The ICRF44 monoclonal antibody specifically reacts with the 165 kDa human adhesion glycoprotein CD11b, which forms, together with the 95 kDa CD18 （integrin β2） a complex known as Mac-1.
CD11b is expressed on the surface of activated lymphocytes, a subset of natural killer cells, granulocytes, and monocytes.
It functions as a receptor in cell-cell and cell-matrix interactions and as a receptor for iC3b, ICAM-1, ICAM-2, and ICAM-3 intercellular adhesion molecules.
