Leukadherin-1, a specific agonist of the leukocyte surface integrin CD11b/CD18, increases CD11b/CD18-dependent cell adhesion to fibrinogen with an EC50 of 4 μM. Leukadherin-1 enhances leukocyte adhesion to ligands (such as ICAM-1) and vascular endothelium and thus reduces leukocyte transendothelial migration and influx to the injury sites. Leukadherin-1 suppresses innate inflammatory signaling.