Pivotal role for skin trans-endothelial radio-resistant anti-inflammatory macrophages in tissue repair
- Harvard Medical School, United States
- Centro Nacional de Investigaciones Cardiovasculares, Spain
- Max Planck Institute of Molecular Biomedicine, Germany
Abstract
Heterogeneity and functional specialization among skin-resident macrophages are incompletely understood. In this study, we describe a novel subset of murine dermal perivascular macrophages that extend protrusions across the endothelial junctions in steady-state and capture blood-borne macromolecules. Unlike other skin-resident macrophages that are reconstituted by bone marrow-derived progenitors after a genotoxic insult, these cells are replenished by an extramedullary radio-resistant and UV-sensitive Bmi1+ progenitor. Furthermore, they possess a distinctive anti-inflammatory transcriptional profile, which cannot be polarized under inflammatory conditions, and are involved in repair and remodeling functions for which other skin-resident macrophages appear dispensable. Based on all their properties, we define these macrophages as Skin Transendothelial Radio-resistant Anti-inflammatory Macrophages (STREAM) and postulate that their preservation is important for skin homeostasis.
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Ethics
Animal experimentation: Animal studies were approved by the local ethics committee and by the Division of Animal Protection of Comunidad de Madrid (approved protocols PROEX 159/15 and 160/15). All animal procedures conformed to EU Directive 2010/63EU and Recommendation 2007/526/EC regarding the protection of animals used for experimental and other scientific purposes, enforced in Spanish law under Real Decreto 1201/2005
Copyright
© 2016, Barreiro et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Pivotal role for skin trans-endothelial radio-resistant anti-inflammatory macrophages in tissue repair
eLife 5:e15251.
https://doi.org/10.7554/eLife.15251
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