The leukocyte immunoglobulin-like receptors (LILR) are a family of receptors possessing extracellular immunoglobulin domains.[1]
They are also known as CD85, ILTs and LIR, and can exert immunomodulatory effects on a wide range of immune cells.[2] The human genes encoding these receptors are found in a gene cluster at chromosomal region 19q13.4.
A subset of LILR recognise MHC class I (also known as HLA class I in humans). The LILR family is a cluster of paired receptors with both activating and inhibitory functions.[3] Of these, the inhibitory receptors LILRB1 and LILRB2 show a broad specificity for classical and non-classical MHC alleles with preferential binding to b2m-associated complexes. In contrast, the activating receptors LILRA1 and LILRA3 prefer b2m-independent free heavy chains of MHC class I, and in particular HLA-C alleles.[4]