Improved proteomic approach for the discovery of potential vaccine targets in Trypanosoma cruzi

摘要

Chagas disease, caused by Trypanosoma cruzi, is a devastating parasitic infection affecting millions of people. Although many efforts have been made for the development of immunotherapies, there is no available vaccine against this deadly infection. One major hurdle for the rational approach to develop a T. cruzi vaccine is the limited information about the proteins produced by different phylogenetic lineages, strains, and stages of the parasite. Here, we have adapted a 1D nanoHPLC system to perform online 2D LC-MS/MS, using the autosampler to inject the eluting salt solutions in the first dimension separation. The application of this methodology for the proteomic analysis of the infective trypomastigote stage of T. cruzi led to the identification of 1,448 non-redundant proteins. Furthermore, about 14% of the identified sequences comprise surface proteins, most of them glycosylphosphatidylinositol (GPI)-anchored and related to parasite pathogenesis. Immunoinformatic analysis revealed thousands of potential peptides with high affinity for major histocompatibility complex (MHC) class I and II presentation. The high diversity of proteins expressed on trypomastigote surface may have many implications for host-cell invasion and immunoevasion mechanisms triggered by the parasite. Finally, we performed a rational approach to filter potential epitopes that could be further tested and validated for development of a Chagas disease vaccine.