IL6 and rheumatoid arthritis: To check potential induction of FGF2 expression in RA resident cells, we purified synovial intimal resident fibroblast-like synoviocytes (FLS) from RA patients, and found that TGFβ but not IL-17 or TNFα induced FGF2 expression in these cells (Fig. 1D and Supplementary Fig. S1) while all the cytokines induced IL-6 expression (Supplementary Fig. S2).