SARS-CoV-2-induced humoral immunity through B cell epitope analysis in COVID-19 infected individuals

• Published in: Scientific reports Vol. 11; no. 1; pp. 5934 - 13
• Main Authors: Yoshida, Shota, Ono, Chikako, Hayashi, Hiroki, Fukumoto, Shinya, Shiraishi, Satoshi, Tomono, Kazunori, Arase, Hisashi, Matsuura, Yoshiharu, Nakagami, Hironori
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 15.03.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 631/250; 692/420/254; Adaptive immunity; Amino Acid Sequence; Antibodies; Antibodies, Neutralizing - blood; Antibodies, Neutralizing - immunology; Antibodies, Viral - blood; Antibodies, Viral - immunology; Coronaviruses; COVID-19; COVID-19 - epidemiology; COVID-19 - immunology; COVID-19 - virology; Disease hot spots; Enzyme-Linked Immunosorbent Assay; Epitopes; Epitopes, B-Lymphocyte - immunology; Female; Host-Pathogen Interactions; Humanities and Social Sciences; Humans; Humoral immunity; Immunity, Humoral; Immunoglobulin G; Immunoglobulin M; Intensive care; Male; multidisciplinary; Proteins; SARS-CoV-2 - immunology; Science; Science (multidisciplinary); Severe acute respiratory syndrome coronavirus 2; Spike glycoprotein; Spike Glycoprotein, Coronavirus - chemistry; Spike Glycoprotein, Coronavirus - immunology; Vaccine development
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-85202-9

The aim of this study is to understand adaptive immunity to SARS-CoV-2 through the analysis of B cell epitope and neutralizing activity in coronavirus disease 2019 (COVID-19) patients. We obtained serum from forty-three COVID-19 patients from patients in the intensive care unit of Osaka University Hospital (n = 12) and in Osaka City Juso Hospital (n = 31). Most individuals revealed neutralizing activity against SARS-CoV-2 assessed by a pseudotype virus-neutralizing assay. The antibody production against the spike glycoprotein (S protein) or receptor-binding domain (RBD) of SARS-CoV-2 was elevated, with large individual differences, as assessed by ELISA. We observed the correlation between neutralizing antibody titer and IgG, but not IgM, antibody titer of COVID-19 patients. In the analysis of the predicted the linear B cell epitopes, hot spots in the N-terminal domain of the S protein were observed in the serum from patients in the intensive care unit of Osaka University Hospital. Overall, the analysis of antibody production and B cell epitopes of the S protein from patient serum may provide a novel target for the vaccine development against SARS-CoV-2.