Production and Evaluation of a Novel Multi-Epitope Bivalent Vaccine Against Echinococcus Multilocaularis Metacestode

Alveolar Echinococcosis is a globally widespread zoonotic disease caused by the larval stage of Echinococcus multilocularis (Em) and is seriously harmful to human health. In our previous studies, we found that Em-EMY162 had good prophylactic and therapeutic effects against Em infection and the dominant epitopes of Em-EMY162 and Em-TSP3 were also identified. In this study, a multi-epitope vaccine LTB-ETBM targeting both Em-EMY162 and Em-TSP3 was designed and constructed, and then the immunogenicity and protective efficacy were evaluated in Em infected mice. The results showed that LTB-ETBM could induce high levels of specific IgG against Em-EMY162 and Em-TSP3 and a mixed Th1/Th2 lymphocyte response to LTB-ETBM. Moreover, the LTB-ETBM significantly inhibited the formation of cysts in mice challenged with 1000 Em protoscoleces. In a therapeutic mouse model injected intraperitoneally with 1000 protoscoleces, vaccination with LTB-ETBM using either Freund's or CpG as an adjuvant significantly decreased the growth of protoscoleces and the formation of cysts. LTB-ETBM may be efficacious for use as a prophylactic or therapeutic agent against Em infection.