Analysis of Immunomodulatory Effects of Vitamin D in Epithelial-Mesenchymal Transition and Airway Remodeling in Allergic Airway Inflammation.
type: CreativeWork
description: The first line of defense from environmental factors in the host is the epithelium. In the lung, the epithelial layer provides not only a passive physical barrier, but also acts as an active protector through the release of antimicrobial agents, cytokines, and other factors which can activate the innate and adaptive immune system. Patients that suffer from asthma, a chronic inflammatory disease of the airways, show pathological changes in the airways, including airway remodeling, basement membrane thickening, and epithelial damage with large immune cell infiltrate. How the epithelium contributes to airway remodeling and subepithelial fibrosis is unknown. However, it has been proposed that in inflammatory conditions, epithelial cells can undergo modifications that contribute to the pathophysiology of asthma. Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells transition into a myofibroblast cell with enhanced migratory ability to secrete connective tissue. Vitamin D has been shown to have immunomodulatory properties in both innate and adaptive immunity. The relationship between asthma and vitamin D deficiency has been linked with increased asthma pathogenesis. The active form of vitamin D, calcitriol, exerts its actions through the vitamin D receptor (VDR) inducing a number of biological processes. To better understand the mechanisms underlying EMT and the nature of vitamin D modulation in the airway epithelium, human bronchial epithelial cells were stimulated with both calcitriol and transforming growth factor (TGF)-β1 or TGF-β2. These cells were analyzed for their expression of EMT markers and their functional invasive and migratory properties. Both TGF-β1 and TGF-β2 increased the expression of EMT markers, Snail, N-cadherin, and vimentin, and decreased the expression of E-cadherin. Calcitriol inhibited the effect of both TGF-β1 and TGF-β2 on the expression of EMT markers. Calcitriol also prevented the migratory and invasive actions of th…
abstract: The first line of defense from environmental factors in the host is the epithelium. In the lung, the epithelial layer provides not only a passive physical barrier, but also acts as an active protector through the release of antimicrobial agents, cytokines, and other factors which can activate the innate and adaptive immune system. Patients that suffer from asthma, a chronic inflammatory disease of the airways, show pathological changes in the airways, including airway remodeling, basement membrane thickening, and epithelial damage with large immune cell infiltrate. How the epithelium contributes to airway remodeling and subepithelial fibrosis is unknown. However, it has been proposed that in inflammatory conditions, epithelial cells can undergo modifications that contribute to the pathophysiology of asthma. Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells transition into a myofibroblast cell with enhanced migratory ability to secrete connective tissue. Vitamin D has been shown to have immunomodulatory properties in both innate and adaptive immunity. The relationship between asthma and vitamin D deficiency has been linked with increased asthma pathogenesis. The active form of vitamin D, calcitriol, exerts its actions through the vitamin D receptor (VDR) inducing a number of biological processes. To better understand the mechanisms underlying EMT and the nature of vitamin D modulation in the airway epithelium, human bronchial epithelial cells were stimulated with both calcitriol and transforming growth factor (TGF)-β1 or TGF-β2. These cells were analyzed for their expression of EMT markers and their functional invasive and migratory properties. Both TGF-β1 and TGF-β2 increased the expression of EMT markers, Snail, N-cadherin, and vimentin, and decreased the expression of E-cadherin. Calcitriol inhibited the effect of both TGF-β1 and TGF-β2 on the expression of EMT markers. Calcitriol also prevented the migratory and invasive actions of th…
author: Fischer, Kimberly D.
language: en_US
date published: 2015-08-03
date modified: 2026-07-24T01:51:19Z
provider: Creighton University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Creighton University

PropertyValue
property ID: Handle
value: http://hdl.handle.net/10504/71335