A T cell receptor flattens a bulged antigenic peptide presented by a major histocompatibility complex class I molecule Academic Article uri icon


  • Plasticity of the T cell receptor (TCR) is a hallmark of major histocompatibility complex (MHC)-restricted T cell recognition. However, it is unclear whether interactions of TCR and peptide-MHC class I (pMHCI) always conform to this paradigm. Here we describe the structure of a TCR, ELS4, in its non-ligand-bound form and in complex with a prominent 'bulged' Epstein-Barr virus peptide bound to HLA-B(*)3501. This complex was atypical of previously characterized TCR-pMHCI interactions in that a rigid face of the TCR crumpled the bulged antigenic determinant. This peptide 'bulldozing' created a more featureless pMHCI determinant, allowing the TCR to maximize MHC class I contacts essential for MHC class I restriction of TCR recognition. Our findings represent a mechanism of antigen recognition whereby the plasticity of the T cell response is dictated mainly by adjustments in the MHC-bound peptide.


  • Tynan, Fleur E
  • Reid, Hugh H
  • Kjer-Nielsen, Lars
  • Miles, John J
  • Wilce, Matthew CJ
  • Kostenko, Lyudmila
  • Borg, Natalie A
  • Williamson, Nicholas A
  • Beddoe, Travis
  • Purcell, Anthony W
  • Burrows, Scott R
  • McCluskey, James
  • Rossjohn, Jamie

publication date

  • March 2007