IL17A and rheumatoid arthritis: Most of these inflammatory cytokines, including IFN‐γ, TNF‐α, and IL‐17A, can induce the proinflammatory characteristics of FLS by increasing IL‐6 production (an important proinflammatory cytokine in RA pathogenesis that can induce Th17 differentiation)[13] (Figure S1, Supporting Information).