Molecular mechanisms of portal vein tolerance

Abstract

The liver has been considered as a tolerogenic organ in the sense that favors the induction of peripheral tolerance. The administration of antigens (Ags) via the portal vein causes tolerance, which is termed portal vein tolerance and can explain the occurrence of tolerogenic responses in the liver. Here we discuss the fundamental mechanisms accounting for portal vein tolerance. Antigen-presenting cells (APCs) in the liver, especially dendritic cells and sinusoidal endothelial cells, have limited the ability to produce pro-inflammatory cytokines upon stimulation with endotoxin, an effect that could be due to the continuous exposure to bacterial Ags derived from intestinal microflora. Ag presentation by liver APCs results in T cell tolerance through clonal deletion and selection of regulatory T cells. Thus, APCs with immunosuppressive functions are associated with the achievement of portal vein tolerance via the induction of clonal deletion and generation of regulatory T cells.

Genome Wide Analysis of Inbred Mouse Lines Identifies a Locus Containing Ppar-γ as Contributing to Enhanced Malaria Survival

“…This in return could result in tissue damage in various organs leading to early death. In contrast to the spleen, antigen presentation in the liver induces tolerance, known as portal vein tolerance [41]. Indeed, we observed that resistant mice had significantly higher luciferase expression in the liver than susceptible mice.…”

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The implications of myelodysplastic syndrome – associated chromosomal abnormalities in the development of graft‐versus‐host disease

“…The procedures are in accordance with the Helsinki Declaration of 1975. CD14 + monocytes (1 × 10 6 /mL) were isolated from PBMCs using CD14 microbeads (Miltenyi Biotec, Gladbach, Germany) and were cultured for 16 h in complete RPMI medium in the presence of peptidoglycan (PGN, 10 μg/mL, InvivoGen, San Diego, CA, USA) or lipopolysaccharide (LPS, 1 μg/mL, Sigma‐Aldrich, St. Louis, MO, USA) as previously described . Cells were stained with phycoerythrin (PE)‐conjugated CD14 antibody (eBioscience, San Diego, CA, USA).…”

“…Monocytes (1 × 10 6 /mL) were cultured for 16 h in complete RPMI medium in the presence of PGN (10 μg/mL) or LPS (1 μg/mL). Culture supernatants were subjected to enzyme‐linked immunosorbent assay (ELISA) for the measurement of tumor necrosis factor‐α (TNF‐α) and interleukin‐10 (IL‐10) (BD Bioscience) as described previously .…”