Trypanosoma cruzi: Experimental immunization of mice

Abstract

The evolution of histopathological lesions and parasitemia were compared in young Rockland mice with prior immunization and adult Rockland mice without prior immunization, challenged with virulent Trypanosoma cruzi. Recovery of parasites from the animals was demonstrated by injecting their tissues into C3H mice. It was not possible to recover parasites in 30% of the young immunized mice challenged with 5 × 10 4 virulent T. cruzi. The level of parasitemia was much lower in the immunized groups than in the nonimmunized. The histopathological lesions had a tendency to heal in the immunized mice; the tissues of those challenged with 5 × 10 4 parasites appeared histologically normal 120 days after the challenge. The severity of these lesions apparently was related to the size of the immunizing and challenging doses.