KLRB1 and neoplasm: We found that although NKG2C+ NK cell functions were slightly decreased in CMV seropositive compared with seronegative individuals, both NKR‐P1A+ and NKR‐P1A‒ NK cells from CMV seropositive individuals showed the same levels of IFN‐γ production (IFN‐γ+) (Figure 5A) and degranulation (CD107a+) (Figure 5B) when stimulated with PMA/I or K562 tumor cells.