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

• Published in: Cell reports. Medicine Vol. 2; no. 6; p. 100311
• Main Authors: Yamaoka, Yutaro, Miyakawa, Kei, Jeremiah, Sundararaj Stanleyraj, Funabashi, Rikako, Okudela, Koji, Kikuchi, Sayaka, Katada, Junichi, Wada, Atsuhiko, Takei, Toshiki, Nishi, Mayuko, Shimizu, Kohei, Ozawa, Hiroki, Usuku, Shuzo, Kawakami, Chiharu, Tanaka, Nobuko, Morita, Takeshi, Hayashi, Hiroyuki, Mitsui, Hideaki, Suzuki, Keita, Aizawa, Daisuke, Yoshimura, Yukihiro, Miyazaki, Tomoyuki, Yamazaki, Etsuko, Suzuki, Tadaki, Kimura, Hirokazu, Shimizu, Hideaki, Okabe, Nobuhiko, Hasegawa, Hideki, Ryo, Akihide
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 15.06.2021; Elsevier
• Subjects: Animals; Antibodies, Monoclonal - immunology; Antigen-Antibody Reactions; Coronavirus Nucleocapsid Proteins - genetics; Coronavirus Nucleocapsid Proteins - immunology; Coronavirus Nucleocapsid Proteins - metabolism; COVID-19; COVID-19 - pathology; COVID-19 - virology; Epitopes - immunology; Humans; Immunization; Immunoassay - methods; Mice; Mice, Inbred BALB C; monoclonal antibody; nucleoprotein; Phosphoproteins - genetics; Phosphoproteins - immunology; Phosphoproteins - metabolism; Point-of-Care Systems; point-of-care testing; SARS-CoV-2; SARS-CoV-2 - isolation & purification; SARS-CoV-2 - metabolism; Silver - chemistry; COVID-19; point-of-care testing; nucleoprotein; SARS-CoV-2; monoclonal antibody
• ISSN: 2666-3791; 2666-3791
• DOI: 10.1016/j.xcrm.2021.100311

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. [Display omitted] The monoclonal antibodies of this study have distinct epitopes to detect SARS-CoV-2They exhibit no cross-reactivity with other viruses, including SARS-CoVThese antibodies accurately detect the major SARS-CoV-2 variants of concernCoupling rapid antigen test with silver amplification enhances the test performance In this study, Yamaoka et al. report their highly specific, epitope-characterized monoclonal antibodies that exclusively detect SARS-CoV-2. These monoclonal antibodies, when used in a lateral flow immunoassay coupled with silver amplification, enhance the performance of rapid antigen detection tests for COVID-19.