title: Identification and putative roles of distinct subtypes of intestinal dendritic cells in neuroimmune communication: what can be learned from other organ systems?
abstract: The gastrointestinal (GI) tract, just like the skin and the airways, is constantly exposed to both harmless and pathogenic organisms and hence requires a tightly regulated immune homeostasis to function properly. A central role in the regulation of this balance is played by the dendritic cells (DCs), a heterogeneous population of antigen-presenting cells that can be further divided into distinct subsets with different functions depending on the tissue they reside in. In recent years, the DC population in the lamina propria (LP) of the intestine has emerged as a key player in immune surveillance. Given the extensive innervation of the GI mucosa, these DC subsets possibly are also regulated by interactions with neuronal components. Current knowledge, be it still fragmentary, indicates that dysregulation of this neuroimmune communication leads to the onset of pathological disorders. The present review article deals with the identification and interaction of distinct subtypes of mouse intestinal LP DCs with elements of the enteric nervous system (ENS) in normal and inflammatory conditions. Furthermore, the question is addressed whether any parallels can be drawn between intestinal LP DCs and DCs residing in the skin and lung in order to gain a better insight into common or clearly distinct mechanistic pathways and the possible impact of the mucosal components in the microenvironment. The exact way in which the ENS is serving its immunomodulatory roles in the GI tract is still largely unknown, although there are significant indications for a crosstalk between LP DCs and components of the ENS. This review clearly shows that in the three different organ systems the same neurotransmitters (i.e., SP, CGRP, and VIP) reoccur, serving similar functions. Mechanistic lessons learned from other organ systems, such as the skin and lung, may be of substantial help in further exploring the nature of the neuroimmune communication between GI innervation and LP DCs.
authors: Laboratory of Cell biology and Histology, Department of Veterinary Sciences, University of Antwerp, Antwerp, Belgium.
authors: Katrien
authors: K
authors: Alpaerts
authors: Roeland
authors: R
authors: Buckinx
authors: Dirk
authors: D
authors: Adriaensen
authors: Luc
authors: L
authors: Van Nassauw
authors: Jean-Pierre
authors: JP
authors: Timmermans
mesh_terms: D000818:Animals; D002450:Cell Communication / Q000502:physiology*; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology; D017615:Enteric Nervous System / Q000276:immunology; D006801:Humans; D007422:Intestines / Q000166:cytology* / Q000276:immunology; D015213:Neuroimmunomodulation / Q000502:physiology*
keywords: dendritic cells; ileum; neuroimmune modulation; subtypes