title: Gastrointestinal infection with Mexican TcI Trypanosoma cruzi strains: different degrees of colonization and diverse immune responses.
abstract: Mexican Ninoa and Queretaro (Qro) TcI strains of Trypanosoma cruzi have shown different degrees of virulence, and the two strains produce heterogeneous immune responses in the hearts of infected mice. This work shows that the same strains can invade the intestine by an intraperitoneal route and establish an infection, mainly in the colon. The three segments of the small intestine (duodenum, jejunum and ileum) were infected to a lesser degree than the colon. Despite the fact that parasites were predominantly found in the colon, an obvious inflammatory reaction was observed in the submucosal layer along the entire intestinal tract, with the virulent Qro strain causing significantly more areas of higher immune infiltration. A clear recruitment of CD4⁺ and CD8⁺ T lymphocytes to the mesenteric ganglia was observed during infection with the virulent strain. Macrophages were also differentially distributed in the gastrointestinal tract. These later cells infiltrated fewer amastigote nests in the mice infected with the Qro strain than in the mice infected with the Ninoa strain. When IFN-γ, TNF-α, and IL-4 levels were measured, an increase in these cytokines was observed compared with the uninfected mice. The role of these inflammatory reactions in the pathogenesis of Chagas enteropathy is also discussed in this paper.
authors: Departamento de Inmunología. Instituto de Investigaciones Biomédicas. Universidad Nacional Autónoma de México, Mexico City 04510. besgu@biomedicas.unam.mx
authors: Bertha
authors: B
authors: Espinoza
authors: Natalia
authors: N
authors: Solorzano-Domínguez
authors: Andrea
authors: A
authors: Vizcaino-Castillo
authors: Ignacio
authors: I
authors: Martínez
authors: Ana L
authors: AL
authors: Elias-López
authors: José Antonio
authors: JA
authors: Rodríguez-Martínez
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D005260:Female; D005767:Gastrointestinal Diseases / Q000276:immunology* / Q000378:metabolism / Q000469:parasitology*; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D015847:Interleukin-4 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D060888:Real-Time Polymerase Chain Reaction; D014349:Trypanosoma cruzi / Q000276:immunology* / Q000472:pathogenicity*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D016207:Cytokines; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; D007371:Interferon-gamma