KLRC2 and cytomegalovirus infection: Expanded proportions of mature (CD56dimCD57+NKG2A-CD158b+) NKG2C+ NK cells persist after viral clearance (Foley et al., 2012b) and memory-like expansions of NKG2C+CD57+ NK cells are also observed in R+/D+ patients with subclinical HCMV infection (Foley et al., 2012a).