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. [ https://www.uniprot.org/uniprot/P11215 ]