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 NH 2-terminal fragment (C3a) of α chain of C3 and another chemoattractant was a COOH-terminal fragment of β chain, which was referred to as C3βc, on the basis of their molecular masses and NH 2-terminal amino acid sequences. C3a exhibits potent chemotactic activity for rat neutrophils, and C3βc 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.