Impact of alcohol exposure on unjamming the airway epithelium

项目摘要 在美国，酒精使用障碍每年影响1400多万成年人，导致8.8万人死亡。 长期饮酒会显著增加人们患肺部感染和急性呼吸道感染的风险 窘迫综合征(ARDS)。这种对损伤的敏感性增加的情况被称为酒精性肺综合征， 它是由肺免疫系统和肺泡上皮屏障功能障碍引起的。然而，人们对此知之甚少 关于酒精如何影响传导呼吸道的上皮细胞，即气管和支气管，这是 抵御肺部感染病原体的第一道防线。我们已经使用了原代呼吸道上皮细胞 从健康和酗酒患者中分离并在体外分化，以检测酒精对 细胞屏障功能和形态。健康分化的原代呼吸道上皮细胞呈鹅卵石状- 喜欢模式，一旦单层成熟就变得不动--这是一种正常的呼吸道细胞表型，称为 “干扰”。相比之下，从慢性酒精中毒患者中分离的呼吸道上皮细胞仍可迁移，并且在 “无堵塞”状态，因为在单层中出现了拉伸的细胞区域和漩涡的细胞。此外，Rate 在乙醇存在下体外培养和分化的气管细胞保持畅通，而对照组 单层膜变得堵塞。已知跨膜蛋白连接黏附分子A(JAM-A)是一种重要的细胞因子。 A)调节上皮细胞迁移，并通过控制细胞旁流动调节屏障功能。 小分子作为紧密连接复合体的一部分。最近，我们发现大鼠和人在体外都有 长期酒精暴露的分化模型降低了JAM-A在RNA和蛋白质中的表达 与对照组相比，其水平和屏障功能降低。尽管如此，长期酗酒 暴露降低JAM-A的表达并影响呼吸道上皮屏障功能和迁移 完全阐明了。已知长期酒精暴露会激活转化生长因子-β1，最近的证据表明转化生长因子-β1与 为了压抑JAM-A的表达。因此，我们假设长期饮酒的有害影响 由于转化生长因子-β-1的激活导致JAM-1的减弱，从而暴露在传导的呼吸道上皮细胞上。 一个表情和随后的疏通。我的研究计划是为了确定长期饮酒 暴露(可能通过转化生长因子-β1)影响JAM-A的表达，从而影响原发疾病的屏障功能 目标1)，并确定JAM-A如何调节集体细胞迁移/细胞堵塞(目标2)。 这个项目的目标是确定慢性酒精暴露导致屏障的目标途径 传导呼吸道上皮细胞的功能和细胞迁移缺陷。

PROJECT ABSTRACT Alcohol use disorder affects over 14 million adults and causes 88,000 deaths each year in the United States. Chronic alcohol use significantly increases people’s risk of developing lung infections and acute respiratory distress syndrome (ARDS). This increased sensitivity to injury is a condition known as alcoholic lung syndrome, and it is caused by dysfunction of the lung immune system and alveolar epithelial barrier. However, little is known about how alcohol impacts epithelial cells in the conducting airway, i.e. the trachea and bronchi, which are the first line of defense against infectious pathogens in the lungs. We have used primary airway epithelial cells isolated from healthy and alcoholic patients and differentiated them in vitro to examine the impact of alcohol on cell barrier function and morphology. Healthy differentiated primary airway epithelial cells exhibit a cobblestone- like pattern and become immobile once the monolayer has matured— a normal airway cell phenotype known as “jamming”. By contrast, airway epithelial cells isolated from chronic alcoholics remained migratory and in an “unjammed” state, since areas of stretched cells and swirls of cells appear in the monolayer. Additionally, rat tracheal cells grown and differentiated in vitro in the presence of ethanol remain unjammed while control monolayers become jammed. It is known that the transmembrane protein junctional adhesion molecule A (JAM- A) regulates epithelial cell migration, and it also regulates barrier function by controlling the paracellular flow of small molecules as part of tight junction complexes. Recently, we found that both rat and human in vitro differentiation models chronically exposed to alcohol have decreased JAM-A expression at both RNA and protein levels and decreased barrier function compared to their control counterparts. Nevertheless, how chronic alcohol exposure decreases JAM-A expression and impacts airway epithelial barrier function and migration has not been fully elucidated. Chronic alcohol exposure is known to activate TGF-β1 and recent evidence has linked TGF-β1 to repression of JAM-A expression. Thus, we hypothesize that the deleterious effects of chronic alcohol exposure on conducting airway epithelial cells are due to TGF-β1 activation causing attenuation of JAM- A expression and subsequent unjamming. My research plan is designed to determine how chronic alcohol exposure (potentially through TGF-β1) impacts JAM-A expression and, therefore, barrier function in primary airway epithelial cells (Aim 1), and to define how JAM-A regulates collective cell migration/cell jamming (Aim 2). The goal of this project is to identify targetable pathways by which chronic alcohol exposure causes barrier function and cell migration defects in conducting airway epithelial cells.