EAGER: Coronavirus infection of human lung epithelium and leukocytes: mechanisms and treatment

EAGER：冠状病毒感染人肺上皮和白细胞：机制和治疗

• 批准号: 2032273
• 负责人: Rabindra Tirouvanziam
• 金额: $ 20万
• 依托单位: Emory University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2021-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2032273&HistoricalAwards=false
• 关键词: EAGER; Coronavirus; infection; human; lung

COVID-19, classified as a viral pandemic on 3/11/2020, has rapidly spread globally and caused over 250,000 deaths worldwide by 5/5/2020. COVID-19 symptoms range from mild fever and sore throat, to acute respiratory distress syndrome (ARDS) and death. SARS-CoV-2, the virus that causes COVID-19, avoids detection by the body’s immune system and enters the epithelial cells lining the airways, where it replicates and recruits a flood of immune cells, leading to what is called a “cytokine storm.” This “storm” can inflame the tissues surrounding the infection and eventually shut down breathing entirely. To date, basic studies on virus entry, propagation, and drug testing use non-human, non-lung models, like the Vero African green monkey kidney cell line, which severely limits efforts to understand COVID-19 disease and develop therapies. To address this problem, the objective of this project is to develop a platform emulating the human lung environment to study how SARS-CoV-2 interacts with the lung epithelial cells and with immune cells recruited to the lung and how therapies may modulate these interactions to benefit patients. The approach makes use of a model that the investigators have validated for studies of Cystic Fibrosis and Acute Respiratory Distress Syndrome (ARDS). The model features cultures of human airway epithelium grown on scaffolds that enable virus exposure, immune cell attraction and administration of existing drugs being considered for COVID-19 treatment. The platform developed will open broad opportunities for research not only on SARS-CoV-2, but also on other conditions (e.g., respiratory viruses or environmental exposures) that impact human lung physiology and health.The objective of this project is to engineer and validate a novel technological platform emulating the human lung environment to study how SARS-CoV-2, the causative agent of COVID-19 disease, interacts with epithelial cells lining the lung and with leukocytes recruited to the lung in response to infection, and how therapies may modulate these interactions to benefit patients. Unique features of the life-like platform include: (1) the use of human airway cells (both alveolar and bronchial epithelium) at ALI (Air-Liquid Interface) to propagate the virus over several days which enables the system to acquire the receptors and pathways relevant to human lung infections; (2) the use of human blood leukocytes transmigrated at chosen timepoints during infection, which is a key advantage over in vitro setups that use blood in lieu of lung leukocytes or animal models; and (3) due to the inclusion of all key components in the disease (virus, epithelium, leukocytes), the ability to assess drugs for their effects on the whole system, regardless of their primary target. The underlying hypothesis of the project is that SARS-CoV-2 causes pathology upon infection of the human lung by delaying interferon signaling, allowing the virus to infect monocytes, after which a breakdown in innate control occurs resulting in a cytokine storm, and in turn, overwhelming neutrophil recruitment and ARDS (Acute Respiratory Distress Syndrome). The research is organized under two Aims: (1) Determine the ability of the SARS-CoV-2 virus to enter and replicate in human lung epithelial cells and lung-recruited leukocytes and (2) Identify key pathways in human lung epithelial cells and lung-recruited leukocytes that can be modulated by existing drugs to prevent disease, e.g., remdesivir, baricitinib, anti-lL-6, anakinra, as well as a combination of remdesivir and baricitinibs which should impact both the virus and the inflammation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

2019冠状病毒病于2020年11月3日归类为病毒性大流行病，于全球迅速蔓延，截至2020年5月5日，已导致全球逾250，000人死亡。 COVID-19的症状从轻微发烧和喉咙痛到急性呼吸窘迫综合征（ARDS）和死亡。 引起COVID-19的SARS-CoV-2病毒避开了人体免疫系统的检测，进入了气道上皮细胞，在那里复制并招募大量免疫细胞，导致所谓的“细胞因子风暴”。这种“风暴”会使感染周围的组织发炎，最终完全停止呼吸。 到目前为止，关于病毒进入、繁殖和药物测试的基础研究使用的是非人类、非肺模型，如非洲绿绿色猴肾细胞系，这严重限制了对COVID-19疾病的理解和开发治疗方法的努力。 为了解决这一问题，该项目的目标是开发一个模拟人类肺部环境的平台，以研究SARS-CoV-2如何与肺上皮细胞和招募到肺部的免疫细胞相互作用，以及治疗如何调节这些相互作用以使患者受益。 该方法利用了研究人员已经验证用于囊性纤维化和急性呼吸窘迫综合征（ARDS）研究的模型。该模型的特点是在支架上生长的人类气道上皮细胞培养物，这些细胞能够暴露病毒，吸引免疫细胞，并给予正在考虑用于COVID-19治疗的现有药物。开发的平台将为研究SARS-CoV-2和其他疾病（例如，呼吸道病毒或环境暴露）影响人类肺部生理和健康。该项目的目标是设计和验证一种模拟人类肺部环境的新型技术平台，以研究COVID-19疾病的病原体SARS-CoV-2如何与肺部上皮细胞以及感染后招募到肺部的白细胞相互作用，以及治疗如何调节这些相互作用以使患者受益。仿真平台的独特之处包括：（1）使用人体气道细胞（肺泡和支气管上皮）（空气-液体界面）以在数天内传播病毒，这使得系统能够获得与人类肺部感染相关的受体和途径;（2）使用在感染期间选定时间点迁移的人血白细胞，这是优于使用血液代替肺白细胞或动物模型的体外设置的关键优势;以及（3）由于疾病的所有关键成分都包括在内（病毒、上皮细胞、白细胞），评估药物对整个系统的作用的能力，而不管其主要靶点。该项目的基本假设是，SARS-CoV-2通过延迟干扰素信号传导，使病毒感染单核细胞，在此之后发生先天控制的崩溃，导致细胞因子风暴，进而导致压倒性的中性粒细胞募集和ARDS（急性呼吸窘迫综合征），从而在感染人肺后引起病理学。这项研究有两个目的：（1）确定SARS-CoV-2病毒进入人肺上皮细胞和肺募集白细胞并在其中复制的能力;（2）确定人肺上皮细胞和肺募集白细胞中的关键通路，这些通路可以通过现有药物进行调节以预防疾病，例如，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。