Administrative Supplement to R21: Mechanism and in vivo activity of novel glycan-based therapy against flavivirus endothelial permeability and vascular leak

R21的补充剂：基于多糖的抗黄病毒新疗法的机制和体内活性 内皮通透性与血管渗漏 针对SARS-CoV-2感染的治疗药物评价及致病机制探讨 SARS-CoV-2引发的肺功能障碍 摘要 新出现的严重急性呼吸综合征-冠状病毒2(SARS-CoV-2)，是引起 冠状病毒病2019年(新冠肺炎)正在世界各地迅速传播，已影响199个国家， 预计将感染高达60%的人口，迄今病死率约为4.4%。新疗法 目前我们正在研究环糊精的抗黄病毒特性 化合物(CD)，具有广泛的抗病毒活性，我们建议在这里扩大这项研究，以测试这些 化合物在人支气管上皮细胞中的抗SARS-CoV-2活性(目标1)。首先，我们将快速跟踪 FDA批准的CD在我们的收藏中，然后筛选其余的。OSC Ralph Baric博士(北卡罗来纳大学)将确认我们最 在原代人类细胞中有希望的候选人，并合作建立进一步的研究，在他的 老鼠模型。根据以前的文献和通过父母资助获得的数据，我们假设 这些化合物可能通过灭活病毒粒子和潜在地抑制细胞而具有直接的杀毒活性。 通过阻断SARS-CoV-2刺突糖蛋白(S)与多糖和/或病毒的相互作用而附着 细胞表面的受体血管紧张素转换酶2(ACE2)。尽管受感染的患者会屈从于 涉及血管渗漏的急性呼吸窘迫综合征(ARDS)，这种病理的病毒触发因素是 不清楚。对SARS-CoV-1的实验发现，ACE2与病毒颗粒一起内化在 感染降低了细胞表面的ACE2水平，导致血管紧张素II活性增加。血管紧张素 II活性被认为会导致血管活性分子如血管内皮生长因子的上调 F(血管内皮生长因子)和细胞间连接的破坏，都会导致血管渗漏。在目标2中，我们优化的系统 用于研究内皮细胞功能障碍，这是多年来研究黄病毒的结果，包含在 家长资助将用于研究病毒S蛋白诱导的SARS-CoV-2血管病理 和次级介质如血管内皮生长因子。正如我们已经在体外观察到的防泄漏和抗病毒特性 对于一些经过测试的CD，我们还建议测试这些候选CD作为治疗新冠肺炎疾病的药物 表现形式。因此，这项补充拨款建议有可能界定引发SARS-CoV-2 S的因素- 介导的血管泄漏，导致ARDS，以及测试CD作为针对病毒感染的治疗药物 直接或间接通过下游发病机制。FDA批准的CD和衍生品 由于新冠肺炎疗法有可能被迅速开发出来用于患者，因此是有效的。 1

Supplement to R21: Mechanism and in vivo activity of novel glycan-based therapy against flavivirus endothelial permeability and vascular leak Evaluation of therapeutics targeting SARS-CoV-2 infection and defining pathogenic mechanisms of SARS-CoV-2-triggered pulmonary dysfunction Abstract The emerging severe acute respiratory syndrome-corona virus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), is spreading rapidly across the world, already affecting 199 countries, and predicted to infect up to 60% of the population, with a ~4.4% case fatality rate to date. Novel therapeutics are desperately needed, and as we are currently investigating anti-flavivirus properties of cyclodextrin compounds (CDs), which have broad antiviral activity, we propose here to expand this investigation to test these compounds for anti-SARS-CoV-2 activity in human bronchial epithelial cells (Aim 1). First, we will fast-track the FDA-approved CDs in our collection, and then screen the rest. OSC Dr. Ralph Baric (UNC) will confirm our most promising candidates in primary human cells and collaborate on setting up further studies to test them in his mouse models. Based on previous literature and data acquired through the parent grant, we hypothesize that these compounds may have direct virucidal activity by inactivating virions, as well as potentially inhibiting cell attachment by blocking the SARS-CoV-2 spike glycoprotein (S) from interacting with glycans and/or the viral receptor angiotensin converting enzyme 2 (ACE2) on the cell surface. Though infected patients succumb to acute respiratory distress syndrome (ARDS) involving vascular leak, the viral triggers of this pathology are unclear. Experiments with SARS-CoV-1 found that internalization of ACE2 along with virus particles upon infection reduces ACE2 levels on the cell surface, resulting in increased angiotensin II activity. The angiotensin II activity is believed to result in upregulation of vasoactive molecules such as vascular endothelial growth factor F (VEGF) and disruption of intercellular junctions, both inducing vascular leak. In Aim 2, our optimized system for the study of endothelial cell dysfunction, resulting from many years of work with flaviviruses and included in the parent grant, will be applied to investigate SARS-CoV-2 vascular pathology induced by the viral S protein and secondary mediators like VEGF. As we have already observed in vitro anti-leak as well as antiviral properties for some of the tested CDs, we also propose to test these candidates as therapeutics to treat COVID-19 disease manifestations. As such, this supplemental grant proposal has the potential to define triggers of SARS-CoV-2 S- mediated vascular leak, contributing to ARDS, as well as testing CDs as therapeutics targeting viral infection directly and indirectly via downstream pathogenesis. FDA-approved CDs and derivatives that prove to be effective as COVID-19 treatments have the potential to be rapidly developed for potential use in patients. 1