Serological tests are preferentially used for the diagnosis of
Chagas' disease (CD) during the chronic phase because of the low
parasitemia and high anti-Trypanosoma cruzi antibody titers. However, the current methods showed several disadvantages, as contradictory or inconclusive results, mainly related to the characteristics of the
antigens used, in general, crude or whole parasites, but also due to
antigen production protocol and the experimental conditions used in serological tests. Thus, better-quality serological assays are urgently needed. Here, we performed a wide immunogenomic screen strategy to identify conserved linear
B-cell epitopes in the predicted
proteome based on genome sequence from T. cruzi strains to will be applied as synthetic
peptides in the serodiagnosis of the chronic CD. Three
B-cell epitopes derived from
mucin-associated
surface protein (
MASP) family, expressed in both infective parasite stages, trypomastigote and amastigotes, conserved in T. cruzi strains, and highly divergent as compared with Leishmania spp.
proteome, were selected for this study. The results demonstrated that synthetic
peptide 2 and a mixture of
peptides (Mix II:
peptides 2 and 3) were able to identify all chronic CD cases, indeterminate or
Chagas cardiomyopathy clinical presentation, and simultaneously able to discriminate
infections caused by Leishmania parasites, with high accuracy (98.37 and 100.00%, respectively) and agreement (kappa index = 0.967 and 1.000, respectively) with direct methods as compared to current diagnostic pipeline performed by reference laboratories in Brazil. This study represents an interesting strategy for the discovery of new
antigens applied to serologic diagnosis of
infectious diseases and for the technological development of platforms for large-scale production of diagnostic tests.