Volume 7 Issue 8, Aug 2022

ISSN: 2095-9907 

EISSN: 2059-23635 

2023 impact factor 40.8 

 (Clarivate Analytics, 2024)
Volume 7 Issue 8, Aug 2022:
Article
Comparative characterization of antibody responses induced by Ad5-vectored spike proteins of emerging SARS-CoV-2 VOCs
Busen Wang  ORCID: orcid.org/0000-0001-9041-1919,Jinghan Xu,Shipo Wu,Zhe Zhang,Zhenghao Zhao,Jun Zhang  ORCID: orcid.org/0000-0002-9650-112X,Ling Fu,Xiaodong Zai,Yudong Wang,Guanying Zhang,ZhengShan Chen,Yi Chen,Hancong Sun,Xiaohong Song,Jinlong Zhang,Lianhui Zhu,Lihua Hou &…Wei Chen  ORCID: orcid.org/0000-0001-5805-2469 
Highly divergent SARS-CoV-2 variants have continuously emerged and spread around the world, and updated vaccines and innovative vaccination strategies are urgently needed to address the global SARS-COV2 pandemic. Here, we established a series of Ad5-vectored SARS-CoV-2 variant vaccines encoding multiple spike proteins derived from the Alpha, Beta, Gamma, Epsilon, Kappa, Delta and Omicron lineages and analyzed the antibody immune responses induced by single-dose and prime-boost vaccination strategies against emerging SARS-CoV-2 variants of concern (VOCs). Single-dose vaccination with SARS-CoV-2 variant vaccines tended to elicit the optimal self-matched neutralizing effects, and Ad5-B.1.351 produced more broad-spectrum cross-neutralizing antibodies against diverse variants. In contrast, prime-boost vaccination further strengthened and broadened the neutralizing antibody responses against highly divergent SARS-CoV-2 variants. The heterologous administration of Ad5-B.1.617.2 and Ad5-B.1.429 to Ad5-WT-primed mice resulted in superior antibody responses against most VOCs. In particular, the Omicron spike could only stimulate self-matched neutralizing antibodies with infrequent cross-reactivities to other variants used in single-dose vaccination strategies; moreover, with prime-boost regimens, this vaccine elicited an optimal specific neutralizing antibody response to Omicron, and prompted cross-antibody responses against other VOCs that were very similar to those obtained with Ad5-WT booster. Overall, this study delineated the unique characteristics of antibody responses to the SARS-CoV-2 VOC spikes with the single-dose or prime-boost vaccination strategies and provided insight into the vaccine development of next SARS-CoV-2 VOCs.