Mind the gap: lack of association between KIR3DL1*004/HLA‐Bw4-induced natural killer cell function and protection from HIV infection.

Several combinations of genes encoding KIR3DL1 alleles and their HLA‐Bw4 ligands have been linked with favorable outcomes upon exposure to or infection with human immunodeficiency virus (HIV). Some protective KIR3DL1/HLA‐Bw4 combinations confer elevated natural killer (NK) cell functional potential. The K562‐stimulated functionality of NK cells from KIR3DL1*004/HLA‐Bw4 and control genotype carriers was assessed by flow cytometry and found to be higher in KIR3DL1*004/HLA‐Bw4 carriers. However, a comparison of the frequency of this combined genotype among HIV‐exposed uninfected and HIV‐infected subjects revealed no between‐group differences. Thus, despite its ability to license NK cells, KIR3DL1*004/HLA‐Bw4 is not associated with a reduced risk of infection.