Modulatory Effects of Interferons on Trypanosoma cruzi Infections

This chapter discusses the exploration of the possible interactions of the interferon system with Trypanosoma cruzi. Trypanosoma cruzi is the etiologic agent of Chagas’ disease, or American trypanosomiasis. Natural infections with this unicellular parasite are initiated by metacyclic trypomastigote forms present in the fecal fluid of the reduviid insect vectors. While in the circulation, released trypomastigotes may be ingested by blood-sucking reduviid insects. A series of transformations in the insect gut leads to the presence of a metacyclic trypomastigotes in the fecal fluid of the insects, thus completing the life cycle of the parasite. Mice of different genetic background were used in experiments with the Peru and the two other isolates, a condition which could also account for some of the noted differences. Antibodies directed against the parasite could work in conjunction with the interferons to aid in host resistance.