TIGIT and HIV-1 infection: Of these, NKG2A−NKG2C+NK cells are not conducive to suppressing HIV-1 replication in acute HIV-1 infection, partly because the levels of TIGIT expressed on these adaptive NKG2A−NKG2C+NK cells were far higher than that on NKG2A+NKG2C−NK cells (Figure 4).