Surface Display of Cholera Toxin B Subunit Recombinant Ghosts Further Enhances Resistance to Infection in Mice.

() is an important zoonotic pathogen that seriously endangers the development of animal husbandry. Vaccination is the most effective approach to preventing infection. We previously reported a recombinant ghost (rECG)-based vaccine that demonstrated outstanding protective efficacy. In this study, we further attempted to fuse the cholera toxin B subunit (CTB), a widely studied potent mucosal immune adjuvant, with macrophage infectivity potentiator (MIP), a candidate antigen of , on the surface of the rECG and explore its protective effect against infection. The MIP fusion protein was highly expressed in the rECGs, and the CTB-modified rECGs significantly induced the activation of mouse bone marrow-derived dendritic cells in vitro. Intranasal immunization with rECGs induced a Th1-biased cellular immune response. Compared to the rECGs without CTB, the CTB-modified rECGs induced higher concentrations of IgA in the serum and vaginal wash solution. Moreover, in a mouse infection model, the CTB-modified rECGs significantly improved the clearance efficiency of and reduced the pathological damage to the uterus. This study demonstrates that incorporating CTB into rECGs significantly enhances the immunogenic potential of the rECG vaccine and can significantly enhance its protective efficacy against a challenge.