Pathways of complement (C3) activation in rabbits infected with Trypanosoma evansi

Immunoelectrophoresis was used to evaluate the pathways of complement (C3) activation with sera from rabbits infected with Trypanosoma evansi. C3 activation via the classical pathway was of a higher magnitude than via the alternative pathway using both the intact parasite and soluble parasite antigens. This observation indicates that although the two pathways may be activated during infection, the activation of the classical pathway may be dominant in a host's response to a T. evansi infection during both the early and late stages of the disease.