Effect of Tryptophan in placental explants infection by Trypanosoma cruzi in vitro

MOREIRA ESPINOZA, MARÍA JOSÉ; TRIQUELL, MARÍA FERNANDA; DÍAZ-LUJÁN, CINTIA; PIEGARI, MARIANA; MAZZUDULLI, GINA; MEZZANO, LUCIANA; FRETES, RICARDO E

Mar del Plata

Congreso; X Congreso de Protozoología y Enfermedades Parasitarias; 2014

Sociedad Argentina de Protozoología

Tryptophan (Trp) catabolism participates in the maternal-fetal tolerance through indoleamine 2,3-dioxigenase (IDO), which is an enzyme strongly expressed in human placenta. IDO limits the infection of mice experimentally infected with Trypanosoma cruzi. Objective: To analyze the effect of Trp in the invasion of human placental chorionic villi by T. cruzi, in-vitro. Methodology: We employed explants of chorionic villi of placentas obtained from normal pregnancies at term (n=4). Women have signed informed consents. Placental explants were treated with different concentrations (5mg, 10mg, 20mg y 40mg) of L-Trp and D-Trp (as control), for 3hs and/or infected for 24hs with 150.000 and 1.000.000 trypomastigotes Tulahuen strain of T. cruzi, then culture media were changed. Placental explants and their respective culture media were analyzed at 72hs using Student t test, ANOVA and correlation analysis (r). Results: All explants were positive to infection by T. cruzi detected by PCR and microscopical analysis, but they have distinct parasite charge (qPCR) with different Trp concentrations. According to western blot and indirect ELISA, IDO modified its expression at 3hs, but there was not significantly differences respect to controls in the subsequent times of culture (p>0,05). Parasite viability was quantified in culture media at 72 hs of cultures with decreased viability respect to controls (p