Abstract:
In the quest for heightened protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
variants, we engineered a prototype vaccine utilizing the plant expression system of Nicotiana benthamiana, to
produce a recombinant SARS-CoV-2 virus-like particle (VLP) vaccine presenting the S-protein from the Beta
(B.1.351) variant of concern (VOC). This innovative vaccine, formulated with either a squalene oil-in-water
emulsion or a synthetic CpG oligodeoxynucleotide adjuvant, demonstrated efficacy in a golden Syrian Hamster
challenge model. The Beta VLP vaccine induced a robust humoral immune response, with serum exhibiting
neutralization not only against SARS-CoV-2 Beta but also cross-neutralizing Delta and Omicron pseudoviruses.
Protective efficacy was demonstrated, evidenced by reduced viral RNA copies and mitigated weight loss and lung
damage compared to controls. This compelling data instills confidence in the creation of a versatile platform for
the local manufacturing of potential pan-sarbecovirus vaccines, against evolving viral threats.
