevated in some patients with rheumatoid arthritis. The results demonstrate that IL-6 is released into synovial fluid in joints affected by arthritis, and there appears to be an association between the levels of IL-6 and disease activity.     

Synovial fluid concentrations of interleukin-1 beta and proteoglycans are inversely related

Interleukin-1 beta (IL-1 beta) and proteoglycans have been quantified by radioimmunoassay (IL-1 beta) and enzyme linked immunosorbent assay (proteoglycans) in synovial fluids and sera from patients with rheumatoid arthritis (RA) and reactive arthritis. All fluids were also tested for their ability to influence proteoglycan metabolism in a cartilage explant culture system. Synovial fluid IL-1 beta concentrations were inversely related to proteoglycan concentrations in samples from both RA and reactive arthritis patients (P less than 0.002 for all patients). There was no statistically significant relation between immunoreactive IL-1 beta concentration and proteoglycan synthesis or degradation in explants cultured in synovial fluid containing medium. Synovial fluid IL-1 beta concentrations were not related to erythrocyte sedimentation rate or joint total leukocyte count. IL-1 beta was not detectable (limit 250 pg/ml) in any unextracted sera. Although it appears likely that IL-1 beta is involved in the inflammatory and degenerative processes in joint disease, our findings indicate that there is no simple positive relationship between immunoreactive levels of this cytokine in synovial fluid and liberation of proteoglycans from articular cartilage as reflected in synovial fluid proteoglycan concentration.     

Profile of Cytokines in Synovial Fluid Specimens from Patients with Arthritis. Interleukin 8 (IL-8) and IL-6 Correlate with Inflammatory Arthritides

The synovial fluid aspirated from patients with symptomatic arthritis was analyzed for the presence of tumor necrosis factor (TNF), interleukin 6 (IL-6) and interleukin 8 (IL-8). All three cytokines were found in both inflammatory and non-inflammatory arthritides: IL-8 levels ranged from less than 20 to 38,990 pg/ml, IL-6 from less than 10 to 72,300 pg/ml and TNF from less than 4 to 61 pg/ml. No inhibitors of cytokine activity were found. IL-8 and IL-6 were present in significantly higher levels in patients with inflammatory arthritis compared to patients with osteoarthritis, and there was significant correlation between the IL-6 and IL-8 levels. These findings document the presence of multiple cytokines in the synovial fluid specimens of patients with arthritis, and demonstrate that higher cytokine levels accompany inflammatory arthritis.     

A study of opioid peptides in synovial fluid and synovial tissue in patients with rheumatoid arthritis]

Authors have often experienced that psychological stress influences rheumatoid arthritis (RA). In addition, recent reports show a modulatory role for neuropeptide such as substance P in arthritis. These findings prompted us to study endogenous opioid peptides in RA, which are found mainly in the brain and have an effect on the central nervous system. We examined methionine-enkephalin (Met-enk), leucine-enkephalin (Leu-enk) and beta-endorphin (beta-end) in opioid peptides. We measured these peptides in plasma and synovial fluid samples obtained from 28 knees of 24 RA patients and the quantity in the synovial tissue of 13 knees. We also measured plasma and synovial fluid samples from patients with osteoarthritis of the knee and plasma samples from healthy candidates. Leu-enk and beta-end levels in synovial fluid were significantly higher than plasma levels only in RA. Larger quantity of Leu-end and beta-end were contained apparently in the synovial tissue than Met-enk. The synovial tissue with proliferative change tends to contain larger quantity of opioid peptides. These results indicate that the synovial tissue produces or secretes Leu-enk and beta-end and that opioid peptides are related to the degree of inflammation in RA.     

Measurement of interleukin-33 (IL-33) and IL-33 receptors (sST2 and ST2L) in patients with rheumatoid arthritis

The interleukin-33 (IL-33)/ST2 pathway has emerged as an intercellular signaling system that participates in antigen-allergen response, autoimmunity and fibrosis. It has been suggested that IL-33/ST2 signaling has been involved in the pathogenesis of rheumatoid arthritis (RA), because IL-33 and its receptor have been specifically mapped to RA synovium. The aim of this study was to determine the levels of IL-33 and sST2 in sera and synovial fluids in patients with RA. The serum level of IL-33 was significantly higher in patients with RA (294.9 ± 464.0 pg/mL) than in healthy controls (96.0 ± 236.9 pg/mL, P = 0.002). The synovial fluid level of IL-33 was significantly higher in RA patients than in osteoarthritis patients. The level of serum sST2 was higher in RA patients than in healthy controls (P = 0.042). A significant relationship was found between the levels of IL-33 and IL-1β (r = 0.311, P = 0.005), and IL-33 and IL-6 (r = 0.264, P = 0.017) in 81 RA patients. The levels of IL-33, sST2 and C-reactive protein decreased after conventional disease-modifying antirheumatic drugs treatment in 10 patients with treatment-na?ve RA. Conclusively, IL-33 is involved in the pathogenesis of RA and may reflect the degree of inflammation in patients with RA.     

