IRF2 and hepatocellular carcinoma: The composition of the immune infiltrate was examined with fluorescence-activated cell sorting (FACS) on isolated immune cells from β-M-pT3 and β-M-IRF2 HCC, which demonstrated significant increases in total CD4+ T cells with decreases in T regulatory cell populations in the β-M-IRF2 mice (Supplementary Fig. 17c; Supplementary Fig. 18a).