Identification of Theileria lestoquardi Antigens Recognized by CD8+ T Cells

PLoS One. 2016 Sep 9;11(9):e0162571. doi: 10.1371/journal.pone.0162571. eCollection 2016.

Abstract

As part of an international effort to develop vaccines for Theileria lestoquardi, we undertook a limited screen to test T. lestoquardi orthologues of antigens recognised by CD8+ T lymphocyte responses against T. annulata and T. parva in cattle. Five MHC defined sheep were immunized by live T. lestoquardi infection and their CD8+ T lymphocyte responses determined. Thirteen T. lestoquardi orthologues of T. parva and T. annulata genes, previously shown to be targets of CD8+ T lymphocyte responses of immune cattle, were expressed in autologous fibroblasts and screened for T cell recognition using an IFNγ assay. Genes encoding T. lestoquardi antigens Tl8 (putative cysteine proteinase, 349 aa) or Tl9 (hypothetical secreted protein, 293 aa) were recognise by T cells from one animal that displayed a unique MHC class I genotype. Antigenic 9-mer peptide epitopes of Tl8 and Tl9 were identified through peptide scans using CD8+ T cells from the responding animal. These experiments identify the first T. lestoquardi antigens recognised by CD8+ T cell responses linked to specific MHC class I alleles.

MeSH terms

  • Animals
  • Antigens, Protozoan / immunology*
  • CD8-Positive T-Lymphocytes
  • Cattle
  • Genes, MHC Class I / genetics
  • Genes, MHC Class I / physiology
  • Sheep
  • Theileria / immunology*
  • Theileria / pathogenicity
  • Theileriasis / immunology*
  • Vaccines / immunology

Substances

  • Antigens, Protozoan
  • Vaccines

Grants and funding

The work was funded by the EU Seventh Framework Programme for Research (FP7), grant number 245145—PIROVAC, http://www.theileria.org/pirovac/. The funder had no role in study design, data collection and interpretation, or the decision to submit work for publication.