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Title: Ovol1/2 loss‐induced epidermal defects elicit skin immune activation and alter global metabolism
Abstract

Skin epidermis constitutes the outer permeability barrier that protects the body from dehydration, heat loss, and myriad external assaults. Mechanisms that maintain barrier integrity in constantly challenged adult skin and how epidermal dysregulation shapes the local immune microenvironment and whole‐body metabolism remain poorly understood. Here, we demonstrate that inducible and simultaneous ablation of transcription factor‐encodingOvol1andOvol2in adult epidermis results in barrier dysregulation through impacting epithelial‐mesenchymal plasticity and inflammatory gene expression. We find that aberrant skin immune activation then ensues, featuring Langerhans cell mobilization and T cell responses, and leading to elevated levels of secreted inflammatory factors in circulation. Finally, we identify failure to gain body weight and accumulate body fat as long‐term consequences of epidermal‐specificOvol1/2loss and show that these global metabolic changes along with the skin barrier/immune defects are partially rescued by immunosuppressant dexamethasone. Collectively, our study reveals key regulators of adult barrier maintenance and suggests a causal connection between epidermal dysregulation and whole‐body metabolism that is in part mediated through aberrant immune activation.

 
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Award ID(s):
1763272
PAR ID:
10503811
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
EMBO reports
Date Published:
Journal Name:
EMBO reports
Volume:
24
Issue:
7
ISSN:
1469-221X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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