The ability to maintain T.parva-infected cell lines as rapidly proliferating cells in vitro that express high levels of both MHCI and MHCII, makes this a particularly amenable system in which to apply MHCp elution analysis. Furthermore, the ability of T. parva-infected cells to recall antigen-specific T-cells without the need for supplementary APCs indicates that the peptides presented by T. parva are those that stimulate T-cell responses. We have utilised the repertoire of bovine derived peptides from MHCp elution studies conducted on T. parva-infected cells to define the peptide binding motifs of a variety of BoLA-MHCI and BoLA-DR molecules and facilitated the development of novel more accurate peptide binding prediction algorithms.