Impact of SARS-CoV-2 exposure history on the T cell and IgG response

Cell Rep Med. 2023 Jan 17;4(1):100898. doi: 10.1016/j.xcrm.2022.100898. Epub 2022 Dec 22.

Abstract

Multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposures, from infection or vaccination, can potently boost spike antibody responses. Less is known about the impact of repeated exposures on T cell responses. Here, we compare the prevalence and frequency of peripheral SARS-CoV-2-specific T cell and immunoglobulin G (IgG) responses in 190 individuals with complex SARS-CoV-2 exposure histories. As expected, an increasing number of SARS-CoV-2 spike exposures significantly enhances the magnitude of IgG responses, while repeated exposures improve the number of T cell responders but have less impact on SARS-CoV-2 spike-specific T cell frequencies in the circulation. Moreover, we find that the number and nature of exposures (rather than the order of infection and vaccination) shape the spike immune response, with spike-specific CD4 T cells displaying a greater polyfunctional potential following hybrid immunity compared with vaccination only. Characterizing adaptive immunity from an evolving viral and immunological landscape may inform vaccine strategies to elicit optimal immunity as the pandemic progress.

Keywords: Ad26.COV2.S vaccine; COVID-19; IgG response; SARS-CoV-2; T cell response; hybrid immunity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Antibody Formation
  • CD4-Positive T-Lymphocytes
  • COVID-19* / epidemiology
  • Humans
  • Immunoglobulin G*
  • SARS-CoV-2
  • T-Lymphocytes*

Substances

  • Immunoglobulin G