Sensitive ELISA for interleukin-6. Detection of IL-6 in biological fluids: synovial fluids and sera

A monoclonal antibody and an affinity purified polyclonal antibody, both raised against recombinant human IL-6, have been employed in an ELISA procedure to quantitate human IL-6. Both antibodies were very potent in neutralizing the biological activity of recombinant as well as natural human IL-6. The monoclonal antibody was used as the capture antibody whilst the polyclonal antibody, in biotinylated form, was used as the detecting antibody in combination with a streptavidin horseradish peroxidase conjugate and a signal amplification system. The detection limit for natural as well as recombinant IL-6 was 1 pg/ml. A good correlation was found between the ELISA and the B9 biological assay when IL-6 was measured in crude culture supernatants, in synovial fluids of rheumatoid arthritis patients and in the sera of patients with diverse diseases. Immunoprecipitation of IL-6, produced by different cell types, such as monocytes, endothelial cells and smooth muscle cells or derived from biological fluids, such as the serum of a patient with septic shock or the synovial fluid of a rheumatoid arthritis patient, revealed in every case only molecules in the molecular weight range of 21,000-26,000.     

IL-17、MMP-3在类风湿关节炎患者滑膜液及血浆中的表达及意义

目的:分析类风湿关节炎(RA)患者滑膜液及血浆中白细胞介素-17(IL-17)、基质金属蛋白酶-3(MMP-3)的水平及其临床意义.方法:应用酶联免疫吸附法(ELISA)检测RA患者滑膜液及血浆中IL-17及MMP-3的水平,分析IL-17及MMP-3与临床指标的关系.结果:RA患者滑膜液IL-17及MMP-3水平明显...     

Interleukin-2 in rheumatoid arthritis: production of and response to interleukin-2 in rheumatoid synovial fluid, synovial tissue and peripheral blood.

Several aspects of interleukin-2 (IL-2) generation and function were studied employing mononuclear cells from synovial fluid (SF), synovial tissue (ST) and peripheral blood (PB) of patients with rheumatoid arthritis (RA). Decreased PHA stimulated IL-2 production by lymphocytes from rheumatoid ST, SF (P less than 0.02), and PB (P less than 0.01) was observed when compared to normal blood and SF of patients with gout. The proliferative response of rheumatoid lymphocyte blasts exposed to exogenous IL-2 was also defective (P less than 0.05-0.001). This defect was greater in SF than in rheumatoid PB (P less than 0.05-0.001). In addition to the proliferative response, the effect of IL-2 on interferon-gamma (IFN-gamma) production was also examined. Rheumatoid lymphocytes from both PB and SF produced less IFN-gamma after overnight treatment with IL-2 than did normal PB lymphocytes. This decreased IFN-gamma induction was discordant with the excellent enhancement by IL-2 of natural killer activity. Removal of adherent cells in synovial fluid did not correct this deficit. Abnormalities in the biology of IL-2 and IFN-gamma suggest that impaired T cell function could contribute to the immunopathogenesis of RA.     

Relationship between leukotriene B4 and immunological parameters in rheumatoid synovial fluids

Leukotriene B₄ (LTB₄) was measured in synovial fluid from 20 patients with rheumatoid arthritis and 15 patients with osteoarthritis. The level of LTB₄ was significantly higher in synovial fluid from rheumatoid arthritis patients as compared with synovial fluid from osteoarthritis patients. LTB₄ levels also significantly correlated with cell numbers, rheumatoid factor, and immune complexes in synovial fluid from rheumatoid arthritis patients. There was an inverse correlation between LTB₄ levels and complement components. The high-pressure liquid chromatography peak of immunoreactivity extracted from the synovial fluid occurred at a retention volume identical to that of authentic LTB₄. These results suggest that the increased level of this mediator in synovial fluid may contribute to perpetuation of inflammation and tissue destruction in rheumatoid arthritis.     

