Role of complement in chemotaxis: study of a localized infection.

A model of Escherichia coli-induced pyelonephritis was used to study the effect of complement depletion in an organ-specific, nonimmunological inflammatory lesion in rats. In this model of a local infection, which can be considered to be nonspecific inflammatory stimulus, the depletion of complement by the administration of a purified cobra venom factor did not alter the course of the disease. There were minor differences when the results from complement-depleted and normocomplementemic animals were compared, but the composition of the inflammatory infiltrate was not greatly altered. Therefore, the presence of C3 and a functional complement system are relatively unimportant factors in determining the characteristics of the inflammatory response in a localized infection-induced lesion.