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C3a (complement)
From Wikipedia, the free encyclopedia
C3a is one of the proteins formed by the cleavage of complement component 3; the other is C3b. C3a is a 77 residue anaphylatoxin that binds to the C3a receptor (C3aR), a class A G protein-coupled receptor. It plays a large role in the immune response.
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C3a molecules induce responses through the GPCR C3a receptor. Like other anaphylatoxins, C3a is regulated by cleavage of its carboxy-terminal arginine, which results in a molecule with lowered inflammatory function (C3a desarginine).[1]
C3a is an effector of the complement system with a range of functions including T cell activation and survival,[2] angiogenesis stimulation,[3] chemotaxis, mast cell degranulation,[4] and macrophage activation.[5] It has been shown to have both proinflammatory and anti-inflammatory responses, its activity able to counteract the proinflammatory effects of C5a.[6]
Initial research in mice demonstrating an effective treatment after stroke is leading to further investigation to determine whether application to humans has potential.[7]