Complementarity determining regions in SARS-CoV-2 hybrid immunity

Front Immunol. 2023 Feb 21:14:1050037. doi: 10.3389/fimmu.2023.1050037. eCollection 2023.

Abstract

Pre-vaccination SARS-CoV-2 infection can boost protection elicited by COVID-19 vaccination and post-vaccination breakthrough SARS-CoV-2 infection can boost existing immunity conferred by COVID-19 vaccination. Such 'hybrid immunity' is effective against SARS-CoV-2 variants. In order to understand 'hybrid immunity' at the molecular level we studied the complementarity determining regions (CDR) of anti-RBD (receptor binding domain) antibodies isolated from individuals with 'hybrid immunity' as well as from 'naive' (not SARS-CoV-2 infected) vaccinated individuals. CDR analysis was done by liquid chromatography/mass spectrometry-mass spectrometry. Principal component analysis and partial least square differential analysis showed that COVID-19 vaccinated people share CDR profiles and that pre-vaccination SARS-CoV-2 infection or breakthrough infection further shape the CDR profile, with a CDR profile in hybrid immunity that clustered away from the CDR profile in vaccinated people without infection. Thus, our results show a CDR profile in hybrid immunity that is distinct from the vaccination-induced CDR profile.

Keywords: COVID-19; SARS-CoV-2; complementary determining region; hybrid immunity; vaccination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19 Vaccines
  • COVID-19* / prevention & control
  • Complementarity Determining Regions / genetics
  • Humans
  • SARS-CoV-2*

Substances

  • Complementarity Determining Regions
  • COVID-19 Vaccines

Supplementary concepts

  • SARS-CoV-2 variants

Grants and funding

The study was supported by a COVID-19 grant from KU Leuven (KOOR, Group Biomedical Sciences and University Hospitals Leuven) and by KU Leuven grant C3/20/105. PV is a senior clinical investigator of the Fund for Scientific Research — Flanders.