Purified excreted-secreted antigens from Trypanosoma cruzi trypomastigotes as tools for diagnosis of Chagas' disease

J Clin Microbiol. 2006 Feb;44(2):291-6. doi: 10.1128/JCM.44.2.291-296.2006.


There is currently no "gold standard" test for the diagnosis of late-stage Chagas' disease. As a result, protection of the blood supply in areas where Chagas' disease is endemic remains problematic. A panel of 709 serum samples from subjects with confirmed Chagas' disease (n = 195), healthy controls (n = 400), and patients with other parasitic diseases (n = 114) was used to assess enzyme-linked immunosorbent assays (ELISAs) based on a concentrated extract of excretory-secretory antigens from either Brazil or Tulahuen strain Trypanosoma cruzi trypomastigotes (total trypomastigote excretory-secretory antigens [TESAs]). The total TESA-based assays had excellent overall sensitivity (100%) and specificity (>94%), except for cross-reactivity with Leishmania-infected sera. In an attempt to increase the specificity of the assay, immunoaffinity chromatography was used to purify the TESA proteins (TESA(IA) proteins). By Western blotting, a series of polypeptide bands with molecular masses ranging from 60 to 220 kDa were recognized by pooled sera positive for Chagas' disease. An ELISA based on TESA(IA) proteins had a slightly lower sensitivity (98.6%) but an improved specificity (100%) compared to the sensitivity and specificity of the total TESA protein-based ELISAs. A 60-kDa polypeptide was identified as a major contributor to the cross-reactivity with Leishmania. These data suggest the need for field validation studies of TESA- and TESA(IA)-based assays in regions where Chagas' disease is endemic.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Protozoan / blood*
  • Antigens, Protozoan / immunology*
  • Antigens, Protozoan / isolation & purification*
  • Antigens, Protozoan / metabolism
  • Chagas Disease / diagnosis*
  • Chagas Disease / immunology
  • Chromatography, Affinity / methods
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Sensitivity and Specificity
  • Serologic Tests
  • Trypanosoma cruzi / immunology*


  • Antibodies, Protozoan
  • Antigens, Protozoan