While applying antibody/cytokine-mediated in vitro stimulation of primed naïve NK cells confirmed these data (Figure 1), more physiological stimulation of naïve NK cells or infection-primed ADAPko NK cells with YAC-1 target cells uncovered impaired cytotoxicity of ADAP-deficient NK cells while their capacity to produce IFN-γ was not affected (Figure 2). This evidence concerns the gene FYB1 and infection.