Infection by the Sylvio X10/4 clone of Trypanosoma cruzi: relevance of a low-virulence model of Chagas' disease

Abstract

The physiopathology of Chagas' disease has been largely defined in murine infections with virulent strains which partially represent parasite diversity. This report reviews our studies with Sylvio X10/4 parasites, a Trypanosoma cruzi clone that induces no acute phase but in C3H/He mice leads to chronic myocarditis resembling the human disease.

Chagas Disease: Still Many Unsolved Issues

“…How can we explain why patients with greater proinflammatory responses to T. cruzi are those with lower heart parasite control? An interesting possibility is that T. cruzi persistence in the heart (and in other relatively immunoprivileged locations) is not merely the consequence of a defective local immune response but that it, to a large extent, derives from the parasite's ability to remain unnoticed inside the structural cells, safe from the effector activity of cytotoxic CD8 + T cells [64]. Illustrative evidence of this possibility is shown in Figure 3, where an amastigote nest can be observed amid myocardial fibers in a mouse infected for more than 200 days, that is, in an animal with a high level of anti- T. cruzi immune effector activity.…”

“…The tissue section was stained with hematoxylin-eosin. Bar corresponds to 100  μ m (reproduced from C. R. F. Marinho, Microbes and Infection [64] with permission from Elsevier).…”

A flow cytometer-based method to simultaneously assess activity and selectivity of compounds against the intracellular forms of Trypanosoma cruzi

“…Yet, mice experimentally infected with natural T. cruzi isolates frequently exhibit features of chronic infection that better reproduces the course of human Chagas disease than these high-virulence strains (Marinho et al, 2009). It is pertinent to develop reproducible and sensitive assays using T. cruzi strains of moderate virulence as the one used here.…”

Expanding the knowledge of the chemical structure of glycoconjugates from Trypanosoma cruzi TcI genotype. Contribution to taxonomic studies

“…The Silvio X10 clone 1 strain is a member of the T. cruzi I group that finds frequent use in research models, both in vivo and in vitro (Marinho et al 2009, Messenger et al 2012. It was originally isolated from a Rodnius prolixus bug used in a xenodiagnosis test to a Chagas disease patient from the State of Pará in Brazil (Silveira et al 1979).…”