Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Reciprocal cross-protection induced by sporozoite antigens SPAG-1 from Theileria annulata and p67 from Theileria parva.

Abstract

Friesian calves were immunized with a recombinant form of the Theileria annulata major sporozoite surface antigen SPAG-1 or the related T. parva antigen p67, which have previously been shown to induce a degree of homologous protection (they also share sequence homology and are serologically cross-reactive). The vaccine was given in 3 doses at monthly intervals, and 14 days after the last one the calves were challenged with T. annulata or T. parva. The results confirmed that these antigens conferred some protection against homologous species challenge, and also showed that they mutually conferred a degree of cross-species protection, raising the prospect of a common vaccine in the future.