IL17A and rheumatoid arthritis: Accumulating studies showed that IL-17 and IL-17-producing T helper (Th17) cells played a critical role during the development and progression of RA (Kim et al., 2017) and Lee’s study exhibited that IL-17 upregulated the expression of TLR3 by STAT3 pathways in fibroblast-like synoviocytes of RA (Lee et al., 2014).