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Author Spotlight: Advancing Antiviral Strategies Through Novel Immunocapture and Mass Spectrometry Techniques
Published on: January 12, 2024
Dual ELISA using SARS-CoV-2 nucleocapsid protein produced in E. coli and CHO cells reveals epitope masking by
Airi Rump1, Robert Risti1, Mai-Ly Kristal1
1Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, 12618, Estonia.
Abstract:
Spike and nucleocapsid proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2-SP, SARS-CoV-2-NP) are the main immunogenic targets for antibodies. We herein demonstrate that the glycosylation of SARS-CoV-2-NP masks some of its antibody epitopes. In many cases, this can lead to false-negative serological tests. Deglycosylation of SARS-CoV-2-NP significantly increased the number of positive tests. The glycosylation pattern analysis of this protein revealed that the putative N-linked glycosylation sites, at the amino acid positions 48 and 270, co-located with two of the main immunodominant B cell epitopes.
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