CD4 and fatty liver disease: Wang et al. [17] selected CD4+ T cells to explore the immunoregulatory effect of MSCs on NASH and found that MSCs alleviated hepatic steatosis, inflammation, and hepatic fibrogenesis by inhibiting the multiplication and activation of CD4+IFN-γ+ T cells and CD4+IL-6+ T cells in the spleen of NASH mice; however, it did not influence CD4+IL-17+ T cell activity.