An AAV vaccine targeting the RBD of the SARS-CoV-2 S protein induces effective neutralizing antibody titers in mice and canines

• Published in: Vaccine 2022-02, Vol.40 (9), p.1208-1212
• Main Authors: Liu, Fei, Feng, Canbin, Xu, Shiqi, Wu, Qiang, Tang, Jian, Chen, Yan, Xu, Ruisheng, Chen, Fuliang, Gao, Ni, Xu, Zhengzheng, Gu, Shihui, Lan, Yang, Zhou, Haibo, Hu, Xinde, Wang, Xiaojing
• Format: Article
• Language: English
• Subjects: AAV; Animals; Antibodies; Antibodies, Neutralizing; Antibodies, Viral; Antigens; Coronaviruses; COVID-19; COVID-19 Vaccines; Dogs; Enzymes; Epidemics; Genomes; Humans; Immune response; Immunization; Immunogenicity; Mice; Mice, Inbred BALB C; Neutralizing; Neutralizing antibody; Pandemics; Peptides; Proteins; SARS-CoV-2; Severe acute respiratory syndrome coronavirus 2; Short Communication; Spike Glycoprotein, Coronavirus - genetics; Vaccine; Vaccines; Viral diseases; Viral Vaccines - genetics
• ISSN: 0264-410X; 1873-2518; 1873-2518
• DOI: 10.1016/j.vaccine.2022.01.030

•AAV based-vaccine could efficiently mediate the RBD protein expression of the SARS-CoV-2 in mammalian cells.•AAV based-vaccine could rapidly induce strong immune responses in mice, which maintaining at least six months.•AAV-3xRBD vaccine could elicit the high level of neutralizing antibodies against SARS-CoV-2 in mice.•AAV-3xRBD vaccine has the ability of inducing the specific antibodies against SARS-CoV-2 in canines. The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has resulted in catastrophic damage worldwide. Accordingly, the development of powerful, safe, easily accessible vaccines with long-term effectiveness is understood as an urgently needed countermeasure against this ongoing pandemic. Guided by this strong promise of using AAVs, we here designed, optimized, and developed an AAV-based vaccines (including AAV-RBD(max), AAV-RBD(wt), AAV-2xRBD, and AAV-3xRBD) that elicit strong immune responses against the RBD domain of the SARS-CoV-2 S protein. These immunogenic responses have proven long-lived, with near peak levels for at least six months in mice. Notably, the sera immunized with AAV-3xRBD vaccine contains powerful neutralizing antibodies against the SARS-CoV-2 pseudovirus. Further evidence proven that potent specific antibodies could also be elicited in canines after vaccination with AAV-3xRBD vaccine.