Trans-sialidase overcome many antigens to be used as a vaccine candidate against Trypanosoma cruzi

BONTEMPI IVAN; FREITAS PEDRO; POATO ALEXIA; VICCO MIGUEL; RODELES LUZ; PROCHETTO ESTEFANIA; CABRERA GABRIEL; BELUZZO BRUNO; ARIAS DIEGO; RACCA ANDREA; GUERRERO SERGIO; MARCIPAR IVÁN

IMMUNOTHERAPY

FUTURE MEDICINE LTD

Lugar: Londres; Año: 2017

1750-743X

The protective performances of seven recombinant antigens formulated with Freund´s Adjuvant were compared in the same murine -T. cruzi infection model. TS, CZ, Tc3 and CPX groups presented lower parasitemia and higher survival rates compared to the FRA, Tc6, TXN and controls groups. Before T. cruzi challenge, the humoral evaluation showed that sera from all groups increased the levels of total specific IgG antibodies after immunization, excepting for the Tc6-vaccinated group that turned out to be very weakly immunogenic. Evaluations of the ratio IgG2a/IgG1 showed that the TS, CZ, Tc3 and CPX groups had ratios compatible with a TH 1 profile. CZ, TS, Tc3 and CPX immunogens formulated with the ISCOMATRIX adjuvant, triggered high levels of IgG antibodies and Delayed Type hipersensibility responses to the each respective antigen. After T. cruzi challenge to the groups formulated with IMX, a significant decrease ofparasitemia was observed in the case of the TS-IMX and CZ-IMX as compared to the controls groups (P < 0.05). The survivals rates were of 100% and 80% for the TS and CZ respectively, being the difference significant only for the TS-IMX in relation to the control group (P < 0.05). Based on the obtained results, we conclude that the best vaccine 378 candidate that protected against T. cruzi infection is the TS enzyme formulated with the adjuvant IMX.