A Vaccination Procedure Against Trypanosoma Cruzi Infection in Mice by Nonspecific Immunization

Abstract

There are previous reports dealing with vaccination against experimental infection with Trypanosoma cruzi in mice. They have varied from the use of avirulent, killed, or irradiated strains to subcellular materials and the use of other kinetoplastic flagellates (1, 2). Although these procedures have been promising, none of the methods presently studied has resulted in absolute protection under conditions of challenge with large numbers of parasites. The aim of the experiments reported here was to explore the possibility of protecting mice against T. cruzi infection by BCG immunization, a treatment that has been shown in other systems to enhance nonspecifically immunity (3–6). Mice of the Carworth Farm strain (CF1) aged 1.0 to 1.5 months were used uniformly throughout these experiments. Development of the T. cruzi infection was checked routinely by determination of parasites in blood every 5 days after challenge infection and histopathologic studies of the heart at the time of death.