Killer cell immunoglobulin-like receptor 2DL4 (KIR2DL4)

Receptor for non-classical significant histocompatibility class Ib HLA-G molecules. Recognizes HLA-G in complex with B2M/beta-2 microglobulin and a nonamer self-peptide (peptide-bound HLA-G-B2M).

In decidual NK cells, binds peptide-bound HLA-G-B2M complex and triggers NK cell senescence-associated secretory phenotype as a molecular switch to encourage vascular remodeling and fetal growth in early pregnancy (PubMed:23184984, PubMed:29262349, PubMed:16366734). May play a role in balancing endurance and antiviral-immunity in maternal-fetal interface by keeping in check the effector functions of NK, CD8+ T cells and B cells (PubMed:10190900, PubMed:16366734).