COVID-19: Understanding The Role of Corona Virus InducedDisruption Of Alveolar Type 2 Cell Function And SurfactantHomeostasis In The Pathogenesis Of COVID-19 AcuteRespiratory Distress Syndrome

COVID-19：了解冠状病毒引起的肺泡 2 型细胞功能和表面活性剂稳态破坏在 COVID-19 急性呼吸窘迫综合征发病机制中的作用

• 批准号: 10744174
• 负责人: MICHAEL FRANCIS BEERS
• 金额: --
• 依托单位: PHILADELPHIA VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10744174
• 关键词: 2019-nCoV; ACE2; Acceleration; Acute Lung Injury; Acute Respiratory Distress Syndrome; Address; Affect; Alveolar; Anabolism; Apoptosis; Autophagocytosis; Behavior; Berlin; Big Data; Biochemistry; Bioenergetics; Biology; Biophysics; COVID-19; COVID-19 pandemic; COVID-19 pathogenesis; Caring; Catalogs; Cell Communication; Cell Ontogeny; Cell model; Cell physiology; Cells; Cellular Stress; Cellular biology; Characteristics; Cicatrix; Clinical; Coronavirus; Coronavirus Infections; Coupled; Data; Defect; Development; Disease; Dissociation; Distal; Distress; Economics; Epidemic; Epithelial Cells; Epithelium; Evaluation; Foundations; Functional disorder; Funding; Future; Genetic; Goals; Growth; Hand; Health; Homeostasis; Human; Hypoxemia; Hypoxemic Respiratory Failure; Impairment; In Vitro; Infection; Inflammatory; Innate Immune Response; International; Investigation; Knowledge; Lead; Link; Lung; Lung Capacity; Lung infections; Maintenance; Maps; Mediating; Metabolism; Middle East Respiratory Syndrome Coronavirus; Mitochondria; Modeling; Molecular; Molecular Target; Morbidity - disease rate; Motivation; Mus; Natural Immunity; Organ; Organoids; Outcome; Pathogenesis; Pathway interactions; Peripheral; Phenotype; Physiological; Population; Positioning Attribute; Pre-Clinical Model; Program Reviews; Proteins; Pulmonary Inflammation; Pulmonary Surfactants; Quality Control; Radiology Specialty; Reagent; Recovery; Recurrence; Refractory; Reporting; Research Design; Residual state; Respiratory Disease; Respiratory Failure; Respiratory Mechanics; Role; SARS coronavirus; SARS-CoV-2 infection; Scientist; Severities; Signal Pathway; Slice; Survivors; Syndrome; System; Techniques; Technology; Testing; Therapeutic; Translating; Ubiquitin; Veterans; Viral; Virus; Virus Diseases; Work; alveolar epithelium; arm; biological adaptation to stress; coronavirus pandemic; cytokine; effective therapy; endophenotype; endoplasmic reticulum stress; epithelial injury; epithelial repair; experience; fibrotic lung; immunopathology; improved; in vivo; induced pluripotent stem cell; lipid metabolism; lung injury; lung repair; mortality; mouse model; multicatalytic endopeptidase complex; new therapeutic target; novel; novel coronavirus; novel strategies; pandemic disease; pharmacologic; pre-clinical; progenitor; programs; protein kinase R; protein metabolism; receptor; repaired; respiratory; response; senescence; stem cell function; stem cells; surfactant; tool; transcriptomic profiling; transcriptomics; virology

