Complement C5a human

Complement C5a human is an important terminal component of the complement cascade. It is a direct mediator of inflammation, and has been identified as a novel biomarker for pain and inflammation following surgery

A mixture of C5a (~35%) and C5a having an added methionyl residue at the amino terminus (~65%); exhibits biological activities similar to serum-derived C5a. C5a is a (11.2kDa) proteolytic fragment of the C5 α-chain through the action of C5 convertases in the classical and alternative complement pathway (C4b2a4b, C3bBb3b). C5a is an anaphylatoxin. It acts as an inflammatory chemoattractant. C5a stimulation of human neutrophils leads to STAT3 phosphorylation on Ser⁷²⁷. It mediates IL-8 release from bronchial epithelial cells. C5a anaphylatoxin activity on hepatocytes results indirectly from interaction with nonparenchymal cell via prostanoid secretion.

C5a, in addition to being a direct mediator of inflammation, can induce both IL-8 (interleukin-8) synthesis and high levels of IL-8 release from monocytes. This secondary effect serves as an amplification mechanism for inflammation at sites of infection or trauma. C5a exerts its effect through a G-protein coupled receptor, CD88.

Mol. Wt.: ~8.6 kDa (non-glycosylated, with glutathione attached to cysteine 27).

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