Unlike the crosstalk between NK cells and HSCs in alcoholic liver fibrosis, the present study indicated that NK cells may directly affect hepatocytes to exert protective roles against liver steatosis via IFN-γ which inhibits lipogenesis-associated gene expression in hepatocytes (Figures 1C,D, 2B,C, 4A and 6C,D), which was further confirmed by using IFN-γ-deficient GKO mice (Figures 3A–C). Here, IFNG is linked to fatty liver disease.