Leukocyte Immunoglobulin Like Receptor Subfamily B, Member 4 (LILRB4) ELISA Kit for Horse

This gene is a member of the leukocyte immunoglobulin-like receptor (LIR) family, which is found in a gene cluster at chromosomal region 19q13.4. The encoded protein belongs to the subfamily B class of LIR receptors which contain two or four extracellular immunoglobulin domains, a transmembrane domain, and two to four cytoplasmic immunoreceptor tyrosine-based inhibitory motifs (ITIMs). The receptor is expressed on immune cells where it binds to MHC class I molecules on antigen-presenting cells and transduces a negative signal that inhibits stimulation of an immune response. It is thought to control inflammatory responses and cytotoxicity to help focus the immune response and limit autoreactivity. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

LILRB1: Receptor for class I MHC antigens. Recognizes a broad spectrum of HLA-A, HLA-B, HLA-C and HLA-G alleles. Receptor for H301/UL18, a human cytomegalovirus class I MHC homolog. Ligand binding results in inhibitory signals and down-regulation of the immune response. Engagement of LILRB1 present on natural killer cells or T-cells by class I MHC molecules protects the target cells from lysis. Interaction with HLA-B or HLA-E leads to inhibition of the signal triggered by FCER1A and inhibits serotonin release. Inhibits FCGR1A-mediated phosphorylation of cellular proteins and mobilization of intracellular calcium ions. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: Receptor, misc.; Membrane protein, integral

Chromosomal Location of Human Ortholog: 19q13.4

Cellular Component: cytoplasm; plasma membrane; extracellular region; integral to membrane; external side of plasma membrane

Molecular Function: MHC class I receptor activity; protein homodimerization activity; MHC class I protein binding; HLA-A specific inhibitory MHC class I receptor activity; SH2 domain binding; HLA-B specific inhibitory MHC class I receptor activity; protein phosphatase 1 binding

Biological Process: immune response-inhibiting cell surface receptor signaling pathway; positive regulation of apoptosis; signal transduction; negative regulation of cell cycle; negative regulation of interferon-gamma biosynthetic process; negative regulation of serotonin secretion; negative regulation of alpha-beta T cell activation; negative regulation of T cell proliferation; T cell proliferation during immune response; receptor internalization; negative regulation of interferon-gamma production; negative regulation of T cell mediated cytotoxicity; interferon-gamma production; positive regulation of cytolysis; negative regulation of tumor necrosis factor biosynthetic process; Fc receptor mediated inhibitory signaling pathway; defense response to virus; regulation of immune response; negative regulation of calcium ion transport; negative regulation of mononuclear cell proliferation; negative regulation of endocytosis; negative regulation of natural killer cell mediated cytotoxicity; response to virus; negative regulation of cytokine secretion during immune response; positive regulation of transcription from RNA polymerase II promoter; positive regulation of defense response to virus by host