SH2D1B and cytomegalovirus infection: This NK2 subpopulation featured high expression of NKG2C KLRC2) and low expression of PLZF (PLZF), FcεRγ (FCER1G), EAT-2 (SH2D1B), and SYK (SYK), which are used as markers for memory NK cells in the context of human cytomegalovirus (HCMV) infection [37, 64].