The abundant expression of TGF-β1, 2, and 3 and of TGFBR1 and -2 in rat synovium, acts as a potent inducer of collagen-linked arthritis (CIA) [142], while the intra-articular injection of TGF-β1 or TGF-β2 induces symptoms typical of RA, resulting in synovial inflammation and hyperplasia [143]. The gene discussed is TGFB1; the disease is rheumatoid arthritis.