Deletion of CD4 and CD8 coreceptors permits generation of alphabetaT cells that recognize antigens independently of the MHC.


Journal Article

The thymus generates major histocompatibility complex (MHC)-restricted alphabetaT cells that only recognize antigenic ligands in association with MHC or MHC-like molecules. We hypothesized that MHC specificity might be imposed on a broader alphabetaTCR repertoire during thymic selection by CD4 and CD8 coreceptors that bind and effectively sequester the tyrosine kinase Lck, thereby preventing T cell receptor (TCR) signaling by non-MHC ligands that do not engage either coreceptor. This hypothesis predicts that, in coreceptor-deficient mice, alphabeta thymocytes would be signaled by non-MHC ligands to differentiate into alphabetaT cells lacking MHC specificity. We now report that MHC-independent alphabetaT cells were indeed generated in mice deficient in both coreceptors as well as MHC ("quad-deficient" mice) and that such mice contained a diverse alphabetaT cell repertoire whose MHC independence was confirmed at the clonal level. We conclude that CD4 and CD8 coreceptors impose MHC specificity on a broader alphabetaTCR repertoire during thymic selection by preventing thymocytes from being signaled by non-MHC ligands.

Full Text

Duke Authors

Cited Authors

  • Van Laethem, F; Sarafova, SD; Park, J-H; Tai, X; Pobezinsky, L; Guinter, TI; Adoro, S; Adams, A; Sharrow, SO; Feigenbaum, L; Singer, A

Published Date

  • November 2007

Published In

Volume / Issue

  • 27 / 5

Start / End Page

  • 735 - 750

PubMed ID

  • 18023370

Pubmed Central ID

  • 18023370

International Standard Serial Number (ISSN)

  • 1074-7613

Digital Object Identifier (DOI)

  • 10.1016/j.immuni.2007.10.007


  • eng

Conference Location

  • United States