Vaccination reshapes the virus-specific T cell repertoire in unexposed adults.

ABSTRACT: We examined how baseline CD4⁺ T cell repertoire and precursor states impact responses to pathogen infection in humans using primary immunization with yellow fever virus (YFV) vaccine. YFV-specific T cells in unexposed individuals were identified by peptide-MHC tetramer staining and tracked pre- and post-vaccination by tetramers and TCR sequencing. A substantial number of YFV-reactive T cells expressed memory phenotype markers and contained expanded clones in the absence of exposure to YFV. After vaccination, pre-existing YFV-specific T cell populations with low clonal diversity underwent limited expansion, but rare populations with a reservoir of unexpanded TCRs generated robust responses. These altered dynamics reorganized the immunodominance hierarchy and resulted in an overal

SUBMITTER: Pan YG 

PROVIDER: S-EPMC8192456 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature