SARS-CoV-2 epitope-specific T cells: Immunity response feature, TCR repertoire characteristics and cross-reactivity

Front Immunol. 2023 Mar 10:14:1146196. doi: 10.3389/fimmu.2023.1146196. eCollection 2023.

Abstract

The devastating COVID-19 pandemic caused by SARS-CoV-2 and multiple variants or subvariants remains an ongoing global challenge. SARS-CoV-2-specific T cell responses play a critical role in early virus clearance, disease severity control, limiting the viral transmission and underpinning COVID-19 vaccine efficacy. Studies estimated broad and robust T cell responses in each individual recognized at least 30 to 40 SARS-CoV-2 antigen epitopes and associated with COVID-19 clinical outcome. Several key immunodominant viral proteome epitopes, including S protein- and non-S protein-derived epitopes, may primarily induce potent and long-lasting antiviral protective effects. In this review, we summarized the immune response features of immunodominant epitope-specific T cells targeting different SRAS-CoV-2 proteome structures after infection and vaccination, including abundance, magnitude, frequency, phenotypic features and response kinetics. Further, we analyzed the epitopes immunodominance hierarchy in combination with multiple epitope-specific T cell attributes and TCR repertoires characteristics, and discussed the significant implications of cross-reactive T cells toward HCoVs, SRAS-CoV-2 and variants of concern, especially Omicron. This review may be essential for mapping the landscape of T cell responses toward SARS-CoV-2 and optimizing the current vaccine strategy.

Keywords: SARS-CoV-2; T cell immunity; TCR repertoire; cross-reactivity; epitopes.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19 Vaccines
  • COVID-19*
  • Epitopes
  • Humans
  • Immunity
  • Immunodominant Epitopes
  • Pandemics
  • Proteome
  • Receptors, Antigen, T-Cell
  • SARS-CoV-2*
  • T-Lymphocytes

Substances

  • Epitopes
  • COVID-19 Vaccines
  • Proteome
  • Immunodominant Epitopes
  • Receptors, Antigen, T-Cell

Grants and funding

This work was supported by the National Key Research and Development Program of China [2019YFC0810900], Ministry of Science and Technology of the People Republic of China [2021YFC0864400], NSFC [81971485, 82271801], Guangdong Basic and Applied Basic Research Foundation [2019B1515120068, 2020B1111330001, 2022B1111070002], Emergency Key Program of Guangzhou Laboratory [No.EKPG21-30-1], China Postdoctoral Science Foundation [2021M690792] and Zhongnanshan Medical Foundation of Guangdong Province [ZNSA-2020013].