The Ebola virus (EBOV) glycoprotein (GP) can be recognized by neutralizing antibodies (NAbs) and is the main target for vaccine design. We first investigated the contribution of the stalk and the heptad repeat 1-C (HR1C) region to GP metastability. Specific stalk and HR1C modifications in a mucin-deleted form (GPΔmuc) increased trimer yield, while alteration of HR1C exerted a more complex effect on thermostability. Crystal structures were determined to validate these rationally designed GPΔmuc trimers in their unliganded state. We then displayed a modified GPΔmuc trimer on engineered nanoparticles with encapsulated locking domains (LD) and a cluster of helper T-cell epitopes. In mice and rabbits, GP trimers and nanoparticles elicited cross-ebolavirus NAbs as well as non-NAbs that enhance in-vitro infection. Next-generation sequencing (NGS) revealed B-cell profiles that are specific to vaccine platforms. This study provides insight into GP metastability and paves the way for development of an effective, pan-ebolavirus nanoparticle vaccine.
TEASER We rationally redesigned the EBOV glycoprotein and engineered single-component multilayered nanoparticles as vaccine candidates