LILRB4

LILRB4 leukocyte immunoglobulin-like receptor B4 is an immune checkpoint molecule belonging to the leukocyte immunoglobulin-like receptor family B subfamily member. It consists of an extracellular immunoglobulin-like domain, a transmembrane domain, and a cytoplasmic domain containing immunoreceptor tyrosine-based inhibitory motifs (ITIMs). LILRB4 is expressed on a variety of immune cells, including monocytes, macrophages, mast cells, B cells, natural killer cells, T cells, and dendritic cells, and has the function of regulating immune cell activity and promoting tumor immune escape. LILRB4 inhibits mast cell activation by binding to ligands such as integrin αvβ3 and transmits inhibitory signals through its cytoplasmic domain containing ITIMs to inhibit immune cell activity. In addition, LILRB4 may also inhibit the NF-κB signaling pathway by recruiting SHP1, which may play a role in the occurrence of atherosclerosis. The expression and function of LILRB4 are of great significance in different diseases, especially in cancer treatment. Antibodies targeting LILRB4 may help to inhibit tumor immune escape and improve the effect of immunotherapy. Therefore, LILRB4 is a potential target in immunotherapy research, and the study of its structure and function is helpful for developing new treatment strategies.