A novel linker-immunodominant site (LIS) vaccine targeting the SARS-CoV-2 spike protein protects against severe COVID-19 in Syrian hamsters

• Published in: Emerging microbes & infections 2021-01, Vol.10 (1), p.874-884
• Main Authors: Zhang, Bao-Zhong, Wang, Xiaolei, Yuan, Shuofeng, Li, Wenjun, Dou, Ying, Poon, Vincent Kwok-Man, Chan, Chris Chung-Sing, Cai, Jian-Piao, Chik, Kenn KaHeng, Tang, Kaiming, Chan, Chris Chun-Yiu, Hu, Ye-Fan, Hu, Jing-Chu, Badea, Smaranda Ruxandra, Gong, Hua-Rui, Lin, Xuansheng, Chu, Hin, Li, Xuechen, To, Kelvin Kai-Wang, Liu, Li, Chen, Zhiwei, Hung, Ivan Fan-Ngai, Yuen, Kwok Yung, Chan, Jasper Fuk-Woo, Huang, Jian-Dong
• Format: Article
• Language: English
• Subjects: COVID-19; linker-immunodominant site; SARS-CoV-2; spike protein; vaccine
• ISSN: 2222-1751; 2222-1751
• DOI: 10.1080/22221751.2021.1921621

The Coronavirus Disease 2019 (COVID-19) pandemic is unlikely to abate until sufficient herd immunity is built up by either natural infection or vaccination. We previously identified ten linear immunodominant sites on the SARS-CoV-2 spike protein of which four are located within the RBD. Therefore, we designed two linkerimmunodominant site (LIS) vaccine candidates which are composed of four immunodominant sites within the RBD (RBD-ID) or all the 10 immunodominant sites within the whole spike (S-ID). They were administered by subcutaneous injection and were tested for immunogenicity and in vivo protective efficacy in a hamster model for COVID-19. We showed that the S-ID vaccine induced significantly better neutralizing antibody response than RBD-ID and alum control. As expected, hamsters vaccinated by S-ID had significantly less body weight loss, lung viral load, and histopathological changes of pneumonia. The S-ID has the potential to be an effective vaccine for protection against COVID-19.