M1 polarization leads to the secretion of IL-6, IL-12, TNF-α, and inducible NO synthase (iNOS) to promote proinflammatory responses against infection79, whereas M2 polarization of liver macrophages can promote liver fibrosis by expressing anti-inflammatory cytokines and profibrogenic mediators, such as IL-6, IL-10, macrophage colony-stimulating factor (M-CSF), arginase 1 (Arg1), and platelet-derived growth factor (PDGF)-B80,81. The gene discussed is NOS2; the disease is Hepatic fibrosis.