An RBD virus-like particle vaccine for SARS-CoV-2 induces cross-variant antibody responses in mice and macaques
Yuanyuan Li, Yanan Zhang, Yu Zhou, Yan Li, Jiao Xu, Yuanbao Ai, Lei Xu, Xiuli Xiao, Bo Zhang, Jing Jin, Bo Zhang, Jing Jin
Abstract
Since early 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally infecting over 500 million people and causing over 6 million deaths. The massive worldwide immunisation programmes and the arising clinical trial data present a unique opportunity to compare the vaccines and various delivery platforms (i.e. viral vector platform, mRNA platform and virus-like particle platform). As reviewed from the published clinical data, 1 it is evident that the mRNA vaccines (mRNA-1273 from Moderna, BNT162b2 from Pfizer) and subunit protein/adjuvant vaccine (NVAX-CoV2373 from Novavax) were able to induce an average 2–4 fold greater neutralizing antibody (nAb) titer as compared to the human convalescent serum (HCS) control. On the other hand, the viral vectored vaccines (Ad26.COV2.S from Johnson & Johnson, ChAdOx1 nCoV-19 from AstraZeneca) and the inactivated vaccine (CoronaVac from Sinovac) induced less nAb than the HCS. Interestingly, CoVLP from Medicago, which uses a plant-based virus-like particle (VLP) platform technology, was able to induce a >10-fold increase in the nAb response as compared to HCS; 2 suggesting VLP vaccine or arrayed antigen delivery is highly immunogenic.