ABSTRACT The Severe Acute Respiratory Syndrome (SARS)-associated coronavirus 2 (SCoV2) is the cause of COVID-19 syndrome which is marked by a refractory acute lung injury that results in dramatic hypoxic respiratory failure and high mortality. Despite the recurrent health and economic devastation produced by novel coronaviruses (nCoV) over the past 20 years including SCoV2 as well as its predecessors SCoV1, and MERS-CoV, there remains a significant unmet need both for a clearer understanding of virus-host cell interactions as well as identification of new therapeutic targets. To address these issues with the ultimate goal of improving the health and outcomes of veterans with COVID-19, we have assembled a team of internationally recognized scientists with expertise in coronavirus virology and in lung biology coupled with a strong foundation of our own prior work on surfactant biology, lung injury, and fibrotic repair funded, in part, by the VA Merit Review program. Utilizing this expertise, this proposal is directed at filling in large knowledge gaps that exist in the pathogenesis of nCoV induced respiratory failure. The motivation for this investigation has been fueled by the recent recognition that the alveolar type 2 (AT2) epithelial cell of the distal lung has emerged as an important portal of entry for SCoV- 2. The central hypothesis of this application is that AT2 cells infected with nCoV acquire defects in surfactant biosynthesis/metabolism, activate cellular stress pathways, and develop alterations in progenitor cell function all of which promote hypoxic respiratory failure, persistent lung inflammation and injury, and impact recovery through effects on epithelial repair capacity. To test this, we will leverage an established murine model of CoV infection (MHV-1) with a pulmonary phenotype combined with reductionist studies supported by ex vivo infection of primary human AT2 cells obtained from a robust human lung pipeline with an already in hand SARS-CoV-2 isolate. Our experimental approach will interrogate these preclinical models using tools and reagents available in our program, to map the effect of CoV infection on distal lung cell populations with a focus on identifying and translating molecular mechanisms linking the disrupted AT2 function with altered surfactant biology and proinflammatory/profibrotic cell cross talk in the alveoilar niche. In Specific Aim 1, we will first define temporal changes in distal lung epithelial endophenotypes focusing on the ontogeny of the disruption of AT2 homeostasis by viral infection using a well characterized mouse model of MHV-1 lung infection. Using both unbiased approaches such as transcriptomic profiling as well as classical cell biology and biochemistry this aim will investigate CoV induced changes in surfactant metabolism/biophysical activity, AT2 cell stress (i.e. ER stress, proteasome dysfunction, autophagy malfunction, changes in mitochondrial dynamics/ / bioenergetics) and AT2 progenitor cell function. In Specific Aim 2, armed with this “functional map” of the mouse CoV-lung and aberrant AT2 behaviors, we will translate the identified lead targets and mechanisms to human AT2 cells utilizing both primary AT2 cultures as well as precision cut lung slices (PCLS) infected with SARS-CoV-2. The research design involves the analysis of virus-dependent AT2 surfactant protein and lipid metabolism, interrogation of AT2 cell quality control pathways, and functional evaluation of AT2 progenitor function phenotypes in the SCoV-2 infected human epithelial cells. By understanding the path to epithelial injury / dysfunction from nCoV, the mechanisms and affected lung cell populations identified using these models will improve the understanding of sCOV2/COVID- 19 syndrome, promote identification of new target pathways, and can be cross-purposed to test emerging therapies for both the current and future nCoV pandemics.

抽象的 严重急性呼吸系统综合症 (SARS) 相关冠状病毒 2 (SCoV2) 是导致 COVID-19 的原因 以难治性急性肺损伤为特征的综合征，导致严重缺氧性呼吸衰竭 尽管新型冠状病毒反复造成健康和经济破坏。 （nCoV）在过去 20 年中，包括 SCoV2 及其前身 SCoV1 和 MERS-CoV， 对于更清楚地了解病毒与宿主细胞的相互作用以及 确定新的治疗靶点来解决这些问题，最终目标是改善健康。 和患有 COVID-19 的退伍军人的结果，我们组建了一个由国际公认的科学家组成的团队 拥有冠状病毒病毒学和肺部生物学方面的专业知识以及我们自己之前工作的坚实基础 关于表面活性剂生物学、肺损伤和纤维化修复的研究部分由 VA 优异评审计划资助。 这项专业知识旨在填补新型冠状病毒发病机制中存在的巨大知识空白 最近的认识推动了这项研究的动机。 远端肺的 2 型肺泡 (AT2) 上皮细胞已成为 SCoV 的重要进入门户 2.本申请的中心假设是感染nCoV的AT2细胞获得表面活性剂缺陷 生物合成/代谢，激活细胞应激途径，并改变祖细胞功能 其中促进缺氧性呼吸衰竭、持续性肺部炎症和损伤，并影响恢复 为了测试这一点，我们将利用已建立的 CoV 小鼠模型。 具有肺部表型的感染（MHV-1）结合离体感染支持的还原论研究 从强大的人肺管道中获得的原代人 AT2 细胞，其中含有 SARS-CoV-2 我们的实验方法将使用可用的工具和试剂来询问这些临床前模型。 在我们的项目中，绘制冠状病毒感染对远端肺细胞群的影响，重点是识别和 翻译将被破坏的 AT2 功能与表面活性剂生物学联系起来的分子机制 在特定目标 1 中，我们将首先定义时间。 远端肺上皮内表型的变化集中于 AT2 稳态破坏的个体发育 通过病毒感染，使用特征明确的 MHV-1 肺部感染小鼠模型。 这一目标将采用转录组分析以及经典细胞生物学和生物化学等方法 研究 CoV 诱导的表面活性剂代谢/生物物理活性、AT2 细胞应激（即 ER 应激、 蛋白酶体功能障碍、自噬功能障碍、线粒体动力学//生物能学的变化）和 AT2 在特定目标 2 中，配备了小鼠 CoV 肺和异常的“功能图”。 AT2 行为，我们将利用这两种方法将已确定的先导目标和机制转化为人类 AT2 细胞 原代 AT2 培养物以及感染 SARS-CoV-2 的精密切割肺切片 (PCLS)。 涉及病毒依赖性 AT2 表面活性蛋白和脂质代谢的分析、AT2 细胞的询问 SCoV-2 感染者 AT2 祖细胞功能表型的质量控制途径和功能评估 通过了解新型冠状病毒导致上皮细胞损伤/功能障碍的途径和机制。 使用这些模型确定的受影响的肺细胞群将提高对 sCOV2/COVID-的理解 19 综合征，促进新目标途径的识别，并且可以交叉目的测试新兴的 针对当前和未来的新型冠状病毒大流行的治疗方法。