integrin alpha with A domain integrin alpha-M leukocyte adhesion receptor MO1 CR3A cell surface glycoprotein MAC-1 subunit alpha neutrophil adherence receptor CD11b IUPHARobj:2452 CD11B protein CR-3 alpha chain Category=gene. Requested by=CL. CD11 antigen-like family member B ITGAM PR:000001012 An integrin alpha with A domain that is a translation product of the human ITGAM gene or a 1:1 ortholog thereof. They constitute subunits of the integrin alpha-M/beta-2 receptor. This receptor is implicated in various adhesive interactions of monocytes, macrophages and granulocytes as well as in mediating the uptake of complement-coated particles. It is also a receptor for fibrinogen, factor X and ICAM1.