Development of T cell antigen-based human coronavirus vaccinesagainst nAb-escaping SARS-CoV-2 variants

针对逃逸中和抗体的新冠突变体开发基于T细胞抗原的人类冠状病毒疫苗

Currently approved vaccines have been successful in preventing the severity of COVID-19 and hospitalization. These vaccines primarily induce humoral immune responses;however, highly transmissible and mutated variants, such as the Omicron variant, weaken the neutralization potential of the vaccines, thus,raising serious concerns about their efficacy. Additionally, while neutralizing antibodies(nAbs) tend to wane more rapidly than cell-mediated immunity, long-lasting T cells typically prevent severe viral illness by directly killing infected cells or aiding other immune cells. Importantly, T cells are more cross-reactive than antibodies, thus, highly mutated variants are less likely to escape lasting broadly cross-reactive T cell immunity. Therefore, T cell antigen-based human coronavirus(HCoV) vaccines with the potential to serve as a supplementary weapon to combat emerging SARS-CoV-2 variants with resistance to n Abs are urgently needed. Alternatively, T cell antigens could also be included in B cell antigen-based vaccines to strengthen vaccine efficacy. This review summarizes recent advancements in research and development of vaccines containing T cell antigens or both T and B cell antigens derived from proteins of SARS-CoV-2 variants and/or other HCo Vs based on different vaccine platforms.