Galectina-3 desempenha um papel protetivo na infecção por Leishmania (Leishmania) amazonensis

Abstract

Leishmania (L.) amazonensis is one of the species responsible for cutaneous leishmaniasis in South America. After entering the vertebrate host, L. (L.) amazonensis invades mainly neutrophils, macrophages and dendritic cells. These cells have high levels of galectin-3 expression. Studies show that gal-3 can act as pattern recognition receptor (PRR) and pathogen-associated molecular pattern (PAMP), performing a series of functions in several microorganisms infections. However, the role of this protein in the context of L. (L.) amazonensis infection is unknown. Here we demonstrate, through in vitro and in vivo assays, the importance of gal-3 in parasite infection. Our data showed that in peritoneal macrophages of L. (L.) amazonensis infected C57BL/6 galectin-3 knockout (gal-3 KO) mice, there was a higher number of infected cells and parasites, when compared to WT cells. We also saw that in the absence of gal-3, there was a higher formation of parasitophorous vacuoles, as well as a higher apoptosis and necrosis presence in peritoneal cells of infected mice. In addition, we observed, in vivo, that 8 weeks after L. (L.) amazonensis infection in the footpads, gal-3 KO mice showed higher parasite load and inflammation compared to WT. In this way, we obtained experimental evidence that gal-3 plays an important role in the course of the L. (L.) amazonensis infection.