Cluster of differentiation 11b (CD11b) acts as a receptor for complement component C3 degradation product, iC3b. CD11b interacts with β2 chain (ITGB2) to form a leukocyte integrin (MAC-1 or complement receptor 3 (CR3)), which in turn plays a crucial role in adherence of neutrophils and monocytes to stimulated endothelium. Mutation in the gene increases the risk of susceptibility to systemic lupus erythematosus (SLE) and acute inflammatory demyelinating polyradiculoneuropathy (AIDP).
