E-NTPDase (ecto-nucleoside triphosphate diphosphohydrolase) of Leishmania amazonensis inhibits macrophage activation

Leishmania amazonensis, the causal agent of diffuse cutaneous leishmaniasis, is known for its ability to modulate the host immune response. Because a relationship between ectonucleotidase activity and the ability of Leishmania to generate injury in C57BL/6 mice has been demonstrated, in this study w...

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Detalhes bibliográficos
Autores: Souza Vasconcellos, Raphael de, Gomes, Rodrigo Saar, Carvalho, Luana Cristina Faria de, Fietto, Juliana Lopes Rangel, Afonso, Luís Carlos Crocco
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2014
País:Brasil
Recursos:Universidade Federal de Viçosa (UFV)
Repositório:LOCUS Repositório Institucional da UFV
Idioma:inglês
OAI Identifier:oai:locus.ufv.br:123456789/19784
Acesso em linha:https://doi.org/10.1016/j.micinf.2014.12.009
http://www.locus.ufv.br/handle/123456789/19784
Access Level:Acceso aberto
Palavra-chave:Leishmania amazonensis
E-NTPDase
Adenosine
Nitric oxide
Cytokines
Descrição
Resumo:Leishmania amazonensis, the causal agent of diffuse cutaneous leishmaniasis, is known for its ability to modulate the host immune response. Because a relationship between ectonucleotidase activity and the ability of Leishmania to generate injury in C57BL/6 mice has been demonstrated, in this study we evaluated the involvement of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) activity of L. amazonensis in the process of infection of J774-macrophages. Our results show that high-activity parasites show increased survival rate in LPS/IFN-γ-activated cells, by inhibiting the host-cell NO production. Conversely, inhibition of E-NTPDase activity reduces the parasite survival rates, an effect associated with increased macrophage NO production. E-NTPDase activity generates substrate for the production of extracellular adenosine, which binds to A2B receptors and reduces IL-12 and TNF-α produced by activated macrophages, thus inhibiting NO production. These results indicate that E-NTPDase activity is important for survival of L. amazonensis within macrophages, showing the role of the enzyme in modulating macrophage response and lower NO production, which ultimately favors infection. Our results point to a new mechanism of L. amazonensis infection that may pave the way for the development of new treatments for this neglected disease.