Identification of multiple HLA-A*0201-restricted cruzipain and FL-160 CD8+ epitopes recognized by T cells from chronically Trypanosoma cruzi-infected patients

Microbes Infect. 2005 Apr;7(4):688-97. doi: 10.1016/j.micinf.2005.01.001. Epub 2005 Mar 21.

Abstract

Chronic Chagas disease occurs in 16 million individuals chronically infected by the protozoan Trypanosoma cruzi in Latin America, and may lead to a dilated cardiomyopathy in 10-30% of patients. A vigorous cellular immune response holds parasitism in check. However, up to now, few T. cruzi proteins have been shown to be recognized by CD8+ T cells from Chagas disease patients. In this study, we designed 94 peptides derived from T. cruzi proteins cruzipain and FL-160, predicted to bind to HLA-A2 molcules. After in vitro binding assays to HLA-A*0201, 26 peptides were selected, and their recognition by PBMC from Chagas disease patients was tested with the IFN-gamma ELISPOT assay. All 26 peptides were recognized by PBMC from at least one patient. Furthermore, a tetrameric HLA-A*0201 complex built with the cruzipain 60-68 peptide that was frequently recognized in the periphery also bound to CD8+ T cells from a heart-infiltrating T cell line obtained from a single patient with Chagas disease cardiomyopathy. Thus, our results suggest that the recognition of CD8+ T cell epitopes in cruzipain and FL-160 may have a pathogenic or protective role in chronic Chagas disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antigens, Protozoan / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Cell Line
  • Chagas Disease / immunology
  • Chagas Disease / parasitology
  • Chronic Disease
  • Cysteine Endopeptidases / immunology*
  • Epitope Mapping*
  • Epitopes, T-Lymphocyte / immunology*
  • HLA-A Antigens / immunology*
  • HLA-A2 Antigen
  • Humans
  • Interferon-gamma / biosynthesis
  • Leukocytes, Mononuclear / immunology
  • Molecular Sequence Data
  • Peptides / chemistry
  • Peptides / immunology
  • Protozoan Proteins
  • Trypanosoma cruzi / immunology*

Substances

  • Antigens, Protozoan
  • Epitopes, T-Lymphocyte
  • HLA-A Antigens
  • HLA-A*02:01 antigen
  • HLA-A2 Antigen
  • Peptides
  • Protozoan Proteins
  • FL-160 antigen, Trypanosoma cruzi
  • Interferon-gamma
  • Cysteine Endopeptidases
  • cruzipain