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Negative selection imparts peptide specificity to the mature T cell repertoire.

ABSTRACT: The T cell alphabeta receptor (TCR) recognizes foreign peptide antigens bound to proteins encoded in the MHC. The MHC portion of this complex contributes much to the footprint of the TCR on the ligand, yet T cells are usually very specific for individual foreign peptides. Here, we show that the development of peptide-specific T cells is not intrinsic to thymocytes that undergo thymic-positive selection but is an outcome of eliminating, through negative selection, thymocytes bearing TCRs with extensive peptide cross-reactivity. Hence, thymic-negative selection imposes peptide specificity on the mature T cell repertoire.

SUBMITTER: Huseby ES

PROVIDER: S-EPMC208798 | biostudies-literature | 2003 Sep

REPOSITORIES: biostudies-literature

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Negative selection imparts peptide specificity to the mature T cell repertoire.

Huseby Eric S ES Crawford Frances F White Janice J Kappler John J Marrack Philippa P

Proceedings of the National Academy of Sciences of the United States of America 20030922 20

The T cell alphabeta receptor (TCR) recognizes foreign peptide antigens bound to proteins encoded in the MHC. The MHC portion of this complex contributes much to the footprint of the TCR on the ligand, yet T cells are usually very specific for individual foreign peptides. Here, we show that the development of peptide-specific T cells is not intrinsic to thymocytes that undergo thymic-positive selection but is an outcome of eliminating, through negative selection, thymocytes bearing TCRs with ext ...[more]

PMID: 14504410

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