FGF2 and kidney disorder: Both subtypes of macrophages could secret pathogenic chemokines and cytokines, such as interleukin-1 (IL-1), IL-6 and tumor necrosis factor-α (TNF-α) in the M1 and IL-10, transforming growth factor-β (TGF-β1) and fibroblast growth factor-2 (FGF-2) in the M2, which mediate proinflammatory and profibrotic effects in kidney diseases 14-16.