The influence of ecto-nucleotidases on Leishmania amazonensis infection and immune response in C57B/6 mice.

Previous results from our laboratory and from the literature have implicated the expression of ectonucleotidases in the establishment of Leishmania infection. In the present study we evaluated the correlation between ecto-nucleotidasic activity and the infectivity of L. amazonensis promastigotes tha...

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Detalles Bibliográficos
Autores: Testasicca, Miriam Conceição de Souza, Assis, Elisângela Aparecida de, Gomes, Rodrigo Saar, Silva, Eduardo de Almeida Marques da, Melo, Maria Norma, Fietto, Juliana Lopes Rangel, Afonso, Luís Carlos Crocco
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Brasil
Institución:Universidade Federal de Ouro Preto (UFOP)
Repositorio:Repositório Institucional da UFOP
Idioma:inglés
OAI Identifier:oai:repositorio.ufop.br:123456789/4579
Acceso en línea:http://www.repositorio.ufop.br/handle/123456789/4579
https://doi.org/10.1016/j.actatropica.2010.04.007
Access Level:acceso abierto
Palabra clave:Leishmania amazonensis
Adenosine
Macrophage
Chemokines
Virulence
Descripción
Sumario:Previous results from our laboratory and from the literature have implicated the expression of ectonucleotidases in the establishment of Leishmania infection. In the present study we evaluated the correlation between ecto-nucleotidasic activity and the infectivity of L. amazonensis promastigotes that were kept in culture for short or extended numbers of passages, a condition that is known to decrease parasite infectivity. We also analyzed the immune response associated with the infection by these parasites. As expected, we found that long-term cultured parasites induce the development of smaller lesions than the short-term cultured counterparts. Interestingly, long-term cultured parasites presented reduced ecto-nucleotidasic activity. In addition, cells recovered from animals infected with long-term cultured parasites produced higher amounts of IFN-_ and have smaller parasite load, after 8 weeks of infection. Furthermore, after 1 week of infection, there is increased expression of the chemokine CCL2 mRNA in animals infected with short-term cultured parasites. Finally, infection of peritoneal macrophages by these parasites also shows marked differences. Thus, while short-term cultured parasites are able to infect a greater proportion of macrophages, cells infected by long-term cultured parasites express higher amounts of CXCL10 mRNA, which may activate these cells to kill the parasites. We suggest that the enzymes involved in metabolism of extracellular nucleotides may have an important role in infection by L. amazonensis, by acting directly in its adhesion to target cells and by modulating host cell chemokine production.