Mechanisms governing the physiologic regulation of cell fate: Hypoxia-induced differentiation of neuroendocrine cells from stem cells

细胞命运生理调控机制：缺氧诱导神经内分泌细胞从干细胞分化

基本信息

批准号：
10633171
负责人：
JAYARAJ RAJAGOPAL
金额：
$ 59.82万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-01 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10633171
关键词：
Ablation Address Apoptosis Asthma Attention Biology Blood flow Bronchopulmonary Dysplasia Cell Compartmentation Cell Death Cell Differentiation process Cell Fate Control Cell secretion Cells Characteristics Childhood Chronic Obstructive Pulmonary Disease Congenital diaphragmatic hernia Coupled Cystic Fibrosis Cytoprotection Data Diameter Disease Epithelial Cells Epithelium Esthesia Genes Genetic Goals Heterogeneity Human Hyperplasia Hypoxia Image Inflammation Injury Lung Lung diseases Maintenance Mediating Modeling Molecular Mus Neuroendocrine Cell Neuroepithelial Bodies Neuropeptides Neurosecretory Systems Oxygen Pathologic Pathway interactions Patients Peptides Photons Physiological Pneumonia Population Pulmonary Hypertension Regenerative response Regulation Research Respiratory Disease Role Series Signal Transduction Sudden infant death syndrome System Testing Tissues Tracheal Epithelium airway epithelium cell type epithelial injury human model in vivo infancy injury and repair lung injury mechanotransduction mouse model neuroendocrine differentiation normoxia novel prevent respiratory respiratory imaging response response to injury restoration stem cell differentiation stem cell proliferation stem cells

项目摘要

Project Summary Decades of studies have suggested that pulmonary neuroendocrine cells perform multiple functions including oxygen sensing, mechanotransduction, regulation of pulmonary blood flow, regulation of airway diameter, chemosensation, and most recently the regulation of inflammation. Additionally, increased NE cell abundance has been documented in several respiratory diseases including pulmonary hypertension, neuroendocrine hyperplasia of infancy (NEHI), sudden infant death syndrome, asthma, bronchopulmonary dysplasia, congenital pneumonia, cystic fibrosis, COPD, and congenital diaphragmatic hernia. However, it remains unclear whether these NE cells are a cause of disease or whether they represent a protective regenerative response to injury. Prior research has largely been conducted on neuroendocrine bodies (NEBs) which are clustered NE cells occurring at airway branch points. Herein, we focus on the role of solitary neuroendocrine cells which may represent a distinct population of NE cells that, like NEBs, are increased in diseases associated with NE cell hyperplasia. We provide evidence that hypoxia, frequently encountered in severe lung disease, stimulates neuroendocrine differentiation as a protective response. Using lineage tracing, we will test whether hypoxia-induced NE cells are plastic and capable of differentiating into other cell types following injury. We will also assess whether NE cell hyperplasia is reversible following the restoration of normoxia using a novel airway explant system coupled to long term 2 photon imaging. We hypothesize that hypoxia-dependent neuroendocrine differentiation is mediated through the HIF signaling cascade localized to the basal stem cell compartment, and will test whether airway stem cells possess this oxygen sensing machinery which in turn is responsible for triggering the onset of NE cell differentiation. We will further examine whether HIF signaling independent of hypoxia is required for the normal maintenance of tissue resident NE cells. Using genetic cell ablation, we will assess the functional relevance of hypoxia-induced neuroendocrine differentiation in injury models. We will then test whether the abundant peptide CGRP is a protective neuropeptide that ameliorates hypoxia-induced epithelial injury by promoting progenitor cell proliferation and preventing cell death. To address NE cell heterogeneity, we have identified Tuj1 as an epithelial marker of solitary NE cells that is absent in NEBs. We show that hyperplastic NE cells in Neuroendocrine Hyperplasia of Infancy (NEHI) are positive for this marker. Lastly, we will establish a system for studying human primary airway stem cell differentiation into Tuj1+ solitary NE cells following hypoxia.

项目概要数十年的研究表明，肺神经内分泌细胞具有多种功能，包括氧传感、机械传导、肺血流调节、气道直径调节、化学感觉，以及最近的炎症调节。此外，NE细胞丰度增加已被记录在多种呼吸系统疾病中，包括肺动脉高压、神经内分泌疾病婴儿期增生（NEHI）、婴儿猝死综合症、哮喘、支气管肺发育不良、先天性肺炎、囊性纤维化、慢性阻塞性肺病和先天性膈疝。但目前尚不清楚是否这些 NE 细胞是否是疾病的原因，或者它们是否代表对损伤的保护性再生反应。先前的研究主要针对神经内分泌体（NEB）进行，神经内分泌体是簇状的 NE 细胞发生在气道分支点。在此，我们重点关注孤立神经内分泌细胞的作用，这可能代表一个独特的 NE 细胞群，与 NEB 一样，它们在与 NE 细胞相关的疾病中增加增生。我们提供的证据表明，严重肺部疾病中经常遇到的缺氧会刺激神经内分泌分化作为一种保护性反应。使用谱系追踪，我们将测试缺氧诱导的 NE 细胞是否塑料并且能够在受伤后分化成其他细胞类型。我们还将评估 NE 细胞是否使用新型气道外植体系统恢复正常氧浓度后，增生是可逆的长期 2 光子成像。我们假设缺氧依赖性神经内分泌分化是介导的通过定位于基底干细胞区室的 HIF 信号级联，并测试气道是否干细胞拥有这种氧气感应机制，进而负责触发 NE 细胞的发生差异化。我们将进一步研究独立于缺氧的 HIF 信号传导是否是正常细胞所必需的。维持组织驻留 NE 细胞。使用遗传细胞消融，我们将评估以下功能的相关性：损伤模型中缺氧诱导的神经内分泌分化。然后我们将测试丰富的肽是否 CGRP 是一种保护性神经肽，通过促进祖细胞生成来改善缺氧引起的上皮损伤细胞增殖并防止细胞死亡。为了解决 NE 细胞异质性，我们将 Tuj1 确定为 NEB 中不存在的孤立 NE 细胞的上皮标记。我们发现，增生性 NE 细胞婴儿神经内分泌增生症 (NEHI) 对该标记物呈阳性。最后，我们将建立一个系统研究缺氧后人类原代气道干细胞分化为 Tuj1+ 孤立 NE 细胞。