ABSTRACT
Objective To assess the association of synovial cyclic citrullinated peptide(CCP)expression with T helper 17(Th17) cells/Regulatory T cells (Treg) imbalance,the histological and clinical features of synovitis in rheumatoid arthritis (RA).Methods CCP expression in synovial specimens from 39 patients with RA and 35 controls was detected by immunohistochemistry assay(IH) using 6×His tagged anti-CCP single chain fragment V (ScFv) antibodies,which were generated by pHEN2 phagemid recombinant antibodies display system.The frequencies of Th17/Treg cells in the peripheral blood mononuclear cells (PBMCs) were determined by flow cytometry (FCM).Th17/Treg cells associated cytokines were analyzed by enzyme-linked immunosorbent assay (ELISA).The histological scores and clinical features of synovitis were included in the study.Chi-square test and ANOVA were used for statistical analysis.Results ① The prevalences of synovial C CP expression were significantly different between RA group and the control(76.9％ and 11.4％ respectively,X2=31.9,P＜0.01).② The frequencies of Th17 cells,Th17/Treg ratio,Th17 cells associated cytokines as IL-6,IL-17a,IL-23,TNF-α,and the Treg cells associated cytokines TGF-31,the serum and synovial fluid anti-CCP antibodies in the RA patients with synovial CCP positive expression were significantly higher in RA patients with CCP positive than those with CCP negative.Disease activity score DAS28 index and histological features quantified variations of the synovial biopsy specimens (synoviocyte hyperplasia,focal aggregates of lymphocytes,and diffuse infiltrat(e)s of lymphocytes) in RA were higher in synovial CCP positive expression patients than in the negative.Conclusion Synovial CCP expression is strongly associated with the Th17/Treg imbalance and synovitis,which may play a crucial role in the pathogenesis of RA.