Mechanistic characterization of SARS-CoV2 associated kidney injury

SARS-CoV2 是一种高度传染性的新型人类冠状病毒，可导致 2019 年冠状病毒病 (COVID-19) 19）。目前美国已有超过 1650 万人确诊感染 SARS-CoV2，超过 30 万人确诊感染 已经死了。严重的 COVID-19 的特点是肺部和全身炎症以及多器官 功能障碍，相当一部分重症新冠肺炎患者出现急性肾损伤。机制 SARS-CoV2 是如何引发如此严重的发病机制的，人们知之甚少。最近的临床研究已 表明细胞死亡，尤其是坏死性凋亡的诱导，可能是严重 COVID-19 的预测因素 疾病。宿主限制坏死性凋亡的机制尚不清楚。在初步数据中我们已经显示 干扰素诱导蛋白 ISG15 充当坏死性凋亡及其下游的负调节因子 病毒感染期间的炎症反应。我们还表明，ISG15 缺陷小鼠会迅速死亡 以大量释放促炎细胞因子为特征的肾脏缺血再灌注损伤。 在本提案中，我们将测试 ISG15 作为调节中关键宿主限制因素的假设 肾脏内的程序性坏死性凋亡和下游炎症反应，以限制急性肾损伤 SARS-CoV2 感染期间。我们将利用源自诱导多能干细胞的肾脏类器官，其中 ISG15 已被 CRISPR 删除，这是一种与肾类器官和原代气管上皮共培养系统 培养物（hTEC）和 SARS-CoV-2 体内小鼠模型，提出几个问题，包括：1）SARS- 冠状病毒2通过直接病毒转导或响应全身性损伤诱导肾上皮细胞损伤 炎症？ 2) ISG15是否调节坏死性细胞死亡以及促炎细胞因子/趋化因子 SARS-CoV2 感染期间肾上皮细胞的产生？ 3) 坏死性凋亡及其调控是否通过 ISG15 会导致 SARS-CoV2 感染期间的急性肾损伤吗？总的来说，我们的研究将提供重要的 深入了解限制坏死性凋亡的宿主因素，并可能是导致严重 COVID-19 的重要因素 诱发肾损伤。

SARS-CoV2 is a highly contagious, novel human coronavirus that causes coronavirus disease 2019 (COVID- 19). Currently over 16.5 million people in the US have confirmed infection with SARS-CoV2 and over 300,000 have died. Severe COVID-19 is characterized by pulmonary and systemic inflammation and multi-organ dysfunction, with a significant portion of severe COVID patients developing acute kidney injury. The mechanism by which SARS-CoV2 triggers such severe pathogenesis is poorly understood. Recent clinical studies have suggested that cell death, especially the induction of necroptosis, may be a predictor of severe COVID-19 disease. The mechanism by which the host restricts necroptosis is unclear. In preliminary data we have shown that the interferon induced protein, ISG15, acts as a negative regulator of necroptosis and its downstream inflammatory responses during viral infection. We have also shown that ISG15 deficient mice rapidly succumb to ischemia-reperfusion injury of the kidney characterized by a massive release of proinflammatory cytokines. In this proposal we will test the hypothesis that ISG15 serves as a critical host restriction factor in regulating programmed necroptosis and downstream inflammatory responses within the kidney to limit acute kidney injury during SARS-CoV2 infection. We will utilize kidney organoids derived from induce pluripotent stem cells in which ISG15 has been deleted by CRISPR, a co-culture system with kidney organoids and primary tracheal epithelial cultures (hTECs), and in vivo mouse model of SARS-CoV-2 to ask several questions including: 1) Does SARS- CoV2 induce damage to kidney epithelial cells via direct viral transduction or in response to systemic inflammation?; 2) Does ISG15 modulate necroptotic cell death as well as proinflammatory cytokine/chemokine production in kidney epithelial cells during SARS-CoV2 infection?; 3) Does necroptosis and its regulation by ISG15 contribute to acute kidney injury during SARS-CoV2 infection? Overall, our studies will provide important insight into host factors that restrict necroptosis and could be an important contributor to severe COVID-19 induced kidney injury.