Mechanisms and Treatment of SARS-CoV-2 induced Lung Endothelial Injury

项目摘要/摘要 冠状病毒病2019年(新冠肺炎)是由冠状病毒引起的一种毁灭性的全身性炎症综合征 SARS-CoV-2在过去的一年里在美国造成了50多万人死亡，死亡率如此之高 在很大程度上归因于急性肺损伤(ALI)或急性呼吸窘迫综合征的发展 (ARDS)。SARS-CoV-2进入细胞需要SARS-CoV-2尖峰蛋白(S)与主要蛋白的直接结合 宿主蛋白酶TMPRSS2和血管紧张素转换酶2(ACE-2)受体在 多种宿主细胞类型。预防SARS-CoV-2传播的有效疫苗的开发代表着 这将有助于遏制新冠肺炎大流行，但出现了令人担忧的变种 如B1.1.7、P1和B1.351，可逃避疫苗诱导的体液中和反应 免疫反应突出表明迫切需要开发新的疗法来补充疫苗接种工作。 基于我们具有挑衅性的支持数据，我们提出了SARS-CoV-2病毒的总体假设 诱导性肺内皮损伤是新冠肺炎诱导的适应性不良炎症损伤的必备因素，可 在治疗上有针对性。我们提出以下具体目标：在目标1中，我们将定义本质和潜在的 新冠肺炎致ALI/ARDS肺内皮细胞损伤机制的研究我们将检验这一假设 肺内皮细胞损伤程度是决定多发性SARS病原性和死亡率的关键因素。 冠状病毒2型变种。我们将建立SARS-CoV-2诱导的肺血管损伤和代偿性肺内皮细胞 使用两个互补的人源化ACE2小鼠模型进行再生，EC特异性遗传谱系追踪， VE-钙粘蛋白的遗传稳定性和单细胞RNA测序。在目标2中，我们将定义有效性和最优 预防和化解SARS冠状病毒的两种靶向药物治疗策略的时间窗 2诱导肺内皮细胞损伤。我们将检验这样一种假设，即一种经工程改造的可溶性HACE-2肽具有 与野生型HACE-2多肽相比，在减轻肺内皮细胞损伤方面的疗效更高，而且远期疗效更好 欧共体重新编程，防止病毒进入和传播多种SARS-CoV-2变种。我们将测试 推论和使用改良的IL-1受体拮抗剂靶向抑制IL-1β信号转导是 对多重SARS-CoV2诱导的前馈炎症环和内皮损伤的保护作用 变种。我们将使用两种HACE-2小鼠模型，并比较不同的给药途径(气管内和气管内 静脉注射)，并识别用于治疗干预的最佳时间窗口。

PROJECT SUMMARY / ABSTRACT Coronavirus disease 2019 (COVID-19) is a devastating systemic inflammatory syndrome caused by the coronavirus SARS-CoV-2 which has resulted in over 500,000 deaths in the US during the past year, with this high rate of mortality being attributed in large part to the development of Acute Lung Injury (ALI) or Acute Respiratory Distress Syndrome (ARDS). SARS-CoV-2 entry into cells requires the direct binding of the SARS-CoV-2 spike (S)-protein to the principal host protease-TMPRSS2 and the angiotensin converting enzyme 2 (ACE-2) receptors which are expressed in multiple host cell types. The development of efficacious vaccines to prevent the spread of SARS-CoV-2 represents a tremendous advance that will help curb the COVID-19 pandemic, however the emergence of variants of concern such as the B1.1.7, P1 and B1.351 which can evade the neutralizing responses of the vaccine-induced humoral immune response underscores the urgent need to develop novel therapeutics to complement the vaccination efforts. Based on our provocative Supporting Data, we have formulated the overarching hypothesis that SARS-CoV-2 induced lung endothelial injury is a requisite element of COVID-19 induced maladaptive inflammatory injury that can be therapeutically targeted. We propose the following specific aims: In Aim 1, we will define the nature and underlying mechanisms of lung endothelial injury underlying COVID-19-induced ALI/ARDS. We will test the hypothesis that the degree of lung endothelial injury is a key determinant of the overall pathogenicity and mortality of multiple SARS- CoV-2 variants. We will establish SARS-CoV-2-induced lung vascular injury and compensatory lung endothelial regeneration using two complementary humanized ACE2 mouse models, EC-specific genetic lineage tracing, genetic stabilization of VE-cadherin and single cell RNA-Sequencing. In Aim 2, we will define the efficacy and optimal temporal windows for two targeted pharmacological therapeutic strategies in preventing and resolving SARS-CoV- 2 induced lung endothelial injury. We will test the hypothesis that an engineered soluble hACE-2 peptide has a higher therapeutic efficacy than the wildtype hACE-2 peptide in reducing lung endothelial injury as well as long-term EC reprogramming by preventing viral entry and dissemination of multiple SARS-CoV-2 variants. We will test the corollary hypothesis and that targeted inhibition of IL1β-signaling using a modified IL-1 Receptor antagonist is protective against the feed-forward inflammatory loop and endothelial injury induced by multiple SARS-CoV2 variants. We will use two hACE-2 mouse models as well as compare distinct routes of delivery (intratracheal versus intravenous) and identify the optimal temporal windows for the therapeutic intervention.