This observation is consistent with studies showing that coculture of CLL cells with NK cells from healthy donors decreases NKG2D expression, NK cell cytotoxicity and IFNγ production, indicating that CLL cells are able to hamper NK cell functions and create a hyporesponsive phenotype and further supporting that the reduced cytotoxicity of CLL-derived NK cells is not due to intrinsic defects in their effector programs [39]. Here, KLRK1 is linked to B-cell chronic lymphocytic leukemia.