Figure 1.

Generation of Adaptive natural killer (NK) cells. The expansion of adaptive NK cells requires three signals: (1) appropriate receptor engagement in the context of a viral peptide (such as HLA-E and NKG2C, with other unknown viral or self-peptides and receptors likely involved), (2) co-stimulation and (3) proinflammatory cytokines. This engagement with a virally infected cell leads to the generation of diverse, highly functional subsets of NK cells with differing degrees of epigenetic remodeling.