TNF and Hepatic fibrosis: Meng et al. [22] have demonstrated that IL-17 promotes liver fibrosis through two independent mechanisms: (1) IL-17 stimulates Kupffer cells (KCs), which in turn secrete the cytokines IL-6, IL-1β, TNF-α and TGF-β1, which stimulate the activation of HSCs; (2) IL-17 directly stimulates the STAT3 signaling pathway, activates HSCs to express collagen I, and promotes the activated HSCs to transform into pro-fibrogenic myofibroblasts, resulting in the synthesis of large amounts of extracellular matrix.