Cross-presentation of oral antigens by liver sinusoidal endothelial cells leads to CD8 T cell tolerance

Eur J Immunol. 2005 Oct;35(10):2970-81. doi: 10.1002/eji.200526034.

Abstract

After ingestion, oral antigens distribute systemically and provoke T cell stimulation outside the gastrointestinal tract. Within the liver, scavenger liver sinusoidal endothelial cells (LSEC) eliminate blood-borne antigens and induce T cell tolerance. Here we investigated whether LSEC contribute to oral tolerance. Oral antigens were efficiently cross-presented on H-2K(b) by LSEC to naive CD8 T cells. Cross-presentation efficiency in LSEC but not dendritic cells was increased by antigen-exposure to heat or low pH. Mechanistically, cross-presentation in LSEC requires endosomal maturation, involves hsc73 and proteasomal degradation. H-2K(b)-restricted cross-presentation of oral antigens by LSEC in vivo induced CD8 T cell priming and led to development of CD8 T cell tolerance in two independent experimental systems. Adoptive transfer of LSEC from mice fed with antigen (ovalbumin) into RAG2-/- knockout mice, previously reconstituted with naive ovalbumin-specific CD8 T cells, prevented development of specific cytotoxicity and expression of IFN-gamma in CD8 T cells. Using a new transgenic mouse line expressing H-2K(b) only on endothelial cells, we have demonstrated that oral antigen administration leads to tolerance in H-2K(b)-restricted CD8 T cells. Collectively, our data demonstrate a participation of the liver, in particular scavenger LSEC, in development of CD8 T cell tolerance towards oral antigens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adoptive Transfer
  • Animals
  • Antigen Presentation / immunology
  • Antigens / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Cross-Priming / immunology*
  • Endothelial Cells / immunology*
  • Immune Tolerance / immunology*
  • Liver / cytology
  • Mice
  • Mice, Knockout

Substances

  • Antigens