KLRK1 and B-cell chronic lymphocytic leukemia: Further, we observed a concurrent significant reduction in the expression of the activating receptor NKG2D on the surface of NK cells obtained from the CLL patients (6.92 ± 2.6% of NK cells expressing NKG2D in CLL patients versus 27.26 ± 7.11% in HDs, p = 0.037, Figure 6c).