Synthetic peptides induce antibodies in sheep against Taenia ovis

Two peptides corresponding to putative protective regions located at the N- and C-termini of the host-protective T. ovis recombinant antigen, 45W, were synthesized. Antibodies raised against 45W and 45WB/X, a truncated form of 45W, were found to react strongly with the N-terminal peptide. When sheep were immunised with each peptide alone, the N-terminal peptide was found to be highly immunogenic, whereas the C-terminal peptide required conjugation to a carrier protein to be immunogenic. Both these immunogens elicited antibodies that cross-reacted with the parent protein; however, only antibodies directed toward the N-terminal peptide were able to bind antigens from the T. ovis oncosphere. Significant protection against challenge infection was not provided by any of the peptide immunogens used.