Complement component 5a (C5a).

School of Biomedical Sciences, University of Queensland, Brisbane, Australia.
The international journal of biochemistry & cell biology (Impact Factor: 4.89). 05/2009; 41(11):2114-7. DOI: 10.1016/j.biocel.2009.04.005
Source: PubMed

ABSTRACT The 74 amino acid glycoprotein, complement component 5a (C5a), is a potent pro-inflammatory mediator cleaved enzymatically from its precursor, C5, upon activation of the complement cascade. C5a is quickly metabolised by carboxypeptidases, forming the less potent C5adesArg. Acting via a classical G protein-coupled receptor, CD88, C5a and C5adesArg exert a number of effects essential to the innate immune response, while their actions at the more recently discovered non-G protein-coupled receptor, C5L2 (or GPR77), remain unclear. The widespread expression of C5a receptors throughout the body allows C5a to elicit a broad range of effects. Thus, C5a has been found to be a significant pathogenic driver in a number of immuno-inflammatory diseases, making C5a inhibition an attractive therapeutic strategy.

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