title: Resident macrophages in the healthy and inflamed intestinal muscularis externa.
abstract: Macrophages reside in a dense cellular network in the intestinal muscularis externa, and there is emerging evidence that the functionality of these cells determines the local microenvironment. Inflammatory responses during intestinal diseases change the homeostatic functionality of these cells causing inflammation and intestinal dysmotility. Such disturbances are not only induced by a change in the cellular composition in the intestinal muscularis but also by an altered crosstalk with the peripheral and central nervous system. In this review, we summarize the role of muscularis macrophages in the intestine in homeostasis and inflammation. We compare the functionality, the phenotype, and the origin of muscularis macrophages to their neighboring counterparts within the different layers of the intestine. We outline the cellular crosstalk with the enteric and the peripheral nervous system and summarize the current therapeutic approaches to modulate the functionality of these phagocytes.
authors.affiliation: Department of Surgery/Immune Pathophysiology, University of Bonn, 53121, Bonn, Germany. sven.wehner@ukbonn.de.
authors.forename: Sven
authors.identifier: 0000-0002-8632-7631
authors.initials: S
authors.lastname: Wehner
authors.affiliation: Institute for Experimental Immunology and Imaging, Department of Immunodynamics, University Duisburg-Essen and University Hospital Essen, 45147, Essen, Germany. engel@immunodynamics.de.
authors.forename: Daniel Robert
authors.identifier: 0000-0001-7301-353X
authors.initials: DR
authors.lastname: Engel
mesh_terms: D000818:Animals; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D007249:Inflammation / Q000473:pathology*; D007422:Intestines / Q000473:pathology* / Q000502:physiology*; D008264:Macrophages / Q000473:pathology* / Q000502:physiology*; D009130:Muscle, Smooth / Q000473:pathology / Q000502:physiology
keywords: Dendritic cell; Enteric nervous system; Intestinal muscularis externa; Macrophage; Peripheral nervous system