Employment of a high throughput functional assay to define the critical factors that influence vaccine induced cross-variant neutralizing antibodies for SARS-CoV-2

• Published in: Scientific reports Vol. 13; no. 1; p. 21810
• Main Authors: Gu, Yue, Shunmuganathan, Bhuvaneshwari, Qian, Xinlei, Gupta, Rashi, Tan, Rebecca S. W., Kozma, Mary, Purushotorman, Kiren, Murali, Tanusya M., Tan, Nikki Y. J., Preiser, Peter R., Lescar, Julien, Nasir, Haziq, Somani, Jyoti, Tambyah, Paul A., Smith, Kenneth G. C., Renia, Laurent, Ng, Lisa F. P., Lye, David C., Young, Barnaby E., MacAry, Paul A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09.12.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 631/1647; 631/250; 631/337; 631/61; 692/308; 692/699; Antibodies; Comorbidity; COVID-19; COVID-19 vaccines; Humanities and Social Sciences; Immunity; Monoclonal antibodies; multidisciplinary; Nucleocapsids; Science; Science (multidisciplinary); Serology; Severe acute respiratory syndrome coronavirus 2; Vaccines
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-023-49231-w

The scale and duration of neutralizing antibody responses targeting SARS-CoV-2 viral variants represents a critically important serological parameter that predicts protective immunity for COVID-19. In this study, we describe the development and employment of a new functional assay that measures neutralizing antibodies for SARS-CoV-2 and present longitudinal data illustrating the impact of age, sex and comorbidities on the kinetics and strength of vaccine-induced antibody responses for key variants in an Asian volunteer cohort. We also present an accurate quantitation of serological responses for SARS-CoV-2 that exploits a unique set of in-house, recombinant human monoclonal antibodies targeting the viral Spike and nucleocapsid proteins and demonstrate a reduction in neutralizing antibody titres across all groups 6 months post-vaccination. We also observe a marked reduction in the serological binding activity and neutralizing responses targeting recently newly emerged Omicron variants including XBB 1.5 and highlight a significant increase in cross-protective neutralizing antibody responses following a third dose (boost) of vaccine. These data illustrate how key virological factors such as immune escape mutations combined with host demographic factors such as age and sex of the vaccinated individual influence the strength and duration of cross-protective serological immunity for COVID-19.