Site-specific N-glycosylation Characterization of Recombinant SARS-CoV-2 Spike Proteins using High-Resolution Mass Spectrometry

Yong Zhang; Wanjun Zhao; Yonghong Mao; Shisheng Wang; Yi Zhong; Tao Su; Meng Gong; Xiaofeng Lu; Jingqiu Cheng; Hao Yang

Intriguingly, the immature N-glycans such as high-mannose are regarded as "non-self" glycans (35, 36). Therefore, the insect cell-expressed recombinant antigens decorated with paucimannose and high mannose are more immunogenic in mice than those The insect cell-produced S protein subunits could prime protective immunity against the "non-self" oligomannose N-glycans, in case of the immature N-glycans linked to the native envelope proteins of SARS-CoV-2, which seems to occur in the SARS-CoV replication(35). In contrast, the human cell-expressed S protein subunits as vaccines mimic the "self" glycans in human, which are not expected to boost immune response to the glycoantigens. However, the remaining accessible and non-glycosylated regions can serve as the antigens and epitopes. The rational design of antigens to prime potent and broad immune responses against accessible epitopes on SARS-CoV S protein is essential and promising. The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.28.013276 doi: bioRxiv preprint