Abstract
Safe and effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants are the best approach to successfully combat the COVID-19 pandemic. The receptor-binding domain (RBD) of the viral spike protein is a major target to develop candidate vaccines. α-Galactosylceramide (αGalCer), a potent invariant natural killer T cell (iNKT) agonist, was site-specifically conjugated to the N -terminus of the RBD to form an adjuvant-protein conjugate, which was anchored on the liposome surface. This is the first time that an iNKT cell agonist was conjugated to the protein antigen. Compared to the unconjugated RBD/αGalCer mixture, the αGalCer-RBD conjugate induced significantly stronger humoral and cellular responses. The conjugate vaccine also showed effective cross-neutralization to all variants of concern (B.1.1.7/alpha, B.1.351/beta, P.1/gamma, B.1.617.2/delta, and B.1.1.529/omicron). These results suggest that the self-adjuvanting αGalCer-RBD has great potential to be an effective COVID-19 vaccine candidate, and this strategy might be useful for designing various subunit vaccines.
【초록키워드】 SARS-CoV-2, Vaccine, coronavirus, COVID-19 vaccine, Vaccines, neutralization, COVID-19 pandemic, variant, variants of concern, severe acute respiratory syndrome Coronavirus, omicron, Spike protein, Antigen, Protein, T cell, Viral, Receptor-binding domain, RBD, cross-neutralization, Alpha, Beta, B.1.1.529, respiratory, Liposome, subunit vaccines, humoral, Cellular responses, best, natural killer, viral spike protein, acute respiratory syndrome, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, domain, Effective vaccines, agonist, approach, effective, Cell, develop, significantly, the RBD, effective vaccine, iNKT, 【제목키워드】 SARS-CoV-2, concern, potent, lipoprotein, conjugate,