Frontiers in Immunology (Feb 2024)

Serum antibody fingerprinting of SARS-CoV-2 variants in infected and vaccinated subjects by label-free microarray biosensor

  • Thomas Carzaniga,
  • Luca Casiraghi,
  • Giovanni Nava,
  • Giuliano Zanchetta,
  • Tommaso Inzani,
  • Marcella Chiari,
  • Valentina Bollati,
  • Sara Epis,
  • Claudio Bandi,
  • Alessia Lai,
  • Gianguglielmo Zehender,
  • Tommaso Bellini,
  • Marco Buscaglia

DOI
https://doi.org/10.3389/fimmu.2024.1323406
Journal volume & issue
Vol. 15

Abstract

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Both viral infection and vaccination affect the antibody repertoire of a person. Here, we demonstrate that the analysis of serum antibodies generates information not only on the virus type that caused the infection but also on the specific virus variant. We developed a rapid multiplex assay providing a fingerprint of serum antibodies against five different SARS-CoV-2 variants based on a microarray of virus antigens immobilized on the surface of a label-free reflectometric biosensor. We analyzed serum from the plasma of convalescent subjects and vaccinated volunteers and extracted individual antibody profiles of both total immunoglobulin Ig and IgA fractions. We found that Ig level profiles were strongly correlated with the specific variant of infection or vaccination and that vaccinated subjects displayed a larger quantity of total Ig and a lower fraction of IgA relative to the population of convalescent unvaccinated subjects.

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