Killer cell immunoglobulin-like receptor 3DL1 (KIR3DL1)

Killer cell immunoglobulin-like receptor 3DL1 (KIR3DL1) is a highly polymorphic, inhibitory receptor primarily expressed on natural killer (NK) cells and some T cell subsets in humans. It plays a crucial role in regulating immune responses by interacting with specific human leukocyte antigen (HLA) class I molecules. KIR3DL1 functions as an inhibitory checkpoint for NK cells, recognizing HLA-A and HLA-B molecules that express the Bw4 epitope. Upon binding, its ITIM motifs become phosphorylated, leading to the recruitment of phosphatases that inhibit NK-cell-mediated lysis of healthy self-cells. Polymorphisms in KIR3DL1 and its HLA ligands are associated with susceptibility/resistance to various diseases including infections, autoimmune disorders, cancers, and influence outcomes after transplantation due to effects on immune surveillance.

Other names

p70 natural killer cell receptor clones CL-2/CL-11Natural killer-associated transcript 3MHC class I NK cell receptorHLA-Bw4-specific inhibitory NK cell receptorCD158 antigen-like family member E

ITIM motifs become phosphorylated by Src family kinases, which recruits phosphatases SHP-1/SHP-2 that dephosphorylate key signaling proteins downstream of activating receptors.