FAS and HIV-1 infection: NK cells target HIV-1 infection by directly killing infected cells through the killer immunoglobulin-like receptor (KIR)-mediated recognition of target cells, degranulation resulting in granzyme and porforin release, the Fas-Fas ligand pathway, antibody-dependent cell-mediated cytotoxicity (ADCC), and modulating adaptive immune responses with IFN-γ production [50].