As reported in Figure 2A, following the stimulation with TGF-β + IL-6 for 6 days, the collagen I mRNA expression was significantly increased in both RA-FLSs (p = 0.002) and HC-FLSs (p = 0.002) more than the UT-cells. This evidence concerns the gene TGFB1 and rheumatoid arthritis.