One of the integrin superfamily of adhesion molecules (lymphocyte function-related antigen-1, CD11a/CD18, αL 1170 aa; β, 95kDa, 769 aa), found on lymphocytes and that binds ICAM-1. Deficiency of the β subunit (CD18) causes leucocyte adhesion deficiency (LAD) syndrome with serious immunodeficiency and a poor prognosis. The LFA-1 class of adhesion molecules have a common β subunit and include Mac-1 (αM, CD11b, 1152 aa) and p150,95 (αX, CD11c, 150 kDa, 1163 aa); they are also defective in severe forms of LAD. Mac-1 (Mo-1 in earlier literature) is the complement C3bi receptor (CR3) and is present on mononuclear phagocytes and on neutrophils; p150,95 is less well characterized, but is particularly abundant on macrophages. Integrin αD/β2 (CD11d, 1162 aa) is a receptor for ICAM3 and VCAM1 and may be involved in clearing lipoproteins from atherosclerotic plaques and phagocytosis of blood-borne particles.
Subjects: Medicine and Health — Chemistry.