Impact of glycan cloud on the B-cell epitope prediction of SARS-CoV-2 Spike protein
Autor
Wintjens, René
Makha Bifani, Amanda
Bifani, Pablo
Institución
Resumen
The SARS-CoV-2 outbreak originated in China in late 2019 and has since spread to pandemic proportions. Diagnostics, therapeutics
and vaccines are urgently needed. We model the trimeric Spike protein, including flexible loops and all N-glycosylation sites, in
order to elucidate accessible epitopes for antibody-based diagnostics, therapeutics and vaccine development. Based on published
experimental data, six homogeneous glycosylation patterns and two heterogeneous ones were used for the analysis. The glycan
chains alter the accessible surface areas on the S-protein, impeding antibody-antigen recognition. In presence of glycan, epitopes
on the S1 subunit, that notably contains the receptor binding domain, remain mostly accessible to antibodies while those present
on the S2 subunit are predominantly inaccessible. We identify 28 B-cell epitopes in the Spike structure and group them as nonaffected by the glycan cloud versus those which are strongly masked by the glycan cloud, resulting in a list of favourable epitopes
as targets for vaccine development, antibody-based therapy and diagnostics.