title: The TcI and TcII Trypanosoma cruzi experimental infections induce distinct immune responses and cardiac fibrosis in dogs.
abstract: Trypanosoma cruzi infection may be caused by different strains with distinct discrete typing units (DTUs) that can result in variable clinical forms of chronic Chagas disease. The present study evaluates the immune response and cardiac lesions in dogs experimentally infected with different T. cruzi strains with distinct DTUs, namely, the Colombian (Col) and Y strains of TcI and TcII DTU, respectively. During infection with the Col strain, increased levels of alanine aminotransferase, erythrocytes, haematocrit and haemoglobin were observed. In addition, CD8+ T-lymphocytes isolated from the peripheral blood produced higher levels of interleukin (IL)-4. The latter suggests that during the acute phase, infection with the Col strain may remain unnoticed by circulating mononuclear cells. In the chronic phase, a significant increase in the number of inflammatory cells was detected in the right atrium. Conversely, infection with the Y strain led to leucopoenia, thrombopoenia, inversion of the ratio of CD4+/CD8+ T-lymphocytes and alterations in monocyte number. The Y strain stimulated the production of interferon-γ by CD4+ and CD8+ T-lymphocytes and IL-4 by CD8+ T-cells. In the chronic phase, significant heart inflammation and fibrosis were observed, demonstrating that strains of different DTUs interact differently with the host.
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Ana Luiza Cassin
authors.initials: AL
authors.lastname: Duz
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Paula Melo de Abreu
authors.initials: PM
authors.lastname: Vieira
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Bruno Mendes
authors.initials: BM
authors.lastname: Roatt
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Rodrigo Dian Oliveira
authors.initials: RD
authors.lastname: Aguiar-Soares
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Jamille Mirelle de Oliveira
authors.initials: JM
authors.lastname: Cardoso
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Flávia Carvalho Bitencourt de
authors.initials: FC
authors.lastname: Oliveira
authors.affiliation: Laboratório de Pesquisas Clínicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Levi Eduardo Soares
authors.initials: LE
authors.lastname: Reis
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Washington Luiz
authors.initials: WL
authors.lastname: Tafuri
authors.affiliation: Laboratório de Pesquisas Clínicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Vanja Maria
authors.initials: VM
authors.lastname: Veloso
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Alexandre Barbosa
authors.initials: AB
authors.lastname: Reis
authors.affiliation: Laboratório de Imunopatologia, Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brasil.
authors.forename: Cláudia Martins
authors.initials: CM
authors.lastname: Carneiro
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism; D014355:Chagas Disease / Q000097:blood / Q000276:immunology* / Q000473:pathology; D002908:Chronic Disease; D004195:Disease Models, Animal; D004285:Dogs; D004906:Erythrocyte Count; D005355:Fibrosis / Q000276:immunology / Q000469:parasitology; D005434:Flow Cytometry; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D015847:Interleukin-4 / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000737:chemistry; D018655:Lymphocyte Count; D009206:Myocardium / Q000737:chemistry / Q000276:immunology / Q000473:pathology*; D010641:Phenotype; D014349:Trypanosoma cruzi / Q000276:immunology* / Q000378:metabolism
chemical_list: D006454:Hemoglobins; D015847:Interleukin-4; D000410:Alanine Transaminase