Results
The antigenic specificity of CTL from MHC class I-matched cattle vaccinated with the Muguga cocktail were different. Three cattle of MHC class I haplotype A18, one A18/A19 and two haploidentical (A18v/A12) animals, showed differential recognition of autologous cells infected with a panel of T. parva isolates. This could have implications in the field where certain strains could break through the vaccine. Furthermore, neither of the haploidentical cattle recognized the CTL epitope (Tp1214-224), presented by the A18 haplotype, in contrast to the third animal, showing differences in immunodominance in animals of the same haplotype A18. This suggests that the CTL specificities following immunization with the Muguga cocktail can vary even between haploidentical individuals and that some parasite strains may break through immunity generated by the Muguga cocktail.