IL-15 promotes osteoclastogenesis via the PLD pathway in rheumatoid arthritis

Osteoclastogenesis plays an important role in joint destruction in rheumatoid arthritis (RA). IL-15 is a pleiotropic proinflammatory cytokine that appears to help mediate the pathological bone loss. This study was undertaken to explore the signaling molecules essential for osteoclastogenesis mediated by IL-15 in rheumatoid synovial fibroblasts. Expression of phospholipase D1 (PLD1) and osteoclast-related gene expression in synovial tissues and their modulation by treatment with IL-15 and different inhibitors in synovial fibroblasts of RA patients were evaluated using immunohistochemistry and quantitative polymerase chain reaction. The levels of IL-15 in serum and synovial fluid were measured by ELISA. The effects of IL-15 and phosphatidic acid (PA) on osteoclast formation were evaluated in cocultures of rheumatoid synovial fibroblasts and peripheral blood monocytes or monocytes alone in the presence of M-CSF and RANKL. The levels of RANKL and PLD1 but not PLD2 were upregulated significantly by IL-15, and the RANKL level was significantly upregulated by PA in rheumatoid synovial fibroblasts. Blocking PA production with 1-butanol and siRNA against PLD1 significantly inhibited the IL-15-stimulated expression of RANKL and PLD1. IL-15 levels were significantly higher in serum and synovial fluid from patients with RA than in osteoarthritis patients and healthy controls. IL-15 and PA induced osteoclast formation through the mitogen-activated protein kinases (MAPKs) and NF-κB signaling pathways. Activation of PLD1 contributes to IL-15-mediated osteoclastogenesis via the MAPKs and NF-κB signaling pathways in rheumatoid synovial fibroblasts. Our data suggest that PLD1 might be an efficient therapeutic strategy for preventing bone destruction in rheumatoid arthritis.     

Mechanism of T-Cell Activation by Mycobacterial Antigens in Inflammatory Synovitis

Earlier studies demonstrated enhanced proliferative responses to an acetone precipitable Mycobacterium tuberculosis (AP-MT) antigenic complex by T lymphocytes from the synovial fluid, compared with the peripheral blood, of patients with inflammatory synovitis, including rheumatoid arthritis. In contrast, decreased proliferation and interleukin 2 (IL-2) production in response to mitogens by synovial fluid lymphocytes from patients with rheumatoid arthritis has been demonstrated. In order to determine if IL-2 was produced in response to AP-MT, the peripheral blood and synovial fluid of patients with inflammatory arthritis were analysed by measuring proliferation and IL-2 production in response to AP-MT and tetanus toxoid. A reduction of IL-2 production relative to proliferation was observed in some, but not all, synovial fluids of patients who responded to the AP-MT. Nevertheless, antibodies to IL-2 as well as interleukin 4 (IL-4), significantly inhibited proliferation of synovial fluid lymphocytes by AP-MT. There was no inhibition by antibodies to interleukin 6 (IL-6). We conclude that AP-MT induced proliferation by synovial fluid lymphocytes is mediated by both IL-2 and IL-4.     

Caspase-1 Level in Synovial Fluid Is High in Patients with Spondyloarthropathy but Not in Patients with Gout

Activation of caspase-1 by NALP3 inflammasomes has been shown to be important in initiating acute gouty arthritis. The objectives of this study were to measure the levels of caspase-1 in synovial fluid in gout and various arthritides, and to elucidate the clinical significance of caspase-1 levels in synovial fluid. Caspase-1, IL-1β, IL-18, and uric acid were measured in synovial fluid from 112 patients with gout and other arthritides, such as rheumatoid arthritis, osteoarthritis, and spondyloarthropathy. Caspase-1 in synovial fluid from patients with crystal-induced arthritis, inflammatory arthritis, osteoarthritis, and spondyloarthropathy was 35.9 ± 86.7, 49.7 ± 107.7, 2.1 ± 7.0, and 152.6 ± 155.7 pg/mL, respectively. The mean level and the frequency of high levels (≥125 pg/mL) of caspase-1 in spondyloarthropathy were significantly higher than those in the other arthritides including gout. Caspase-1 was detectible in the synovial fluid of patients with the various arthritides. Contrary to our hypothesis, the caspase-1 level in the synovial fluid of patients with gout was not higher than in that of other arthritides. High levels of caspase-1 may be helpful in differentiating spondyloarthropathy from other arthritides.     

