HIV-1 Control by NK Cells via Reduced Interaction between KIR2DL2 and HLA-C∗12:02/C∗14:03

Natural killer (NK) cells control viral infection in part through the interaction between killer cell immunoglobulin-like receptors (KIRs) and their human leukocyte antigen (HLA) ligands. We investigated 504 anti-retroviral (ART)-free Japanese patients chronically infected with HIV-1 and identified two KIR/HLA combinations, KIR2DL2/HLA-C∗12:02 and KIR2DL2/HLA-C∗14:03, that impact suppression of HIV-1 replication. KIR2DL2+ NK cells suppressed viral replication in HLA-C∗14:03+ or HLA-C∗12:02+ cells to a significantly greater extent than did KIR2DL2− NK cells in vitro. Functional analysis showed that the binding between HIV-1-derived peptide and HLA-C∗14:03 or HLA-C∗12:02 influenced KIR2DL2+ NK cell activity through reduced expression of the peptide-HLA (pHLA) complex on the cell surface (i.e., reduced KIR2DL2 ligand expression), rather than through reduced binding affinity of KIR2DL2 to the respective pHLA complexes. Thus, KIR2DL2/HLA-C∗12:02 and KIR2DL2/HLA-C∗14:03 compound genotypes have protective effects on control of HIV-1 through a mechanism involving KIR2DL2-mediated NK cell recognition of virus-infected cells, providing additional understanding of NK cells in HIV-1 infection. [Display omitted] •Two HLA-KIR combinations were identified with protective effects in HIV-1 control•Peptide-HLA binding influences NK cell recognition of target cells via KIR2DL2•Peptide-HLA binding directly influences NK cell antiviral function•CTL-selected escape mutations influence NK cell antiviral function KIR-HLA interactions play an important role in the antiviral functions of NK cell during HIV-1 infection. Lin et al. investigated HLA-KIR interplay in HIV-1 infection and found that two HLA-KIR combinations are associated with lower plasma viral load. Antiviral activity of KIR2DL2+ NK cell is, therefore, fine-tuned by peptide-HLA binding.