Complement component C3-derived neutrophil chemotactic factors purified from exudate of rat carrageenin-induced inflammation.

Two neutrophil chemotactic factors have been purified from the exudate of chronic-phase of rat carrageenin-induced inflammation. Both the factors were derived from the third component of complement (C3); one was an NH2-terminal fragment (C3a) of alpha chain of C3 and another chemoattractant was a COOH-terminal fragment of beta chain, which was referred to as C3 beta c, on the basis of their molecular masses and NH2-terminal amino acid sequences. C3a exhibits potent chemotactic activity for rat neutrophils, and C3 beta c is a novel basic neutrophil chemoattractant with molecular mass of about 11 kDa, suggesting that both chemoattractants play a role in the neutrophil infiltration into inflammatory site of carrageenin-induced inflammation in rats.