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 严重的急性呼吸综合征（SARS）相关冠状病毒2（SCOV2）是Covid-19的原因 综合征以难治性急性肺损伤为特征，导致剧烈的低氧呼吸衰竭 和高死亡率。尽管新型冠状病毒造成了循环健康和经济破坏 （NCOV）在过去的20年中，包括SCOV2及其前任SCOV1和MERS-COV 仍然需要更清楚地了解病毒宿主相互作用以及 识别新的治疗靶标。解决这些问题的最终目标是改善健康 以及在Covid-19的退伍军人的成果，我们组建了一个国际认可的科学家团队 具有冠状病毒病毒学和肺部生物学方面的专业知识，加上我们自己先前工作的强大基础 关于表面活性剂生物学，肺损伤和纤维化修复，部分由VA功绩审查计划资助。利用 这种专业知识，该提案是针对NCOV发病机理中存在的较大知识差距 诱发呼吸衰竭。最近认识到，这项调查的动机被搞砸了 肺肺的肺泡2（AT2）上皮细胞已成为SCOV-的重要入口门户 2。该应用的中心假设是感染了NCOV的AT2细胞在表面活性剂中获得缺陷 生物合成/代谢，激活细胞应激途径并发展祖细胞功能的改变所有 其中促进缺氧性呼吸衰竭，持续性肺部感染和损伤以及影响恢复 通过对上皮维修能力的影响。为了测试这一点，我们将利用COV的既定鼠模型 感染（MHV-1）具有肺表型，并结合了体内感染支持的还原病研究 从稳健的人类肺管道获得的原代人AT2细胞，并已经掌握了SARS-COV-2 隔离。我们的实验方法将使用可用的工具和试剂询问这些临床前模型 在我们的计划中，绘制COV感染对远端肺细胞群体的影响，重点是识别和 翻译分子机制，将破坏AT2功能与表面活性剂生物学改变和 肺泡利基中的促炎/纤维化细胞交叉讲座。在特定目标1中，我们将首先定义临时性 远端肺上皮内表型的变化，重点是AT2稳态破坏的本体发育 通过病毒感染，使用良好的MHV-1肺部感染的小鼠模型。使用两个公正 诸如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/生物物理活性的变化，AT2细胞应激（即ER应激， 蛋白酶体功能障碍，自噬故障，线粒体动力学 / /生物能力的变化）和AT2 祖细胞功能。在特定的目标2中，用小鼠cov-ung和异常的“功能图”武装 AT2行为，我们将使用两者都将确定的铅靶和机制转化为人AT2细胞 原发性AT2培养物以及被SARS-COV-2感染的精确切割肺切片（PCL）。研究设计 涉及病毒依赖性AT2表面活性剂蛋白和脂质代谢的分析，AT2细胞的询问 质量控制途径和AT2祖细胞功能表型的功能评估感染了 人上皮细胞。通过了解NCOV的上皮损伤 /功能障碍的路径，机制 使用这些模型鉴定的受影响的肺细胞群体将改善对SCOV2/covid-的理解 19综合征，促进新目标途径的识别，可以交叉插入以测试出现 当前和未来的NCOV大流行病的疗法。