Site-specific analysis of the SARS-CoV-2 glycan shield

Yasunori Watanabe; Joel D. Allen; Daniel Wrapp; Jason S. McLellan; Max Crispin

Our glycosylation analysis of SARS-CoV-2 offers a detailed benchmark of site-specific glycan signatures characteristic of a natively folded trimeric spike. As an increasing number of glycoprotein-based vaccine candidates are being developed, their detailed glycan analysis offers a route for comparing immunogen integrity and will also be important to monitor as manufacturing processes are scaled for clinical use. Glycosylation will therefore also be an important measure of antigen quality in the manufacture of serological testing kits, particularly as some S protein fragments may offer advantages in terms of production yield but lack effective glycan mimicry of the natively folded trimeric spike. The lower levels of mannose-. CC-BY 4.0 International license author/funder. It is made available under a The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.26.010322 doi: bioRxiv preprint terminating glycans on SARS-CoV-2 compared to many other viral spikes may indicate that glycan engineering should be considered in the scenario where first-generation glycoproteinbased vaccine candidates be poorly immunogenic. Finally, with the advent of nucleotide-based vaccines it will be important to understand how those delivery mechanisms impact immunogen processing and presentation.