FGF1 and rheumatoid arthritis: High levels of FGF1 can be found in multiple tissues of inflammatory arthritic joints, including bone, cartilage, synovium, ligament, and tendon.482 Besides, most T cells in synovial tissue in rheumatoid arthritis express FGFR1 for FGF1.483 FGF1 can enhance IL-2 production and activation of NF-κB in T cells.483 Rossini et al.484 found that both FGF1 and FGFR1 are expressed in filtrating lymphocytes and macrophages during the renal inflammation, and FGFR1 is highly expressed in tubules, suggesting that FGF1 might have both autocrine and paracrine functions.