Rat Intercellular Adhesion Molecule 4 (ICAM4) Protein

Background

ICAM4 (Intercellular Adhesion Molecule 4) is a transmembrane glycoprotein that belongs to the immunoglobulin (Ig) superfamily and is primarily expressed on erythrocytes (red blood cells). ICAM4 functions as an adhesion molecule, playing a significant role in cell-to-cell interactions, particularly between red blood cells and other cell types. It is also known as the Landsteiner-Wiener blood group antigen and is encoded by the ICAM4 gene, which is located on chromosome 19. The primary physiological role of ICAM4 is in mediating interactions with other cells, notably endothelial cells, leukocytes, and macrophages, contributing to the cellular processes in circulation and immune response. ICAM4 is part of the ICAM family of molecules, which includes ICAM1, ICAM2, ICAM3, and ICAM5. ICAM molecules are generally involved in leukocyte-endothelial cell adhesion and signaling pathways that regulate inflammation and immune responses. ICAM4, although sharing structural similarities with these other molecules, is unique in its specificity to erythrocytes and its function in erythrocyte interactions, notably through binding with integrins such as α4β1 and αV integrins found on various immune cells.