Since CD8+ T lymphocytes can aggravate liver fibrosis by secreting cytokines to activate hepatic stellate cells [31, 32], GITRL depletion in liver progenitor cells may attenuate liver fibrosis indirectly by reducing the total number of CD8+ T lymphocytes and their cytokine secretion. The gene discussed is TNFSF18; the disease is Hepatic fibrosis.