Discovery of anti-SARS-CoV-2 S2 protein antibody CV804 with broad-spectrum reactivity with various beta coronaviruses and analysis of its pharmacological properties in vitro and in vivo
Yoji Tsugawa , Kentaro Furukawa, Tomoko Ise, Masahiro Takayama, Takeshi Ota, Takayuki Kuroda,Shinya Shano, Takashi Hashimoto, Haruyo Konishi, Takeshi Ishihara, Masaaki Sato, Haruhiko Kamada, Keita Fukao, Takao Shishido, Mai Yoshikawa, Tatsuya Takahashi, Satoshi Nagata
Abstract
The SARS-CoV-2 pandemic alerted the potential for significant harm due to future cross-species transmission of various animal coronaviruses to human. There is a significant need of antibody-based drugs to treat patients infected with previously unseen coronaviruses. In this study, we generated CV804, an antibody that binds to the S2 domain of SARS-CoV-2 spike protein, which is highly conserved across the coronavirus family and less susceptible to mutations. CV804 demonstrated broad cross-reactivities not only disease-associated human beta coronaviruses including SARS-CoV, MERS-CoV, HCoV-OC43, HCoV-HKU1 and with existing mutant strains of SARS-CoV-2 and but also with 20 representative animal-origin coronaviruses.
Introduction
The COVID-19 pandemic, caused by the SARS-CoV-2 beta coronavirus discovered in 2019, has had a severe impact on the global health and economy [1]. Besides COVID-19, various coronaviruses have caused a range of infectious diseases likely through animal-to-human spillover, posing a significant threat to public health. Coronaviridae contains four genera based on antigenicity and genetic criteria: alpha, beta, gamma, and delta [2]. Common human coronaviruses, such as HCoV-OC43, HCoV-HKU1 (beta coronaviruses), and HCoV-229E and HCoV-NL63 (alpha coronaviruses), are known to circulate annually and cause mild to moderate upper respiratory tract diseases [3, 4].
Materials and method
Plasmids
Expression plasmids for full-length spike proteins of SARS-CoV-2 or other corona-related viruses were constructed for DNA-immunization and binding assay by flow cytometry. Amino acid sequence of each spike protein was codon-optimized and its cDNA was synthesized (Azenta), and the cDNA fragment was inserted into the pcDNA 3.1 Hygro(+) vector (ThermoFisher Scientific) with fragments of IRES and cDNA of TagBFP (evrogen).
Results
Antibody isolation and binding activity to S protein
To obtain antibodies that effectively bind to a wide range of coronaviruses, we targeted S2 subunit of the spike protein of SARS-CoV-2. For immunization, plasmid DNAs encoding full-length SARS-CoV-2 S protein or S2 domain, full-length SARS-CoV-2 S protein or S2 domain-expressing cells or purified full-length SARS-CoV-2 S protein or S2 domain were used. Using the antiserum, we confirmed their binding to the S2 region and various coronaviruses, including MERS-CoV and SARS-CoV.
Discussion
Antibody therapeutics against novel coronavirus infection should possess excellent specificity and efficacy. However, problems arise due to the emergence of virus variants resistant to nAbs, resulting in loss of efficacy, as well as difficulty in generating broadly reactive antibodies that can target diverse viruses. In this study, we successfully developed an anti-SARS-CoV-2 spike 2 antibody CV804 that exhibits therapeutic effects by utilizing antibody effector functions in the host, which is distinct from traditional virus-nAbs.
Acknowledgments
We are grateful to all our colleagues who participated in the COVID-19 antiviral program at Shionogi and thank Shionogi TechnoAdvance Research Co., Ltd. for technical support in the pharmacological studies. The authors thank Sayuri Okamoto, Mayumi Niiyama, Kayoko Kato, Akiko Okabe, Madoka Takeshima, Eiko Moriishi, and Futaba Makimura who participated in the COVID-19 antiviral program at Laboratory of Antibody Design, Center for Drug Design Research, National Institutes of Biomedical Innovation, Health and Nutrition for technical support in the pharmacological studies.
Citation: Tsugawa Y, Furukawa K, Ise T, Takayama M, Ota T, Kuroda T, et al. (2024) Discovery of anti-SARS-CoV-2 S2 protein antibody CV804 with broad-spectrum reactivity with various beta coronaviruses and analysis of its pharmacological properties in vitro and in vivo. PLoS ONE 19(12): e0300297. https://doi.org/10.1371/journal.pone.0300297
Editor: Cheorl-Ho Kim, Sungkyunkwan University - Suwon Campus: Sungkyunkwan University - Natural Sciences Campus, REPUBLIC OF KOREA
Received: February 26, 2024; Accepted: September 10, 2024; Published: December 2, 2024
Copyright: © 2024 Tsugawa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the manuscript and its Supporting information files.
Funding: This work was supported in part by Japan Agency for Medical Research and Development (AMED) grant number JP21fk0108554. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
