Theileria parva candidate vaccine antigens recognized by immune bovine cytotoxic T lymphocytes

Proc Natl Acad Sci U S A. 2006 Feb 28;103(9):3286-91. doi: 10.1073/pnas.0511273103. Epub 2006 Feb 21.

Abstract

East Coast fever, caused by the tick-borne intracellular apicomplexan parasite Theileria parva, is a highly fatal lymphoproliferative disease of cattle. The pathogenic schizont-induced lymphocyte transformation is a unique cancer-like condition that is reversible with parasite removal. Schizont-infected cell-directed CD8(+) cytotoxic T lymphocytes (CTL) constitute the dominant protective bovine immune response after a single exposure to infection. However, the schizont antigens targeted by T. parva-specific CTL are undefined. Here we show the identification of five candidate vaccine antigens that are the targets of MHC class I-restricted CD8(+) CTL from immune cattle. CD8(+) T cell responses to these antigens were boosted in T. parva-immune cattle resolving a challenge infection and, when used to immunize naïve cattle, induced CTL responses that significantly correlated with survival from a lethal parasite challenge. These data provide a basis for developing a CTL-targeted anti-East Coast fever subunit vaccine. In addition, orthologs of these antigens may be vaccine targets for other apicomplexan parasites.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Protozoan / immunology*
  • Cattle
  • Cell Line
  • Protozoan Vaccines / immunology*
  • T-Lymphocytes, Cytotoxic / immunology*
  • Theileria parva / immunology*
  • Theileriasis / immunology*
  • Theileriasis / parasitology
  • Theileriasis / pathology
  • Vaccination

Substances

  • Antigens, Protozoan
  • Protozoan Vaccines