Chemokine Receptors

Abstract

Chemokine receptors are seven-transmembrane proteins expressed on neutrophils, lymphocytes, dendritic cells, and many other cell types. They function to mediate migration of leukocytes to the sites of injury and infection in response to a gradient concentration of chemokines, a group of small proteins that specifically bind the chemokine receptors. Chemokine receptors belong to the G-protein-coupled seven-transmembrane receptor superfamily, which has more than 600 members that use the heterotrimeric G proteins to initiate signals. Nineteen chemokine receptors have been identified and cloned, and these receptors have been classified into four subfamilies (CXC, CC, CX3C, and C) based on the chemokine subclass specificity. In addition to the mediation of migration of leukocytes to the inflammatory sites (chemotaxis), chemokine receptors play a role in leukocyte homing, human immunodeficiency virus entry, angiogenesis, tumor growth and metastasis, development, and inflammation of the central nervous system.