Purified anti-human C5a/C5a(desArg)

C5, complement component 5, is a protein involved in the complement system. It is cleaved into C5a and C5b by the C3/C5 convertase. The smaller fragment C5a is an anaphylatoxin and is released into the fluid surroundings. C5a is a mediator of local inflammatory process. It induces the contraction of smooth muscle, increases vascular permeability and causes histamine release from mast cells and basophilic leukocytes. C5a also stimulates the locomotion of polymorphonuclear leukocytes (chemokinesis) and direct their migration toward sites of inflammation (chemotaxis). C5a contains 74 amino acids and is rapidly metabolised by a serum enzyme, carboxypeptidase B to a 73 amino acid form, C5a des-Arg. The major fragment C5b binds to the membrane initiating the spontaneous assembly of the late complement components, C5-C9, into the membrane attack complex.