Highly specific monoclonal antibodies and epitope identification against SARS-CoV-2 nucleocapsid protein for antigen detection tests.

Abstract

The ongoing coronavirus disease 2019 (COVID-19) pandemic is a major global public health concern. Although rapid point-of-care testing for detecting viral antigen is important for management of the outbreak, the current antigen tests are less sensitive than nucleic acid testing. In our current study, we produce monoclonal antibodies (mAbs) that exclusively react with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and exhibit no cross-reactivity with other human coronaviruses, including SARS-CoV. Molecular modeling suggests that the mAbs bind to epitopes present on the exterior surface of the nucleocapsid, making them suitable for detecting SARS-CoV-2 in clinical samples. We further select the optimal pair of anti-SARS-CoV-2 nucleocapsid protein (NP) mAbs using ELISA and then use this mAb pair to develop immunochromatographic assay augmented with silver amplification technology. Our mAbs recognize the variants of concern (501Y.V1-V3) that are currently in circulation. Because of their high performance, the mAbs of this study can serve as good candidates for developing antigen detection kits for COVID-19.

• Authors: Yutaro Yamaoka, Kei Miyakawa, Sundararaj Stanleyraj Jeremiah, Rikako Funabashi, Koji Okudela, Sayaka Kikuchi, Junichi Katada, Atsuhiko Wada, Toshiki Takei, Mayuko Nishi, Kohei Shimizu, Hiroki Ozawa, Shuzo Usuku, Chiharu Kawakami, Nobuko Tanaka, Takeshi Morita, Hiroyuki Hayashi, Hideaki Mitsui, Keita Suzuki, Daisuke Aizawa, Yukihiro Yoshimura, Tomoyuki Miyazaki, Etsuko Yamazaki, Tadaki Suzuki, Hirokazu Kimura, Hideaki Shimizu, Nobuhiko Okabe, Hideki Hasegawa, Akihide Ryo
• Journal: Cell reports. Medicine (Cell Rep Med) Vol. 2 Issue 6 Pg. 100311 (06 15 2021) ISSN: 2666-3791 [Electronic] United States
• PMID: 34027498 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2021 The Authors.

Chemical References

• Antibodies, Monoclonal
• Coronavirus Nucleocapsid Proteins
• Epitopes
• Phosphoproteins
• nucleocapsid phosphoprotein, SARS-CoV-2
• Silver

Topics

• Animals
• Antibodies, Monoclonal (immunology)
• Antigen-Antibody Reactions
• COVID-19 (pathology, virology)
• Coronavirus Nucleocapsid Proteins (genetics, immunology, metabolism)
• Epitopes (immunology)
• Humans
• Immunization
• Immunoassay (methods)
• Mice
• Mice, Inbred BALB C
• Phosphoproteins (genetics, immunology, metabolism)
• Point-of-Care Systems
• SARS-CoV-2 (isolation & purification, metabolism)
• Silver (chemistry)