The release of soluble vasoactive material from Trypanosoma congolense in intraperitoneal diffusion chambers

Millipore diffusion chambers containing living or lysed Trypanosoma congolense cause a local inflammatory reaction when implanted intraperitoneally into rats. Empty chambers do not do this. The active material is of low molecular weight and is possibly peptide in nature. It appears to act by increasing local vascular permeability. It was found to be neither chemotactic nor cytotoxic in several assay systems. It is considered that this material may contribute to the pathogenesis of T. congolense infection in animals.