Trypanosoma cruzi strains in the Calomys callosus: parasitemia and reaction of intracellular forms with stage-specific antibodies in the acute and chronic phase of infection and after immunosuppression

Autor(es)

Taniwaki, Noemi Nosomi ^[1] ; Goncalves, Viviane Martinelli ^{[2, 1]} ; Romero, Julianna Kesselring ^[1] ; da Silva, Claudio Vieira ^{[2, 3]} ; da Silva, Solange ; Mortara, Renato Arruda ^[2]

Afiliação do(s) autor(es)

^[1] Adolfo Lutz Inst, Electron Microscopy Unit, BR-01246902 Sao Paulo - Brazil

^[2] Fed Univ Sao Paulo UNIFESP, Dept Microbiol Immunol & Parasitol, BR-04023062 Sao Paulo - Brazil

^[3] Univ Fed Uberlandia, Dept Immunol, Inst Biomed Sci, BR-38400902 Uberlandia, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Parasitology Research; v. 109, n. 2, p. 431-440, AUG 2011.
• Citações Web of Science: 4

Resumo

An experimental model for chronic Chagas disease was developed to investigate whether reactivation is influenced by the genetic origin of Trypanosoma cruzi isolates. In addition, we examined whether the distribution of T. cruzi stage-specific epitopes, as defined by monoclonal antibodies (Mab), raised against mammalian-stage parasite forms, exhibited comparable distribution patterns in Calomys callosus myocardium during the acute phase and after reactivation of the infection. Animals were infected with parasites of the G (T. cruzi I), Y (T.cruzi II) or CL strains (T. cruzi VI). Heart sections were labelled with the Mabs 2C2, 1D9, 2B7, 3B9 and 4B9, which react with carbohydrate epitopes on Ssp-4, a major amastigote surface glycoprotein. Mab 1D9 and 2B7 showed polymorphic distributions over amastigotes among animals infected with the G, Y or CL strains. Mab 3B2, which recognises a non-carbohydrate epitope in flagellated forms, showed an active state of parasite dissemination in the myocardium of C. callosus that were infected with Y or CL strains and then immunosuppressed after 6 or 12 months. C. callosus infected with the G strain (T. cruzi I) displayed absence of amastigote nests in the heart after immunosuppression. Our results permit us to suggest that parasites of the G strain may be more sensitive to the immune response, since we could not find either evidence of parasitemia or amastigote nests. Conversely, parasites from the Y and CL strains appeared able to escape the immune response, as evidenced by an inflammatory infiltrate and disseminated infection after immunosuppression. (AU)

• Processo FAPESP: 07/00860-9 - Morfologia do miocárdio de Calomys callosus:infeccao crônica por cepas das duas principais linhagens filogenéticas de Trypanosoma cruzi, seguida de imunossupressão
• Beneficiário: Noemi Nosomi Taniwaki
• Modalidade de apoio: Auxílio à Pesquisa - Regular