title: The immune response to toxocariasis does not modify susceptibility to Mycobacterium tuberculosis infection in BALB/c mice.
abstract: Mycobacterium tuberculosis and helminth infections coincide geographically and are classically described as TH1 and TH2 pathologies. There is much interest in exploring how concurrent worm infections might alter immune responses to mycobacterial infection. To explore this issue, mice were infected with Toxocara canis and co-infected with M. tuberculosis. Mice infected with M. tuberculosis had high numbers of neutrophils and mononuclear cells within the alveolar spaces, with increased parenchymal interferon (IFN)-gamma levels. However, in Toxocara-infected mice we detected increased eosinophil numbers in bronchoalveolar lavage fluid (BALF) and increased parenchymal levels of interleukin (IL)-5. In co-infected mice the BALF demonstrated enhanced eosinophil influx with decreased neutrophil and mononuclear cell accumulation. However, co-infected mice had similar mycobacterial proliferation in their lungs accompanied by similar histopathological changes and similar cytokine/nitric oxide production compared with Mycobacterium-only-infected mice. Our results suggest that T. canis infection does not necessarily lead to increased susceptibility to pulmonary tuberculosis.
authors.affiliation: Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo-Ribeirão Preto, São Paulo, Brazil. frantz@fcfrp.usp.br
authors.forename: Fabiani Gai
authors.initials: FG
authors.lastname: Frantz
authors.forename: Rogério Silva
authors.initials: RS
authors.lastname: Rosada
authors.forename: Walter Miguel
authors.initials: WM
authors.lastname: Turato
authors.forename: Camila Matias
authors.initials: CM
authors.lastname: Peres
authors.forename: Arlete Aparecida Martins
authors.initials: AA
authors.lastname: Coelho-Castelo
authors.forename: Simone Gusmão
authors.initials: SG
authors.lastname: Ramos
authors.forename: David Michael
authors.initials: DM
authors.lastname: Aronoff
authors.forename: Célio Lopes
authors.initials: CL
authors.lastname: Silva
authors.forename: Lúcia Helena
authors.initials: LH
authors.lastname: Faccioli
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000469:parasitology; D016207:Cytokines / Q000276:immunology; D004198:Disease Susceptibility / Q000276:immunology / Q000382:microbiology; D005260:Female; D008168:Lung / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology*; D009569:Nitric Oxide / Q000737:chemistry / Q000378:metabolism; D013154:Spleen / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*; D017166:Toxocara canis / Q000276:immunology*; D014120:Toxocariasis / Q000276:immunology* / Q000382:microbiology; D014376:Tuberculosis / Q000276:immunology* / Q000469:parasitology
chemical_list: D016207:Cytokines; D009569:Nitric Oxide