Development of Nipah virus mRNA vaccine for pandemic preparedness

Nipah virus (NiV) is a highly pathogenic zoonotic virus associated with a high case fatality rate and human-to-human transmission, and it is listed as a priority pathogen by the World Health Organization (WHO) due to the lack of approved therapeutics or vaccines. NiV is classified as a biosafety level 4 (BSL-4) pathogen, which severely limits experimental studies in the absence of specialized containment facilities. Therefore, the establishment of pseudovirus-based surrogate models is essential for NiV vaccine research.

In this study, single-antigen mRNA-lipid nanoparticle (mRNA-LNP) vaccines encoding the Nipah virus fusion protein (NiV-F) and attachment protein (NiV-G) were designed and evaluated using a co-administration strategy of independently formulated single-antigen mRNA-LNPs. A Vesicular stomatitis virus (VSV)-based NiV pseudovirus system was established and applied to assess neutralizing antibody responses in a mouse model.

The synthesized mRNA-LNP vaccines exhibited high purity and relatively consistent physicochemical properties, indicating uniform formulation characteristics. The VSV-based NiV pseudovirus showed a robust infection signal compared to background controls, and optimization of the purification process effectively reduced non-specific background, enabling reliable evaluation of in vitro neutralizing activity induced by vaccination. Coadministration of the NiV-F and NiV-G mRNA-LNP vaccines induced detectable antigen-binding antibody responses against both NiV-F and NiV-G antigens. Consistently, pseudovirus-based neutralization assays (PBNA) demonstrated detectable neutralizing activity in sera collected at week 4 post-immunization.

This study provides a foundation for future NiV mRNA-LNP vaccine development and presents a flexible vaccine design approach based on co-administration of independently formulated single-antigen mRNA-LNPs in which mixed administration of single-antigen mRNA-LNPs provides a flexible framework for independently modulating antigen composition and enabling antigen-specific immune responses. These findings provide a basis for future studies exploring diverse antigen combinations in NiV vaccine research.