OBJECTIVETo study the regulatory effect of fengshiqing (FSQ) on interleukin 4 (IL-4), gamma-interferon (gamma-IFN), macrophage inflammatory protein 1alpha (MIP-1alpha) and collagen type II antibody (C II Ab) in serum and supernatant of synovial cell culture of rat with rheumatoid arthritis (RA), to explore the mechanism of action of clearing-heat and activating blood method for treatment of RA.

METHODSRA rat model was induced by C II Ab combined with Freund's complete adjuvant, and the levels of IL-4, gamma-IFN, MIP-1alpha and C II Ab in serum and supernatant of synovial cell were detected by ELISA.

RESULTSAs compared with the normal group, serum level of C II Ab in the model group was significantly higher (P < 0.01), serum and supernatant contents of IL-4 on the 14th and 28th day of modeling were lower and those of gamma-IFN and MIP-1alpha were higher, the difference showed statistical significance (P < 0.05 or P < 0.01). After being treated with FSQ and IL-4 contents in serum and supernatant as well as MIP-1alpha in supernatant restored on the 14th day (P < 0.05 or P < 0.01), while all the indexes restored on the 28th day.

CONCLUSIONFSQ could evidently up-regulate the level of IL-4 and down-regulate that of MIP-1alpha in serum and local synovial membrane in RA rats, and shows a suppressive trend of gamma-IFN, so as to maintain the Th1/Th2 equilibrium, suppress the cellular and humoral immune response in the local synovial membrane, and alleviate the chronic changes of arthritis, synovitis and vasculitis.