title: Differential infectivity and immunopathology in murine experimental infections by two natural clones belonging to the Trypanosoma cruzi I lineage.
abstract: Immunopathology of Chagas' disease in Balb/c mice infected with 2 Trypanosoma cruzi clones, belonging to the T. cruzi I lineage and presenting different in vitro virulence (P/209 cl1 > SO34 c14) was compared. In the acute phase, evading mechanisms such as parasite-induced lymphocyte polyclonal activation and T cell immunosuppression were higher in mice infected with the clone giving a higher parasitaemia (P/209 cl1). A similar increase of non-specific isotypes was observed in both infections with IgG2a prevalence. Interestingly, CD8+ cell hypercellularity and lymphocyte immunosuppression were observed during the chronic phase (245 days post-infection) in mice infected by the most virulent clone. In the same way, the parasite-specific antibody response was more intense in P/209 cl1-infected mice over the acute phase. During the chronic phase this response remarkably dropped down in SO34 cl4-infected mice exclusively. Finally, P/209 cl1-infected mice presented a more severe inflammation and tissue damage in heart and quadriceps than SO34 cl4-infected mice. This comparative study showed differences between the two clones: a higher virulence in vivo being clearly associated with a greater ability to induce evasion mechanisms and severe tissue damage.
authors.affiliation: Institut de Recherche pour le Développement, IRD, UR 008 Pathogénie et Epidémiologie des Trypanosomatidés, 911 Av. Agropolis, BP 64501, 34394 Montpellier Cedex 5, France.
authors.forename: E
authors.initials: E
authors.lastname: Garzon
authors.forename: F
authors.initials: F
authors.lastname: Genna
authors.forename: M F
authors.initials: MF
authors.lastname: Bosseno
authors.forename: J
authors.initials: J
authors.lastname: Simony-La Fontaine
authors.forename: M
authors.initials: M
authors.lastname: Radal
authors.forename: D
authors.initials: D
authors.lastname: Sereno
authors.forename: F
authors.initials: F
authors.lastname: Mathieu-Daude
authors.forename: A
authors.initials: A
authors.lastname: Ouaissi
authors.forename: S F
authors.initials: SF
authors.lastname: Brenière
mesh_terms: D000818:Animals; D002460:Cell Line; D002598:Chagas Cardiomyopathy / Q000473:pathology; D014355:Chagas Disease / Q000276:immunology / Q000469:parasitology* / Q000473:pathology; D005347:Fibroblasts; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D009220:Myositis / Q000469:parasitology; D013997:Time Factors; D014349:Trypanosoma cruzi / Q000235:genetics* / Q000472:pathogenicity*
chemical_list: D007074:Immunoglobulin G