The coronavirus disease 2019 (COVID-19) pandemic has reached an unprecedented level. There is a strong demand for diagnostic and serological supplies worldwide, making it necessary for countries to establish their own technologies to produce high-quality biomolecules. The two main viral antigens used for the diagnostics for severe acute respiratory syndrome coronavirus (SARS-CoV-2) are the structural proteins spike (S) protein and nucleocapsid (N) protein. The spike protein of SARS-CoV-2 is cleaved into S1 and S2, in which the S1 subunit has the receptor-binding domain (RBD), which induces the production of neutralizing antibodies, whereas nucleocapsid is an ideal target for viral antigen-based detection. In this study, we designed plasmids, pcDNA3.1/S1 and pcDNA3.1/N, and optimized their expression of the recombinant S1 and N proteins from SARS-CoV-2 in a mammalian system. The RBD was used as a control. The antigens were successfully purified from Expi293 cells, with high yields of the S1, N, and RBD proteins. The immunogenic abilities of these proteins were demonstrated in a mouse model. Further, enzyme-linked immunosorbent assays with human serum samples showed that the SARS-CoV-2 antigens are a suitable alternative for serological assays to identify patients infected with COVID-19.
【저자키워드】 coronavirus disease, severe acute respiratory syndrome coronavirus 2, Spike protein, Receptor binding domain, nucleocapsid, 【초록키워드】 COVID-19, SARS-CoV-2, coronavirus, pandemic, Neutralizing antibodies, diagnostic, diagnostics, Antigen, Protein, enzyme-linked immunosorbent assay, Serological assay, cells, RBD, Patient, N protein, structural protein, serological, expression, human serum, Viral antigen, acute respiratory syndrome, immunogenic, plasmids, RBD proteins, mammalian, country, the S1 subunit, identify, S1 and S2, was used, demonstrated, the receptor-binding domain, induce, reached, purified, cleaved, infected with COVID-19, the SARS-CoV-2, 【제목키워드】 application, recombinant, RBD of SARS-CoV-2, Potential,