Multiple Overlapping Epitopes in the Repetitive Unit of the Shed Acute-Phase Antigen from Trypanosoma cruzi Enhance Its Immunogenic Properties

The repetitive shed acute-phase antigen (SAPA) from Trypanosoma cruzi was thoroughly mapped by SPOT peptides and phage display strategies, showing that a single SAPA repeat is composed of multiple overlapping B-cell epitopes. We propose that this intricate antigenic structure constitutes an alternative device to repetitiveness in order to improve its immunogenicity.