Accomplishing the genotype-specific serodiagnosis of single and dual Trypanosoma cruzi infections by flow cytometry Chagas-Flow ATE-IgG2a

PLoS Negl Trop Dis. 2018 Feb 20;12(2):e0006140. doi: 10.1371/journal.pntd.0006140. eCollection 2018 Feb.

Abstract

The methods currently available for genotype-specific diagnosis of T. cruzi infection still present relevant limitations, especially to identify mixed infection. In the present investigation, we have evaluated the performance of Chagas-Flow ATE-IgG2a test for early and late differential diagnosis of single and dual genotype-specific T. cruzi infections. Serum samples from Swiss mice at early and late stages of T. cruzi infection were assayed in parallel batches for genotype-specific diagnosis of single (TcI, TcVI or TcII) and dual (TcI+TcVI, TcVI+TcII or TcII+TcI) infections. The intrinsic reactivity to TcI, TcVI and TcII target antigens, including amastigote (AI/AVI/AII), trypomastigote-(TI/TVI/TII) and epimastigote (EI/EVI/EII), at specific reverse of serum dilutions (500 to 64,000), was employed to provide reliable decision-trees for "early" vs "late", "single vs "dual" and "genotype-specific" serology. The results demonstrated that selective set of attributes "EII 500/EI 2,000/AII 500" were able to provide high-quality accuracy (81%) to segregate early and late stages of T. cruzi infection. The sets "TI 2,000/AI 1,000/EII 1,000" and "TI 8,000/AII 32,000" presented expressive scores to discriminate single from dual T. cruzi infections at early (85%) and late stages (84%), respectively. Moreover, the attributes "TI 4,000/TVI 500/TII 1,000", "TI 16,000/EI 2,000/EII 2,000/AI 500/TVI 500" showed good performance for genotype-specific diagnosis at early stage of single (72%) and dual (80%) T. cruzi infections, respectively. In addition, the attributes "TI 4,000/AII 1,000/EVI 1,000", "TI 64,000/AVI 500/AI 2,000/AII 1,000/EII 4,000" showed moderate performance for genotype-specific diagnosis at late stage of single (69%) and dual (76%) T. cruzi infections, respectively. The sets of decision-trees were assembled to construct a sequential algorithm with expressive accuracy (81%) for serological diagnosis of T. cruzi infection. These findings engender new perspectives for the application of Chagas-Flow ATE-IgG2a method for genotype-specific diagnosis in humans, with relevant contributions for epidemiological surveys as well as clinical and post-therapeutic monitoring of Chagas disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Protozoan / genetics
  • Antigens, Protozoan / immunology
  • Chagas Disease / diagnosis*
  • Chagas Disease / immunology*
  • Disease Models, Animal
  • Female
  • Flow Cytometry / methods*
  • Genotype*
  • Humans
  • Immunoglobulin G / blood*
  • Mice
  • Neuraminidase / immunology
  • Protozoan Proteins / immunology
  • Serologic Tests / methods*
  • Trypanosoma cruzi / genetics*
  • Trypanosoma cruzi / immunology*
  • Trypanosoma cruzi / pathogenicity

Substances

  • Antigens, Protozoan
  • Immunoglobulin G
  • Protozoan Proteins
  • Neuraminidase

Grants and funding

This work was supported by European Community`s Seventh Framework Program No. 602773- Project KINDRED). Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenadoria de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Instituto René Rachou and Universidade Federal de Ouro Preto. GDA received PhD research fellowship form CAPES. OAM-F and AT-C received financial support from CNPq PQ Fellowship program. FFdA thanks PNPD/CAPES fellowship program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.