Selective and cross-reactive SARS-CoV-2 T cell epitopes in unexposed humans

Preexisting immune response to SARS-CoV-2 Robust T cell responses to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus occur in most individuals with coronavirus disease 2019 (COVID-19). Several studies have reported that some people who have not been exposed to SARS-CoV-2 have preexisting reactivity to SARS-CoV-2 sequences. The immunological mechanisms underlying this preexisting reactivity are not clear, but previous exposure to widely circulating common cold coronaviruses might be involved. Mateus et al. found that the preexisting reactivity against SARS-CoV-2 comes from memory T cells and that cross-reactive T cells can specifically recognize a SARS-CoV-2 epitope as well as the…

• NI
  National Institutes of Health

  Awards: AI142742, U19 AI118626, AI135078, 75N9301900065
• UO
  University of California, San Diego

  Awards: AI007036, AI007384
• NI
  National Institute of Allergy and Infectious Diseases

  Award: AI036214