A nanoparticle vaccine targeting glycoprotein D induces immune protection against pseudorabies virus

Pseudorabies virus (PRV) is a highly transmissible zoonotic pathogen that poses a serious threat to the swine industry and presents potential public health risks. In this study, we designed a tetrameric antigen targeting PRV glycoprotein D (gD) and constructed a nanoparticle vaccine by coupling fluorinated polyethylenimine (FPEI) with λ-carrageenan (λ-CGN). Results showed that gD-FPEI-λ-CGN exhibited favorable immunostimulatory in vitro. Comprehensive biosafety evaluations demonstrated that the nanoparticles showed negligible cytotoxicity and no observable histopathological damage in major mouse organs. Neutralization assays revealed that the vaccine prompted high levels of PRV-specific neutralizing antibodies. Furthermore, Enzyme-linked immunosorbent assay (ELISA) results showed that gD-FPEI-λ-CGN induced a Th1-biased cellular immune response in vivo. Upon PRV challenge, mice immunized with gD-FPEI-λ-CGN showed effective protection, resulting in reduced mortality. This study highlights a materials-based nanoparticle platform that integrates antigen multimerization and immune modulation, offering a promising strategy for PRV vaccine development.