CD8A and acute myeloid leukemia: Consistently, CD8+ T cells of PBMCs were reactivated after co-culturing with PD-L1-KO HL-60 cS5 cells or exposure to toripalimab (Fig. 6h, i), giving support that PD-L1 inhibition in AML might restore CD8+ T cell activation suppressed by STAT5.