Overall, these studies have revealed multiple layers of NK cell-virus interplay in lentivirus infection including: (1) KIR-HLA; (2) induction of CD2 and NKG2-related molecules; (3) interaction of Fc-receptor bearing NK cells and Ab-opsonized virus infected cells; and (4) development of HIV/SIV-specific NK cell memory-like responses. Here, CD2 is linked to lentivirus infection.