MTOR INHIBITION IN TRYPANOSOMA CRUZI INFECTED MACROPHAGES PRODUCES INFLAMMATORY MEDIATORS THAT REGULATE ITS SURVIVAL

ROJAS MÁRQUEZ, JD; ANA, Y; STEMPIN, CC; CERBAN FM

Mar del Plata

Congreso; LXIV REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INMUNOLOGÍA; 2016

We have previously shown that Trypanosoma cruzi infection in macrophages (Mo) activates mTOR and its inhibition decreased parasite replication. Besides, in rapamycin (Rap) pre-treated and infected Mo we observed reduced arginase activity and expression compared to control cells. Surprisingly, we also found reduced iNOS activity and expression. Therefore, the aim of this work was to determine alternative mechanisms involved in controlling parasite replication in Rap pre-treated and infected Mo. In this context, we evaluated ROS production. We did not found differences in ROS production after 24h post infection (pi) between Rap or DMSO pre-treated and infected Mo. Also, we evaluated whether indoleamine 2,3-dioxygenase (IDO) enzyme was involved. To do that, we inhibit IDO activity by using 1MT (1-methyl-tryptophan) and we study parasite replication by immunofluorescence (IF). We did not found differences compared to control cells without 1MT and then IDO activity is either not involved in decreasing parasite replication in Rap pre-treated and infected Mo. Consequently, to study possible mediators involved in parasite killing in BMDM from different KO mice (TLR2, TLR4, IFNa-R, Caspase-1, IL-6, TNFa-R and NLRP3), parasite load was evaluated 72h pi by IF. We observed a significant increase in parasite load in Rap pre-treated and infected BMDM from IL-6-KO, TNFa-R-KO and NLRP3-KO mice compared to WT pre-treated and infected control cells for each strain. However, parasite number stands out in BMDM from NLRP3 KO (p