The relationship of MHC-peptide binding and T cell activation probed using chemically defined MHC class II oligomers

Immunity. 2000 Mar;12(3):241-50. doi: 10.1016/s1074-7613(00)80177-6.


A series of novel chemically defined soluble oligomers of the human MHC class II protein HLA-DR1 was constructed to probe the molecular requirements for initiation of T cell activation. MHC dimers, trimers, and tetramers stimulated T cells, as measured by upregulation of the activation markers CD69 and CD25, and by internalization of activated T cell receptor subunits. Monomeric MHC-peptide complexes engaged T cell receptors but did not induce activation. For a given amount of receptor engagement, the extent of activation was equivalent for each of the oligomers and correlated with the number of T cell receptor cross-links induced. These results suggest that formation or rearrangement of a T cell receptor dimer is necessary and sufficient for initiation of T cell signaling.

Publication types

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

MeSH terms

  • Biomarkers
  • CD3 Complex / immunology
  • CD4-Positive T-Lymphocytes / immunology*
  • Cell Line
  • HLA-DR1 Antigen / chemistry
  • HLA-DR1 Antigen / immunology*
  • HLA-DR1 Antigen / metabolism
  • Humans
  • Lymphocyte Activation / immunology*
  • Oligopeptides / immunology
  • Oligopeptides / metabolism
  • Receptors, Interleukin-2 / immunology
  • Signal Transduction


  • Biomarkers
  • CD3 Complex
  • HLA-DR1 Antigen
  • Oligopeptides
  • Receptors, Interleukin-2