Lysophospholipid presentation by CD1d and recognition by a human Natural Killer T-cell receptor

EMBO J. 2012 Apr 18;31(8):2047-59. doi: 10.1038/emboj.2012.54. Epub 2012 Mar 6.

Abstract

Invariant Natural Killer T (iNKT) cells use highly restricted αβ T cell receptors (TCRs) to probe the repertoire of lipids presented by CD1d molecules. Here, we describe our studies of lysophosphatidylcholine (LPC) presentation by human CD1d and its recognition by a native, LPC-specific iNKT TCR. Human CD1d presenting LPC adopts an altered conformation from that of CD1d presenting glycolipid antigens, with a shifted α1 helix resulting in an open A' pocket. Binding of the iNKT TCR requires a 7-Å displacement of the LPC headgroup but stabilizes the CD1d-LPC complex in a closed conformation. The iNKT TCR CDR loop footprint on CD1d-LPC is anchored by the conserved positioning of the CDR3α loop, whereas the remaining CDR loops are shifted, due in part to amino-acid differences in the CDR3β and Jβ segment used by this iNKT TCR. These findings provide insight into how lysophospholipids are presented by human CD1d molecules and how this complex is recognized by some, but not all, human iNKT cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigen Presentation*
  • Antigens, CD1d / immunology
  • Antigens, CD1d / metabolism*
  • Crystallography, X-Ray
  • Humans
  • Lysophospholipids / immunology
  • Lysophospholipids / metabolism*
  • Models, Molecular
  • Natural Killer T-Cells / immunology*
  • Protein Conformation
  • Receptors, Antigen, T-Cell / immunology
  • Receptors, Antigen, T-Cell / metabolism*

Substances

  • Antigens, CD1d
  • CD1D protein, human
  • Lysophospholipids
  • Receptors, Antigen, T-Cell

Associated data

  • PDB/3TYF
  • PDB/3TZV
  • PDB/3U0P