Generating intrathymic microenvironments to establish T-cell tolerance

Nat Rev Immunol. 2007 Dec;7(12):954-63. doi: 10.1038/nri2187.


Alphabeta T cells pass through a series of lymphoid tissue stromal microenvironments to acquire self tolerance and functional competence. In the thymus, positive selection of the developing T-cell receptor repertoire occurs in the cortex, whereas events in the medulla purge the system of self reactivity. T cells that survive are exported to secondary lymphoid organs where they direct first primary and then memory immune responses. This Review focuses on the microenvironments that nurture T-cell development rather than on T cells themselves. We summarize current knowledge on the formation of thymic epithelial-cell microenvironments, and highlight similarities between the environments that produce T cells and those that select and maintain them during immune responses.

Publication types

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

MeSH terms

  • Animals
  • Cell Proliferation
  • Epithelial Cells / physiology*
  • Humans
  • Immune Tolerance*
  • Stem Cells / physiology
  • T-Lymphocytes / immunology*
  • T-Lymphocytes, Helper-Inducer / physiology
  • Thymus Gland / cytology*