Intercellular adhesion molecule 3 (ICAM3) also known as CD50 (Cluster of Differentiation 50), is a protein that in humans is encoded by the ICAM3gene.[3] The protein is constitutively expressed on the surface of leukocytes, which are also called white blood cells and are part of the immune system.[4][5] ICAM3 mediates adhesion between cells by binding to specific integrin receptors.[6] It plays an important role in the immune cell response through its facilitation of interactions between T cells and dendritic cells, which allows for T cell activation.[7][8] ICAM3 also mediates the clearance of cells undergoing apoptosis by attracting and binding macrophages, a type of cell that breaks down infected or dying cells through a process known as phagocytosis, to apoptotic cells.[6][9][10]
