RESUMO
BACKGROUND: Toxoplasma gondii is a protozoan with worldwide distribution and triggers a strong Th1 immune response in infected susceptible hosts. On the contrary, most helminth infections are characterized by Th2 immune response and the use of helminth-derived antigens to regulate immune response in inflammatory disorders has been broadly investigated. OBJECTIVES: The aim of this study was to investigate whether treatment with Strongyloides venezuelensis antigen extract (SvAg) would alter immune response against T gondii. METHODS: C57BL/6 mice were orally infected with T gondii and treated with SvAg, and parasitological, histological and immunological parameters were investigated. RESULTS: It was observed that SvAg treatment improved survival rates of T gondii-infected mice. At day 7 post-infection, the parasite load was lower in the lung and small intestine of infected SvAg-treated mice than untreated infected mice. Remarkably, SvAg-treated mice infected with T gondii presented reduced inflammatory lesions in the small intestine than infected untreated mice and decreased intestinal and systemic levels of IFN-γ, TNF-α and IL-6. In contrast, SvAg treatment increased T gondii-specific IgA serum levels in infected mice. CONCLUSIONS: S venezuelensis antigen extract has anti-parasitic and anti-inflammatory properties during T gondii infection suggesting as a possible alternative to parasite and inflammation control.
Assuntos
Antígenos de Helmintos/uso terapêutico , Strongyloides/imunologia , Toxoplasmose/tratamento farmacológico , Animais , Citocinas/análise , Citocinas/sangue , Feminino , Imunoglobulina A/análise , Imunoglobulina A/sangue , Intestino Delgado/parasitologia , Intestino Delgado/patologia , Pulmão/parasitologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Carga Parasitária , Toxoplasmose Animal/tratamento farmacológicoRESUMO
Starting from an outbreak of a human cutaneous leishmaniasis, we proposed to investigate the natural dog infection, in rural and urban area of Uberlândia, Minas Gerais, Brazil. The dog were submitted to clinical, hemoparasitological and sorological diagnosis (indirect fluorescent antibody reaction): from 429 domestic dogs examined, 100 from the rural area and 329 from the urban area. The indirect fluorescent antibody reaction showed that 1% of the dogs from the rural area and 10,6% of dogs from the urban area were reagent for Leishmania. These findings seem to indicate that the dog represents an important role as reservatory of the infection, contributing with dissemination and formation of new foci of the endemic disease in the urban area.
A partir de um surto de Leishmaniose Tegumentar (LT) humana no Triângulo Mineiro e Alto Paranaíba, propusemos-nos investigar a infecção natural em cães em áreas rural e urbana do município de Uberlândia - Minas Gerais. Os cães foram submetidos a exames clínico, hemoparasitológico e sorológico (reação de imunofluorescência indireta). Foram examinados 429 cães sendo 100 da área rural e 329 da área urbana. A RIF1 demonstrou que 1% dos animais da zona rural e 10,6% dos animais da área urbana foram reagentes para Leishmania. Este achado parece indicar que a infecção canina na região de estudo é ativa e que o cão poderá representar um importante papel como reservatório da infecção, podendo participar na disseminação e formação de novos focos da endemia também em área urbana.