Taken together, these data indicate that SB-HCC tumors develop a highly immune suppressive TME within 20–30 days of hydrodynamic plasmid injection, thereby re-capitulating this aspect of human HCC in which a highly immunosuppressive TME39 is associated with exhausted CD8+ T cells with reduced anti-tumor cytotoxicity40, 41, 42. The gene discussed is CD8A; the disease is hepatocellular carcinoma.