Integrin alpha-L/beta-2 is a receptor for ICAM1, ICAM2, ICAM3 and ICAM4. Is involved in a variety of immune phenomena including leukocyte-endothelial cell interaction, cytotoxic T-cell mediated killing, and antibody dependent killing by granulocytes and monocytes. Mice expressing a null mutation of the alpha-L subunit gene demonstrate impaired tumor rejection and impaired leukocytes recruitment.