Three-dimensional structure of a human class II histocompatibility molecule complexed with superantigen

Nature. 1994 Apr 21;368(6473):711-8. doi: 10.1038/368711a0.


The structure of a bacterial superantigen, Staphylococcus aureus enterotoxin B, bound to a human class II histocompatibility complex molecule (HLA-DR1) has been determined by X-ray crystallography. The superantigen binds as an intact protein outside the conventional peptide antigen-binding site of the class II major histocompatibility complex (MHC) molecule. No large conformational changes occur upon complex formation in either the DR1 or the enterotoxin B molecules. The structure of the complex helps explain how different class II molecules and superantigens associate and suggests a model for ternary complex formation with the T-cell antigen receptor (TCR), in which unconventional TCR-MHC contacts are possible.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Crystallography, X-Ray
  • Enterotoxins / chemistry*
  • Enterotoxins / immunology
  • HLA-DR1 Antigen / chemistry*
  • Humans
  • Macromolecular Substances
  • Mice
  • Models, Molecular
  • Molecular Sequence Data
  • Receptors, Antigen, T-Cell / metabolism
  • Staphylococcus aureus / immunology
  • Superantigens / chemistry*
  • Superantigens / immunology


  • Enterotoxins
  • HLA-DR1 Antigen
  • Macromolecular Substances
  • Receptors, Antigen, T-Cell
  • Superantigens
  • enterotoxin B, staphylococcal