Glycan Engineering of SARS-CoV-2 RBD Elicits Cross-Neutralizing Antibodies

Researchers at Osaka University in Japan have used glycan engineering to develop a vaccination strategy in mice that promotes the production of antibodies that can neutralize not only SARS-CoV-2 but a broad range of other coronaviruses as well. If successfully translated to humans, the approach, to be published in the Journal of Experimental Medicine, could lead to the development of a next-generation vaccine. 

The researchers genetically engineered the receptor-binding domain of the SARS-CoV-2 spike protein, covering its head region in additional sugar molecules. Theoretically, the glycans could shield the head region from the immune system and boost the production of antibodies against the unshielded core region of the receptor-binding domain.

Indeed, mice immunized with these engineered glycans produced a much higher proportion of antibodies recognizing the core region of the spike protein receptor-binding domain. These antibodies were able to neutralize the cellular entry of not only SARS-CoV-2 but also SARS-CoV-1 and three SARS-like coronaviruses from bats and pangolins.

Lead researcher Tomohiro Kurosaki concluded, “Our data suggest that engineered versions of the spike receptor-binding domain could be a useful component for the development of broadly protective, next-generation vaccines to prevent future coronavirus pandemics.”