Self-encounters of the third kind: lymph node stroma promotes tolerance to peripheral tissue antigens

Mucosal Immunol. 2008 Jul;1(4):248-51. doi: 10.1038/mi.2008.19. Epub 2008 May 14.

Abstract

Multiple mechanisms have evolved to maintain tolerance among CD8(+) T cells to innocuous antigens that arise in cutaneous and mucosal tissues. In the thymus, medullary thymic epithelial cells directly present peripheral tissue antigens (PTAs) and incite the deletion of self-reactive thymocytes. Cross-presentation of PTAs by functionally immature, CD8alpha(+) dendritic cells can lead to the deletion of self-reactive CD8(+) T cells in secondary lymphoid organs. A third mechanism of deletional tolerance has recently been uncovered in which lymph node-resident stromal cells of non-hematopoietic origin present endogenously expressed PTAs to circulating CD8(+) T cells. Emerging data suggest that lymph node stroma is a unique niche for controlling self-reactive T cells.

MeSH terms

  • Animals
  • Antigen Presentation / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Humans
  • Immune Tolerance*
  • Lymph Nodes / immunology*
  • Stromal Cells / immunology
  • Thymus Gland / immunology