Immunogenicity of peptide-based vaccine composed of epitopes from Echinococcus granulosus rEg.P29.

Echinococcus granulosus is one of the main causes of economic loss in the livestock industry because of its food-borne transmission. Cutting off the transmission route is a valid prevention method, and vaccines are the most effective means of controlling and eliminating infectious diseases. However, no human-related vaccine has been yet marketed. As a genetic engineering vaccine, recombinant protein P29 of E. granulosus (rEg.P29) could provide protection against deadly challenges. In this study, we generated peptide vaccines (rEg.P29(T) , rEg.P29(B) , and rEg.P29(T+B) ) based on rEg.P29 and an immunized model was established by subcutaneous immunization. Further evaluation showed that peptide vaccine immunization in mice induced T helper type 1 (Th1)-mediated cellular immune responses, leading to high levels of rEg.P29 or rEg.P29(B) -specific antibodies. In addition, rEg.P29(T+B) immunization can induce a higher antibody and cytokine production level than single-epitope vaccines, and immune memory is also longer. Collectively, these results suggest that rEg.P29(T+B) has the potential to be developed as an efficient subunit vaccine for use in areas where E. granulosus is endemic.