A human killer inhibitory receptor specific for HLA-A1,2.

Killer inhibitory receptors (KIRs) are transmembrane glycoproteins, expressed on NK cells and a small subset of T cells, that inhibit cell-mediated cytotoxicity upon binding to polymorphic MHC class I determinants on target cells. Although human KIRs specific for HLA-C and HLA-B molecules have been characterized, none have been shown to interact with HLA-A. Here we demonstrate that a member of the KIR cDNA family, designated NKAT4, encodes a 70-kDa receptor specific for HLA-A3.