强直性脊柱炎和类风湿关节炎患者内皮素-1、降钙素基因相关肽水平的临床观察

目的：探讨内皮素-1（ET-1）、降钙素基因相关肽（CGRP）在强直性脊柱炎（AS）和类风湿关节炎（RA）病理生理过程中的作用。方法：用放射免疫法检测AS和RA患者血浆及关节液中ET-1、CGRP含量,并与健康志愿（HC）组进行比较。结果：AS、RA组血浆ET-1水平均明显高于HC组（P<0.01）;AS组和RA组血浆CGRP水平均与HC组无显著差异（P>0.05）;关节滑液中CGRP水平明显高于血浆（P<0.01）,ET-1水平明显低于血浆（P<0.01）。结论：ET-1、CGRP参与了AS、RA病理生理过程,但在AS、RA疾病过程中作用机制不同。     

Cytokines and the chronic inflammation of rheumatic disease. II. The presence of interleukin-2 in synovial fluids.

Sera and synovial fluids from patients with a variety of rheumatic diseases were assayed for interleukin-2 (IL-2) activity in a system utilizing the proliferative response of cultured human phytohaemagglutinin (PHA) T cell blasts. The synovial fluids from 14 rheumatoid arthritis, eight ankylosing spondylitis, three psoriatic arthritis and 11 osteoarthritis patients, all showed IL-2 activity. The amounts of IL-2 present in the fluids from different diseases were compared and ranged from 4.2 to 140.0 units/ml.     

Reduction of temporomandibular joint pain after treatment with a combination of methotrexate and infliximab is associated with changes in synovial fluid and plasma cytokines in rheumatoid arthritis

The aims were to investigate the effect of intravenous infusions of the tumor necrosis factor-alpha (TNF-alpha) antibody infliximab on symptoms and signs of temporomandibular joint (TMJ) involvement in relation to effects on synovial fluid and plasma proinflammatory TNF-alpha, interleukin-1beta (IL-1beta) and interleukin-6 as well as antiinflam matory soluble TNF receptor II (TNF-sRII), interleukin-1 receptor antagonist (IL-1ra), soluble IL-1 receptor II (IL-1sRII) and interleukin-10 (IL-10) in patients with active rheumatoid arthritis (RA). Nineteen patients with TMJ involvement taking methotrexate were included in the study. TMJ and general joint pain intensity as well as pain on mandibular movements, tenderness to digital palpation, pressure pain threshold and maximum mouth-opening capacity were assessed in a clinical examination. The effect of infliximab was assessed after 2 and 14 or 22 weeks. TMJ synovial fluid and venous blood were collected for cytokine analysis at all occasions while determination of erythrocyte sedimentation rate and C-reactive protein were performed at baseline and at long-term follow-up only. Reduction of TMJ pain was associated with raised levels of synovial fluid TNF-sRII and IL-1sRII as well as raised plasma levels of IL-1ra and IL-10. Decreased erythrocyte sedimentation rate was associated with decreased tenderness to digital palpation. Reduced general joint pain intensity was associated with reduced plasma levels of IL-6 and C-reactive protein. In conclusion, systemic treatment with a combination of infliximab and methotrexate reduces TMJ pain in RA in association with an increase in anti-inflammatory cytokines and receptors in synovial fluid and plasma.     

类风湿关节炎患者关节液中HSP72水平变化与疾病活动性及炎症因子水平相关性分析

目的观察类风湿关节炎(RA)患者关节液中热休克蛋白72(HSP72)的水平变化,并对其与疾病活动性相关指标和细胞因子之间的相关性进行分析。方法采用酶联免疫吸附法(ELISA)检测RA患者和骨关节炎(OA)患者关节液中HSP72、TNF-α、IL-6、IL-10的表达水平。结果活动期RA患者关节液中HSP72水平明显高于非活动期RA患者和OA对照组(P<0.01)。活动期RA患者关节液中TNF-α、IL-6的水平均高于非活动期RA患者和OA对照者(P<0.01),关节液中IL-10在各组之间无显著差异。RA患者关节液中HSP72的水平与血沉(ESR)、C反应蛋白(CRP)、风湿因子(RF)呈正相关;RA患者关节液中HSP72的水平与关节液中TNF-α、IL-6水平呈正相关。结论关节液中HSP72可能与RA的炎症相关,与RA病情活动有关。