Neutralisation hierarchy of SARS-CoV-2 variants of concern using standardised, quantitative neutralisation assays reveals a correlation with disease severity; towards deciphering protective antibody thresholds

Cantoni, D. et al. (2022) Neutralisation hierarchy of SARS-CoV-2 variants of concern using standardised, quantitative neutralisation assays reveals a correlation with disease severity; towards deciphering protective antibody thresholds. Frontiers in Immunology, 13, 773982. (doi: 10.3389/fimmu.2022.773982) (PMID:35330908) (PMCID:PMC8940306)

Abstract

The rise of SARS-CoV-2 variants has made the pursuit to define correlates of protection more troublesome, despite the availability of the World Health Organisation (WHO) International Standard for anti-SARS-CoV-2 Immunoglobulin sera, a key reagent used to standardise laboratory findings into an international unitage. Using pseudotyped virus, we examine the capacity of convalescent sera, from a well-defined cohort of healthcare workers (HCW) and Patients infected during the first wave from a national critical care centre in the UK to neutralise B.1.1.298, variants of interest (VOI) B.1.617.1 (Kappa), and four VOCs, B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma) and B.1.617.2 (Delta), including the B.1.617.2 K417N, informally known as Delta Plus. We utilised the WHO International Standard for anti-SARS-CoV-2 Immunoglobulin to report neutralisation antibody levels in International Units per mL. Our data demonstrate a significant reduction in the ability of first wave convalescent sera to neutralise the VOCs. Patients and HCWs with more severe COVID-19 were found to have higher antibody titres and to neutralise the VOCs more effectively than individuals with milder symptoms. Using an estimated threshold for 50% protection, 54 IU/mL, we found most asymptomatic and mild cases did not produce titres above this threshold.

• Item Type: Articles
• Additional Information: This study was undertaken by the Humoral Immune Correlates to COVID-19 (HICC) consortium, funded by the UKRI and NIHR; grant number G107217 (COV0170 - HICC: Humoral Immune Correlates for COVID19).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Cantoni, Dr Diego
• Authors: Cantoni, D., Mayora-Neto, M., Nadesalingam, A., Wells, D. A., Carnell, G. W., Ohlendorf, L., Ferrari, M., Palmer, P., Chan, A. C.Y., Smith, P., Bentley, E. M., Einhauser, S., Wagner, R., Page, M., Raddi, G., Baxendale, H., Castillo-Olivares, J., Heeney, J., and Temperton, N.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Frontiers in Immunology
• Publisher: Frontiers Media
• ISSN: 1664-3224
• ISSN (Online): 1664-3224
• Copyright Holders: Copyright © 2022 Cantoni, Mayora-Neto, Nadesalingam, Wells, Carnell, Ohlendorf, Ferrari, Palmer, Chan, Smith, Bentley, Einhauser, Wagner, Page, Raddi, Baxendale, Castillo-Olivares, Heeney and Temperton
• First Published: First published in Frontiers in Immunology 13: 773982
• Publisher Policy: Reproduced under a Creative Commons licence