Functional SARS-CoV-2 cross-reactive CD4⁺ T cells established in early childhood decline with age.

ABSTRACT: Pre-existing SARS-CoV-2-reactive T cells have been identified in SARS-CoV-2-unexposed individuals, potentially modulating COVID-19 and vaccination outcomes. Here, we provide evidence that functional cross-reactive memory CD4⁺ T cell immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is established in early childhood, mirroring early seroconversion with seasonal human coronavirus OC43. Humoral and cellular immune responses against OC43 and SARS-CoV-2 were assessed in SARS-CoV-2-unexposed children (paired samples at age two and six) and adults (age 26 to 83). Pre-existing SARS-CoV-2-reactive CD4⁺ T cell responses targeting spike, nucleocapsid, and membrane were closely linked to the frequency of OC43-specific memory CD4⁺ T cells in

SUBMITTER: Humbert M 

PROVIDER: S-EPMC10041119 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature