Deep immunophenotyping of systemic immunological changes in non-human primates after administration of a VSV-vectored Nipah vaccine 4331

Abstract Description Nipah virus (NiV) is a highly pathogenic emerging viral zoonotic disease which causes severe respiratory disease and febrile encephalitis in humans. The virus is associated with a 40-70% case fatality rate and has the potential for aerosol transmission. There are currently no licensed vaccines or treatments available to combat disease. Recombinant vesicular stomatitis virus-vectored vaccines are safe and rapidly efficacious with a single dose, which makes them ideal for deployment during outbreaks and in remote areas as seen with the success of Ervebo® during the 2013-2016 Zaire ebolavirus epidemic in West Africa. In this study, we evaluated the minimum dose needed to provide protective efficacy for a single dose of rVSVΔG-NiV-G vaccine after intratracheal/intranasal or mucosal atomization device challenge with NiV. Notably, some vaccinated animals receiving low doses in both groups succumbed to disease, enabling us to elucidate systemic mechanisms of protection in survivors. We employed advanced techniques including bead-based immunoassays and ultra-high-parameter spectral flow cytometry to profile immune cell subsets including functional and intracellular targets. This work highlights the VSV-based immune mechanisms required to protect against high-risk zoonotic henipaviruses. Funding Sources This work was funded by US Army Medical Research Acquisition Activity contract W81XWH1910028 to TWG Topic Categories Vaccines and Immunotherapy (VAC)