Abstract: To investigate the proliferation of fibroblastlike synovial（FLS） cells in rheumatoid arthritis (RA) patients in vitro and the immunosuppressive effect of thalidomide, total glucosides of paeony (TGP) and T614 on them. Methods: Synovial specimens were obtained from 6 patients with RA by arthroscopy and blindly needle biopsy, or by pumping synovial fluid on knees. FLS cells were identified in vitro by histopathological dyeing, immunohistochemical analysis and fluorescenceactivated cell sorting（FCS）method for cell surface molecules respectively. The synoviocyte proliferation was measured by MTT colorimetric assay and the survival fraction（SF）of FLS was evaluated in the presence or absence of thalidomide, TGP and T614. The expression of cfos mRNA was examined by semiquantitative RTPCR in FLS cells of RA patients. Results: The identified synovial cells in patients with RA were FLS（Vimentin and Fibronectin expression positive）either cultured with agents or not. The SF of all FLS interfered by thalidomide, TGP orT614 was lower than vacant contrast without agents in RA shown by MTT assay（P<0.05）. Thalidomide operated the strongest, whereas T614 the weakest in the three agents（P<0.05）. Thalidomide at physiological doses and TGP in high concentration demonstrated marked dosedependent inhibitory curses on FLS proliferation efficiency（P<0.05）. It was detected by semiquantitative RTPCR that cfos mRNA of RAFLS expressed highly and decreased obviously when incubation with thalidomide, TGP or T614. In all the three agents, thalidomide downregulated cfos expression markedly（P<0.05）. Conclusion: There are no distinct activated unlimited viability in RAFLS without being stimulated by proinflammatory cytokine in vitro. The results have confirmed our suggestion that thalidomide, TGP and T614 possess the immunosuppressive effect to synovitis by modulating the cell proliferation and cfos mRANA gene transcription directly in RAFLS.

Key words: Rheumatoid arthritis, Synovial membrane, Fibroblasts, Thalidomide, Total glucosides of paeony, T614类风湿关节炎（reumatoid athritis,RA)