IFNG and B-cell chronic lymphocytic leukemia: Stimulation of CLL-derived NK cells with a combination of PMA and Ionomycin, which mimics activation but bypasses any dependence on extracellular receptors, resulted in increased degranulation, activation and IFNγ production compared to HC NK cells (Fig. 5A–C), which demonstrates there is no intrinsic defect in effector programs in CLL-derived NK cells.