Titre:	Leishmania infantum and Leishmania braziliensis : differences and similarities to evade the innate immune system
Auteur(s):	Falcão, Sarah de Athayde Couto Jaramillo, Tatiana María Giraldo Ferreira, Luciana G. Bernardes, Daniela M. Santana, Jaime Martins de Favali, Cecilia Beatriz Fiuza
Assunto::	Leishmaniose visceral Leishmania Células dendríticas Parasito
Date de publication:	3-aoû-2016
Editeur:	Frontiers
Référence bibliographique:	FALCÃO, Sarah de Athayde Couto et al. Leishmania infantum and Leishmania braziliensis: differences and similarities to evade the innate immune system. Frontiers in Immunology, v. 7, Article 287, 3 ago. 2016. Disponível em: <http://journal.frontiersin.org/article/10.3389/fimmu.2016.00287/full>. Acesso em: 21 jun. 2017. doi: http://journal.frontiersin.org/article/10.3389/fimmu.2016.00287/full.
Abstract:	Visceral leishmaniasis is a severe form of the disease, caused by Leishmania infantum in the New World. Patients present an anergic immune response that favors parasite establishment and spreading through tissues like bone marrow and liver. On the other hand, Leishmania braziliensis causes localized cutaneous lesions, which can be self-healing in some individuals. Interactions between host and parasite are essential to understand disease pathogenesis and progression. In this context, dendritic cells (DCs) act as essential bridges that connect innate and adaptive immune responses. In this way, the aim of this study was to compare the effects of these two Leishmania species, in some aspects of human DCs’ biology for better understanding of the evasion mechanisms of Leishmania from host innate immune response. To do so, DCs were obtained from monocytes from whole peripheral blood of healthy volunteer donors and from those infected with L. infantum or L. braziliensis for 24 h. We observed similar rates of infection (around 40%) as well as parasite burden for both Leishmania species. Concerning surface molecules, we observed that both parasites induced CD86 expres-sion when DCs were infected for 24 h. On the other hand, we detected a lower surface expression of CD209 in the presence of both L. braziliensis and L. infantum, but only the last one promoted the survival of DCs after 24 h. Therefore, DCs infected by both Leishmania species showed a higher expression of CD86 and a decrease of CD209 expression, suggesting that both enter DCs through CD209 molecule. However, only L. infantum had the ability to inhibit DC apoptotic death, as an evasion mechanism that enables its spreading to organs like bone marrow and liver. Lastly, L. braziliensis was more silent parasite, once it did not inhibit DC apoptosis in our in vitro model.
Licença::	Copyright © 2016 Falcão, Jaramillo, Ferreira, Bernardes, Santana and Favali. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
DOI:	https://dx.doi.org/10.3389/fimmu.2016.00287
Collection(s) :	Artigos publicados em periódicos e afins

Tous les documents dans DSpace sont protégés par copyright, avec tous droits réservés.