CD11b

CD11b is a protein that in humans is encoded by the ITGAM gene. It is also known as integrin alpha M (ITGAM) and is a component of the integrin protein family.

Structure

CD11b is a type of integrin alpha chain. It combines with the beta 2 chain (CD18) to form a leukocyte-specific integrin referred to as macrophage receptor 1 ('Mac-1'), or inactivated-C3b (iC3b) receptor 3 ('CR3'). The alpha M beta 2 integrin is important in the adherence of neutrophils and monocytes to stimulated endothelium, and also in the phagocytosis of complement coated particles.

Function

The protein encoded by the ITGAM gene is the integrin alpha M chain. Integrins are heterodimeric integral membrane proteins composed of an alpha chain and a beta chain. This I-domain containing alpha integrin combines with the beta 2 chain (CD18) to form a leukocyte-specific integrin referred to as macrophage receptor 1 ('Mac-1'), or inactivated-C3b (iC3b) receptor 3 ('CR3'). The alpha M beta 2 integrin is important in the adherence of neutrophils and monocytes to stimulated endothelium, and also in the phagocytosis of complement coated particles.

Clinical significance

Mutations in the ITGAM gene are associated with susceptibility to systemic lupus erythematosus type 6 (SLEB6). SLEB6 is a systemic autoimmune disease characterized by the production of autoantibodies that form immune complexes and are deposited within tissues, which can cause damage and dysfunction.

See also

• Cluster of differentiation
• Integrin
• Systemic lupus erythematosus

External links

• ITGAM at the US National Library of Medicine Medical Subject Headings (MeSH)