CD38 and acute myeloid leukemia: Since the expression of TIGIT, PVRIG, CD39, and CD38 on NK cell subpopulations was altered in AML in comparison to HDs, we further investigated the co-expression of TIGIT, PVRIG, PD-1, LAG-3, CD39, CD73, CD38, and CD69 on the total NK cells as well as within the different NK cell subpopulations.