Requirement for diverse, low-abundance peptides in positive selection of T cells Academic Article Article uri icon


MeSH Major

  • Cell Communication
  • Lymphocyte Activation
  • T-Lymphocytes, Helper-Inducer
  • T-Lymphocytes, Regulatory


  • Whether a single major histocompatibility complex (MHC)-bound peptide can drive the positive selection of large numbers of T cells has been a controversial issue. A diverse population of self peptides was shown to be essential for the in vivo development of CD4 T cells. Mice in which all but 5 percent of MHC class II molecules were bound by a single peptide had wild-type numbers of CD4 T cells. However, when the diversity within this 5 percent was lost, CD4 T cell development was impaired. Blocking the major peptide-MHC complex in thymus organ culture had no effect on T cell development, indicating that positive selection occurred on the diverse peptides present at low levels. This requirement for peptide diversity indicates that the interaction between self peptides and T cell receptors during positive selection is highly specific.

publication date

  • January 1999



  • Academic Article


Digital Object Identifier (DOI)

  • 10.1126/science.283.5398.67

PubMed ID

  • 9872742

Additional Document Info

start page

  • 67

end page

  • 70


  • 283


  • 5398