title: Differential Activation of Human Monocytes and Lymphocytes by Distinct Strains of Trypanosoma cruzi.
abstract: BACKGROUND
  Trypanosoma cruzi strains are currently classified into six discrete typing units (DTUs) named TcI to VI. It is known that these DTUs have different geographical distribution, as well as biological features. TcI and TcII are major DTUs found in patients from northern and southern Latin America, respectively. Our hypothesis is that upon infection of human peripheral blood cells, Y strain (Tc II) and Col cl1.7 (Tc I), cause distinct immunological changes, which might influence the clinical course of Chagas disease.
  
  
  RESULTS
  We evaluated the infectivity of CFSE-stained trypomastigotes of Col cl1.7 and Y strain in human monocytes for 15 and 72 hours, and determined the immunological profile of lymphocytes and monocytes exposed to the different isolates using multiparameter flow cytometry. Our results showed a similar percentage and intensity of monocyte infection by Y and Col cl1.7. We also observed an increased expression of CD80 and CD86 by monocytes infected with Col cl1.7, but not Y strain. IL-10 was significantly higher in monocytes infected with Col cl1.7, as compared to Y strain. Moreover, infection with Col cl1.7, but not Y strain, led to an increased expression of IL-17 by CD8+ T cells. On the other hand, we observed a positive correlation between the expression of TNF-alpha and granzyme A only after infection with Y strain.
  
  
  CONCLUSIONS
  Our study shows that while Col cl1.7 induces higher monocyte activation and, at the same time, production of IL-10, infection with Y strain leads to a lower monocyte activation but higher inflammatory profile. These results show that TcI and TcII have a distinct immunological impact on human cells during early infection, which might influence disease progression.
authors.affiliation: Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Luísa M D
authors.initials: LM
authors.lastname: Magalhães
authors.affiliation: Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Agostinho
authors.initials: A
authors.lastname: Viana
authors.affiliation: Laboratório de Biologia do Trypanosoma cruzi e doença de Chagas, Departamento de Parasitologia, Instituto de Ciências Biológicas, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Egler
authors.initials: E
authors.lastname: Chiari
authors.affiliation: Laboratório de Biologia do Trypanosoma cruzi e doença de Chagas, Departamento de Parasitologia, Instituto de Ciências Biológicas, Belo Horizonte, Minas Gerais, Brazil; Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil.
authors.forename: Lúcia M C
authors.initials: LM
authors.lastname: Galvão
authors.affiliation: Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Belo Horizonte, Minas Gerais, Brazil; Programa de Pós-Graduação em Medicina e Biomedicina, Instituto de Ensino e Pesquisa, Hospital Santa Casa, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Gollob
authors.affiliation: Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Walderez O
authors.initials: WO
authors.lastname: Dutra
mesh_terms: D000328:Adult; D014355:Chagas Disease / Q000276:immunology* / Q000469:parasitology; D005260:Female; D006801:Humans; D016753:Interleukin-10 / Q000276:immunology; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D009000:Monocytes / Q000276:immunology*; D014349:Trypanosoma cruzi / Q000502:physiology*; D055815:Young Adult
chemical_list: C508609:IL10 protein, human; D016753:Interleukin-10