IL-10-dependent partial refractoriness to Toll-like receptor stimulation modulates gut mucosal dendritic cell function

Monteleone, I., Platt, A., Jaensson, E., Agace, W. and Mowat, A. (2008) IL-10-dependent partial refractoriness to Toll-like receptor stimulation modulates gut mucosal dendritic cell function. European Journal of Immunology, 38(6), pp. 1533-1547. (doi: 10.1002/eji.200737909)

Abstract

The default response of the intestinal immune system to most antigens is the induction of immunological tolerance, which is difficult to reconcile with the constant exposure to ligands for TLR and other pattern recognition receptors. We showed previously that dendritic cells (DC) from the lamina propria of normal mouse intestine may be inherently tolerogenic and here we have explored how this might relate to the expression and function of Toll-like receptors (TLR). Lamina propria (LP) DC showed higher levels of TLR 2, 3, 4 and 9 protein expression than spleen and MLN DC, with most TLR-expressing DC in the gut being CD11clo, class II MHClo, CD103–, CD11b– and F4/80–. TLR expression by lamina propria DC was low in the upper small intestine and higher in distal small intestine and colon. Freshly isolated lamina propria DC expressed some CD40, CD80, CD86 and functional CCR7. These were up-regulated on CD11clo, but not on CD11chi LP DC by stimulation via TLR. However, there was little induction of IL-12 by either subset in response to TLR ligation. This was associated with constitutive IL-10 production and was reversed by blocking IL-10 function. Thus, IL-10 may maintain LP DC in a partially unresponsive state to TLR ligation, allowing them to have a critical role in immune homeostasis in the gut.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Platt, Dr Andrew and Mowat, Professor Allan
• Authors: Monteleone, I., Platt, A., Jaensson, E., Agace, W., and Mowat, A.
• College/School: College of Medical Veterinary and Life Sciences; College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: European Journal of Immunology
• ISSN: 0014-2980