IL17A and rheumatoid arthritis: According to the research, Yi Shen Juan Bi pill could affect the activation and differentiation of OCs caused by RA by regulating the phenotypic balance of T cells, upregulating the percentage of Tregs, such as IL-10 and TGF-β1 levels, and downregulating the percentage of Th1 and Th17 cells, such as IFN-γ and IL-17A levels.