Marked Increase in Avidity of SARS-CoV-2 Antibodies 7–8 Months After Infection Is Not Diminished in Old Age. (4th June 2021)

• Record Type: Journal Article
• Authors: Pichler, Daniel; Baumgartner, Matthias; Kimpel, Janine; Rössler, Annika; Riepler, Lydia; Bates, Katie; Fleischer, Verena; von Laer, Dorothee; Borena, Wegene; Würzner, Reinhard
• Is Part Of: Journal of infectious diseases. Volume 224:Number 5(2021)
• Page Start: 764
• Page End: 770
• Publication Date: 2021-06-04
• Subjects: antibody avidity -- COVID-19 -- neutralization assay -- SARS-CoV-2 -- urea; Communicable diseases -- Periodicals; Diseases -- Causes and theories of causation -- Periodicals; Medicine -- Periodicals; Communicable Diseases -- Periodicals; Electronic journals; 616.9
• DOI: 10.1093/infdis/jiab300
• Languages: English
• ISSNs: 0022-1899

Abstract

Abstract: The kinetics of immunoglobulin G (IgG) avidity maturation during severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection obtained from 217 participants of the Ischgl cohort, Austria, was studied 0.5–1.5 months (baseline) and 7–8 months (follow-up) after infection. The IgG avidity assay, using a modified IgG enzyme-linked immunosorbent assay (ELISA) and 5.5 M urea, revealed that old age does not diminish the increase in avidity, detected in all participants positive at both time points, from 18% to 42%. High avidity was associated with a marked residual neutralization capacity in 97.2.% of participants (211/217), which was even higher in the older age group, revealing an important role of avidity assays as easy and cheap surrogate tests for assessing the maturation of the immune system conveying potential protection against further SARS-CoV-2 infections without necessitating expensive and laborious neutralization assays. Abstract : Avidity and neutralization data from 217 SARS-CoV2–infected antibody-positive subjects revealed a strong immune response 7–8 months postinfection in >97% of subjects, not diminished in old age. Easy and cheap avidity assays may thus compensate for expensive neutralization assays.