SARS-CoV-2-specific circulating T follicular helper cells correlate with neutralizing antibodies and increase during early convalescence

PLoS Pathog. 2021 Jul 16;17(7):e1009761. doi: 10.1371/journal.ppat.1009761. eCollection 2021 Jul.

Abstract

T-cell immunity is likely to play a role in protection against SARS-CoV-2 by helping generate neutralizing antibodies. We longitudinally studied CD4 T-cell responses to the M, N, and S structural proteins of SARS-CoV-2 in 26 convalescent individuals. Within the first two months following symptom onset, a majority of individuals (81%) mounted at least one CD4 T-cell response, and 48% of individuals mounted detectable SARS-CoV-2-specific circulating T follicular helper cells (cTfh, defined as CXCR5+PD1+ CD4 T cells). SARS-CoV-2-specific cTfh responses across all three protein specificities correlated with antibody neutralization with the strongest correlation observed for S protein-specific responses. When examined over time, cTfh responses, particularly to the M protein, increased in convalescence, and robust cTfh responses with magnitudes greater than 5% were detected at the second convalescent visit, a median of 38 days post-symptom onset. CD4 T-cell responses declined but persisted at low magnitudes three months and six months after symptom onset. These data deepen our understanding of antigen-specific cTfh responses in SARS-CoV-2 infection, suggesting that in addition to S protein, M and N protein-specific cTfh may also assist in the development of neutralizing antibodies and that cTfh response formation may be delayed in SARS-CoV-2 infection.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Antibodies, Neutralizing / blood*
  • Antibodies, Viral / blood*
  • Antibody Specificity
  • COVID-19 / immunology*
  • COVID-19 / virology*
  • Case-Control Studies
  • Coronavirus Nucleocapsid Proteins / immunology
  • Female
  • Host Microbial Interactions / immunology
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Pandemics
  • Phosphoproteins / immunology
  • SARS-CoV-2 / immunology*
  • Spike Glycoprotein, Coronavirus / immunology
  • T Follicular Helper Cells / immunology*
  • T Follicular Helper Cells / virology*
  • Time Factors
  • Viral Matrix Proteins / immunology
  • Young Adult

Substances

  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Coronavirus Nucleocapsid Proteins
  • Phosphoproteins
  • Spike Glycoprotein, Coronavirus
  • Viral Matrix Proteins
  • membrane protein, SARS-CoV-2
  • nucleocapsid phosphoprotein, SARS-CoV-2
  • spike protein, SARS-CoV-2