ICAM1
Description
The ICAM1 (intercellular adhesion molecule 1) is a protein-coding gene located on chromosome 19.
ICAM-1 (Intercellular Adhesion Molecule 1), also known as CD54 (Cluster of Differentiation 54), is a protein encoded by the ICAM1 gene in humans. This gene produces a cell surface glycoprotein typically found on endothelial cells and immune system cells. ICAM-1 binds to integrins of the CD11a/CD18 or CD11b/CD18 type and acts as a receptor for rhinovirus, enabling it to enter respiratory epithelium. As a member of the immunoglobulin superfamily, ICAM-1 is a transmembrane protein with an extracellular domain, a transmembrane domain, and a cytoplasmic domain. Its structure is characterized by extensive glycosylation, with the extracellular domain containing multiple loops formed by disulfide bridges. The dominant secondary structure is the beta sheet, suggesting potential dimerization domains within ICAM-1. ICAM-1 is continuously present in low concentrations on leukocytes and endothelial cells but increases significantly upon cytokine stimulation. It is induced by interleukin-1 (IL-1) and tumor necrosis factor (TNF) and is expressed by the vascular endothelium, macrophages, and lymphocytes.
ICAM1, a ligand for the leukocyte adhesion protein LFA-1, plays a critical role in leukocyte trans-endothelial migration. Its engagement during this process triggers the formation of endothelial apical cups, a crucial step in leukocyte movement through the endothelium. This process is mediated by the activation of ARHGEF26/SGEF and RHOG.
ICAM1 is also known as BB2, CD54, P3.58.
