Experimental infection and therapeutic treatment
For cytotoxicity assay, BALB/c mice from 7-8 weeks old were infected with 500 blood trypomastigotes of T. cruzi (H1 strain) by intraperitoneal injection. Consecutively, mice were injected intramuscularly with the recombinant antigen combination vaccine (n=10). The vaccine was comprised by 10 μg of each recombinant antigen (TSA-1-C4 plus Tc24-C4) and 5 μg of E6020-SE. Additional groups of mice received TSA-1-C4+E6020-SE (n=10), Tc24-C4+E6020-SE (n=10) or saline solution (n=10) as controls. We also added a control group of non-infected and non-treated mice (n=10). One and two weeks after (days 7 and 14 p.i.)., boost vaccination was given with the same formulation described. At day 50 p.i., all mice were euthanized using ketamine/xylazine-induced deep anaesthesia followed by cervical dislocation, and spleens were collected.