Primary evaluation of immune responses in mice after a single mRNA immunization with Echinococcus granulosus Eg95 and Coenurus cerebralis TM16.

Echinococcus granulosus and Taenia multiceps cause zoonotic cystic diseases. Studies have shown that Eg95 from E. granulosus is highly conserved, exhibits excellent immunogenicity, and serves as a critical candidate antigen. In recent years, the TM16 recombinant protein antigen has been one of the most studied antigens for preventing C. cerebralis and demonstrates optimal experimental immunogenicity. This study developed both recombinant protein and mRNA-LNP vaccines targeting the Eg95 and TM16 antigens. Immunization of BALB/c mice showed that both vaccines significantly increased specific antibody levels (IgG, IgG1, IgG2a) and cytokines (IFN-γ, IL-4) (P < 0.001), inducing a predominant Th1-type immune response. The mRNA-LNP vaccine demonstrated superior efficacy in enhancing IgG2a levels and CD8+ T cell responses compared to the protein vaccine. These results indicate strong immunogenicity and support further evaluation of the Eg95-TM16 mRNA-LNP vaccine in intermediate hosts like sheep and goats.