类风湿关节炎患者自身抗体及关节损伤因子检出的临床意义

Detection and significance of auto-antibodies and arthritis damaging factors in rheumatoid arthritis

目的:检测类风湿关节炎(rheumatoid arthritis,RA)患者关节损伤因子及多种自身抗体,探讨其与RA发病间的关联性。方法:采用酶联免疫吸附试验(ELISA)法检测15例RA患者血清和滑膜液中关节损伤相关因子基质金属蛋白酶3(matrix metalloproteinases 3,MMP3)和基质金属蛋白酶组织抑制因子1(tissue inhibitor of metalloproteinase 1,TIMP-1)、骨破坏因子——核因子κB受体活化因子配基(receptor activator of NF-κB ligand,RANKL)和其保护性抑制剂骨保护素(osteoprotegerin,OPG)的表达。检测6例RA患者的sIL-6和sIL-6Rα、sgp130表达水平,同时设骨关节炎(osteoarthritis,OA)为对照组(6例)及正常对照组(8例)。分析22例RA患者临床常用的检测指标,包括类风湿因子、抗环瓜氨酸多肽抗体、葡萄糖-6-磷酸异构酶及23例RA患者抗胶原Ⅱ抗体的表达,并以OA患者为对照;针对用合成的EBV肽段和人HLA-DR4肽段检测和分析15例RA患者抗EBV肽段和抗HLA-DR4肽段抗体的阳性率。结果:RA患者关节腔滑膜液中MMP3和TIMP1表达异常,滑膜液MMP3/TIMP1比值显著高于相应的血清相应比值(P<0.001)。与OA组相比,RA患者血清及滑膜液中RANKL水平升高(P<0.05),RA患者血清中RANKL/OPG比值高于RA患者滑膜液(P<0.05)。RA患者体内IL-6信号系统表达异常,其滑膜液中sIL-6Rα水平高于OA组(P<0.05),而天然拮抗剂sgp130的血清水平则显著低于OA组血清中(P<0.001),RA组滑膜液及血清sIL-6Rα/sgp130比值均异常升高。检测患者自身抗体发现,RA患者组与OA患者组间,血清类风湿因子-IgM、抗环瓜氨酸多肽抗体、葡萄糖-6-磷酸异构酶阳性比例及滑膜液抗胶原Ⅱ的IgG型抗体的水平差异有统计学意义(P<0.05)。此外,80%的RA患者被检出为HLA-DR4阳性,且其体内存在EBVgp110、EBV EBNA1(IgG)及EBV VCA(IgG)抗体。结论:RA患者异常的炎症因子及自身抗体表达可能介导患者关节炎症及骨平衡的紊乱,是导致患者发生关节病变和破坏的因素之一。对于HLA-DR4阳性的患者,因RA的发生、发展与"病毒的分子模拟"机制密切相关,抗EBV抗体检测对这类患者更具临床意义。

Objective To detect the arthritis damaging factors and auto-antibodies in rheumatoid arthritis （RA） patients,and to study the correlation between these factors and the pathogenesis of RA. Methods Enzyme-linked immunosorbent assay （ELISA） was used to detect serum and synovial fluid level of joint damaging related factors including matrix metalloproteinase 3 （MMP3）, tissue inhibitor of metalloproteinase 1 （TIMP-1）, receptor activator of NF-KB Ligand （RANKL） and osteoprotegerin （OPG） in 15 cases with RA. The expression levels of sIL-6, sIL-6R α and sgpl30 were analyzed in 6 cases of RA, 6 cases of OA, and 8 healthy volunteers （control）. Clinical indexes including rheumatoid factor,anti-CCP antibody, GPI, anti-C 11 antibody were examined in 23 patients with RA, and anti-EBV peptide antibodies were determined in 15 of the patients. Results MMP3 and TIMP1 levels were significantly higher in synovial fluid than in serum in RA patients （P〈0.001）. Serum and synovial fluid RANKL level was higher in RA than that in OA group （P〈0.05）, and the ratio of RANKL/OPG was higher in RA serum than those in RA synovial fluid. Compared with OA Group, RA patients had abnormal expression of IL-6 signal system, with a higher level of IL-6 and sIL-6Rct in synovial fluid as well as the higher ratio of sIL-6R odsgp 130 in both synovial fluid and serum （P〈0.05）. Serum levels of sgpl30 （natural antagonist） was significantly lower in RA group than that in OA group （P〈0.001）. The levels of serum rheumatoid factor （IgM）, anti-CCP antibody, GPI, and anti-C ]I antibody （IgG） were significantly higher in RA patients than those in OA patients （P〈0.05）. In addition, 80% of RA patients were HLA-DR4 positive, and had auto-antibodies against EBVgp110, EBV EBNA 1 （IgG） and EBV VCA （IgG）. Conclusions Abnormal expression of inflammatory cytokines and auto- antibodies might mediate the joint damage and osteoclast/osteoblast imbalance in RA. Since molecular modelling of EB virus correlates closely with the pathogenesis and development of RA, detection of anti-EBV antibodies may have important clinical significance in HLA-DR4- positive RA patients.