Autophagy and esophageal tissue remodeling in EoE

EoE 中的自噬和食管组织重塑

基本信息

批准号：
10298488
负责人：
Hiroshi Nakagawa
金额：
$ 48.21万
依托单位：
COLUMBIA UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-18 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10298488
关键词：
3-Dimensional Affect Antioxidants Autophagocytosis Basal Cell Basal Cell Hyperplasia Biology Biopsy CRISPR/Cas technology Cell Fate Control Cell Lineage Cells Cellular Stress Response Cellular biology Chronic Clinical Clonal Expansion Coupled Data Defect Defense Mechanisms Desmosomes Development Disease Dose Down-Regulation Drug Targeting Eosinophilic Esophagitis Epithelial Esophageal Diseases Esophageal Stenosis Esophageal Tissue Esophagitis Esophagus Event Fibrosis Flow Cytometry Genetic Genetically Engineered Mouse Growth Homeostasis Human Immune Impairment Infiltration Inflammation Inflammatory Interleukin-13 Knowledge Label Laboratories Lamina Propria Link Mediating Mediator of activation protein Microscopy Mission Mitochondria Mitochondrial DNA Mitotic Modeling Mucous Membrane Mus Nature Organoids Oxidative Stress Pathogenesis Patients Peptic Esophagitis Pharmacology Proteins Public Health Publications Quality of life Radiation Reactive Oxygen Species Research Role Signal Transduction Squamous Epithelium Stratified Squamous Epithelium Structure Tamoxifen Testing Tight Junctions Tissues United States National Institutes of Health Validation base cytokine drug testing experimental study food allergen human disease inflammatory milieu innovation insight keratinocyte mitochondrial autophagy mouse model notch protein novel self-renewal stress reactivity

项目摘要

Project summary Esophageal stratified squamous epithelia comprise proliferative basal cells that undergo terminal differentiation in the suprabasal cell layer. This homeostatic proliferation-differentiation gradient is regulated by Notch signaling that is impaired in eosinophilic esophagitis (EoE), a chronic inflammatory disorder characterized by mucosal eosinophilic infiltration, basal cell hyperplasia (BCH) and subepithelial fibrosis. BCH contributes to a barrier defect that facilitates lamina propria remodeling, culminating in fibrotic esophageal strictures that severely affect patients’ quality of life. While food allergen-activated immune cells and cytokines mediate EoE pathogenesis, the relationship between esophageal epithelial biology and EoE pathogenesis remains elusive. The ongoing project (R01-114436) has established the role of autophagy, a highly conserved cellular stress response, as a fundamental mucosal defense mechanism in EoE. Epithelial autophagy activation involves mitochondrial stress and reactive oxygen species (ROS) induced by proinflammatory EoE-relevant cytokines such as IL-13, which in turn stimulate BCH. BCH features depletion of CD73+ basal cells and reciprocal expansion of CD73- cells with low Notch activity, thereby limiting terminal differentiation. IL-13 promotes BCH by inhibiting Notch while inducing ROS-mediated mitochondrial (mt) damage marked by mtDNA depletion. Moreover, CD73- cells may maintain BCH via Notch-independent epithelial renewal. The overall objective in this competing renewal application is to elucidate the nature of basal cell fate regulation in EoE pathogenesis. The central hypothesis is that EoE-related inflammation influences basal cells’ activity to promote esophageal tissue remodeling. This hypothesis has been formulated based upon strong preliminary data and publications from the applicant’s laboratory and will be pursued through the following interrelated Specific Aims: (1) To elucidate how autophagy activation limits BCH in the EoE inflammatory milieu; (2) To delineate the role of mitochondrial damage in EoE-related BCH; (3) To unravel how Notch signaling protects against tissue remodeling in EoE. The present proposal utilizes a robust murine model of EoE with squamous epithelia- specific autophagy impairment, mtDNA depletion, or Notch inhibition with concurrent basal cell lineage tracing. These approaches are coupled with ex vivo esophageal 3D organoids from EoE mice and patient biopsies to define the mechanistic and functional role of autophagy and mitochondria in basal cell homeostasis. These innovative studies will reveal novel insights into esophageal basal cell biology and tissue remodeling. With genetically engineered mice, 3D organoids and patient biopsies, we will build a comprehensive platform for the development and validation of novel translational applications related to EoE therapy (autophagy activation and mitochondria-targeted antioxidants). These findings may have direct clinical impact in EoE, and potentially other diseases (e.g. GERD) where autophagy, epithelial barrier defects and fibrosis have been implicated.

项目摘要食管分层的鳞状上皮完全增殖的基本细胞，经历末端分化在上胸腔细胞层中。这种稳态增殖 - 分化梯度由Notch调节在嗜酸性脂肪炎（EOE）中受损的信号传导，这是一种慢性炎症性疾病粘膜嗜酸性浸润，碱性细胞增生（BCH）和上皮下纤维化。 BCH有助于促进固定层的屏障缺陷，达到纤维化食管狭窄的最终严重影响患者的生活质量。食物过敏原激活的免疫细胞和细胞因子介导EOE 发病机理，食管上皮生物学与EOE发病机理之间的关系仍然难以捉摸。正在进行的项目（R01-114436）已经确定了自噬的作用，自噬是一种高度保守的细胞应激反应，作为EOE中的基本粘膜防御机制。上皮自噬激活涉及促炎性EOE相关细胞因子诱导的线粒体应激和活性氧（ROS）例如IL-13，进而刺激BCH。 BCH具有CD73+基本单元和倒数的部署 CD73-细胞具有低凹槽活性的扩展，从而限制了末端分化。 IL-13促进了BCH 通过抑制缺口，同时诱导ROS介导的线粒体（MT）损伤，该损伤标记为mtDNA耗竭。此外，CD73-细胞可以通过独立于缺口的上皮更新来维持BCH。总体目标这种竞争性更新应用是为了阐明EOE发病机理中基本细胞脂肪调节的性质。中心假设是EOE相关的炎症会影响基本细胞的活性以促进食管组织重塑。该假设是根据强大的初步数据和出版物提出的从申请人的实验室中，将通过以下相互关联的特定目的来追求：（1）阐明自噬激活如何限制EOE炎症环境中的BCH；（2）描述 EOE相关BCH中的线粒体损伤；（3）解开Notch信号如何防止组织在EOE中进行改建。本提案使用正方形上皮的EOE的强大鼠模型特定的自噬损伤，mtDNA耗竭或并发基本细胞谱系抑制作用。这些方法与来自EOE小鼠和患者活检的外体食管3D器官结合到定义自噬和线粒体在碱性细胞稳态中的机械和功能作用。这些创新研究将揭示对食道基本细胞生物学和组织重塑的新见解。和基因工程的小鼠，3D类器官和患者活检，我们将建立一个全面的平台与EOE治疗有关的新型翻译应用的开发和验证（自噬激活）和线粒体靶向的抗氧化剂）。这些发现可能对EOE产生直接的临床影响，并有可能其他疾病（例如GERD）涉及自噬，上皮屏障缺陷和纤维化。