Adaptability of the semi-invariant natural killer T-cell receptor towards structurally diverse CD1d-restricted ligands

EMBO J. 2009 Nov 18;28(22):3579-90. doi: 10.1038/emboj.2009.286. Epub 2009 Oct 8.

Abstract

The semi-invariant natural killer (NK) T-cell receptor (NKTcr) recognises structurally diverse glycolipid antigens presented by the monomorphic CD1d molecule. While the alpha-chain of the NKTcr is invariant, the beta-chain is more diverse, but how this diversity enables the NKTcr to recognise diverse antigens, such as an alpha-linked monosaccharide (alpha-galactosylceramide and alpha-galactosyldiacylglycerol) and the beta-linked trisaccharide (isoglobotriaosylceramide), is unclear. We demonstrate here that NKTcrs, which varied in their beta-chain usage, recognised diverse glycolipid antigens with a similar binding mode on CD1d. Nevertheless, the NKTcrs recognised distinct epitopic sites within these antigens, including alpha-galactosylceramide, the structurally similar alpha-galactosyldiacylglycerol and the very distinct isoglobotriaosylceramide. We also show that the relative roles of the CDR loops within the NKTcr beta-chain varied as a function of the antigen. Thus, while NKTcrs characteristically use a conserved docking mode, the NKTcr beta-chain allows these cells to recognise unique aspects of structurally diverse CD1d-restricted ligands.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptation, Biological / immunology
  • Animals
  • Antigen Presentation / immunology
  • Antigens, CD1d / chemistry
  • Antigens, CD1d / immunology*
  • Antigens, CD1d / metabolism*
  • Antigens, Tumor-Associated, Carbohydrate / immunology
  • Cells, Cultured
  • Galactosylceramides / chemistry
  • Galactosylceramides / immunology
  • Ligands
  • Lymphocyte Activation / immunology
  • Mice
  • Mice, Inbred C57BL
  • Models, Molecular
  • Natural Killer T-Cells / metabolism*
  • Receptors, Antigen, T-Cell / chemistry
  • Receptors, Antigen, T-Cell / immunology
  • Receptors, Antigen, T-Cell / metabolism*
  • Receptors, Antigen, T-Cell, alpha-beta / immunology
  • Receptors, Antigen, T-Cell, alpha-beta / metabolism
  • Structure-Activity Relationship
  • T-Cell Antigen Receptor Specificity / immunology

Substances

  • Antigens, CD1d
  • Antigens, Tumor-Associated, Carbohydrate
  • Galactosylceramides
  • Gb3 antigen
  • Ligands
  • Receptors, Antigen, T-Cell
  • Receptors, Antigen, T-Cell, alpha-beta
  • alpha-galactosylceramide