Introduction: Trypanosoma cruzi is the causative agent of Chagas disease. During infection in mammalian hosts, two main forms of the parasite are observed: trypomastigotes and amastigotes. During differentiation, each stage of the parasite expresses a pattern of proteins specific to each phase-proteins which are responsible for the cell's morphological, biochemical and biological properties. These properties ultimately govern the infectivity, virulence and survival of the parasite.
Objective: A differential expression analysis was conducted to compare trypomastigote and amastigote stages of T. cruzi I isolate, and to identify proteins differentially expressed by means of mass spectrometry.
Materials and methods: A T. cruzi clone of the strain MHOM/07/338 was used to analyze the differential expression between trypomastigote stages of a T. cruzi isolate, using two-dimensional electrophoresis and identification of differentially expressed proteins by mass spectrometry. The protein profiles of the stages of the parasite were obtained by two-dimensional gel electrophoresis and visualized in gels dyed with Coomassie blue. The images were analyzed with PDQuest software and the differential expression of the proteins was identified by MALDI TOF or LC MS/MS.
Results: The two-dimensional gels revealed an average of 325 protein spots in each stage. The comparative analyses detected 21 spots that were over expressed in the trypomastigote stage and 30 in the amastigote stage. Sixteen of the over expressed proteins were selected for identification by mass spectrometry and classified in several functional categories. Mass spectrophotometry determined that the proteins were associated mainly with glucolytic metabolism and assembly of the cytoskeleton constituents.
Conclusions: The differential expression between trypomastigote and amastigote stages consisted of proteins specific to T. cruzi and are potential targets for the design of treatment drugs.