A novel model to study COVID-19 and Hypertension

7.项目摘要/摘要 动物模型对于理解新冠肺炎的发病机制和发展都是不可或缺的 疫苗。它们对于识别特定高危人群中新冠肺炎的病因也很重要，例如 既往有高血压的个体。虽然有仓鼠、雪貂、猫、非人灵长类动物和K18- HACE2转基因小鼠作为研究新冠肺炎的可能模型，均不能达到研究HACE2基因的目的 高血压与新冠肺炎易感性之间的关系，因为(1)野生型研究模型不存在 感染人类SARS-CoV-2和/或(2)他们遗传上不容易患高血压。为了填满这个 针对尚未得到满足的需求，我们建议开发研究新冠肺炎的体内实验平台。 高血压。在初步数据中，我们提出了一种新的敲入鼠模型发展的证据。 用CRISPR/CAS9技术编辑的高血压大鼠(S)表达人血管紧张素转换酶2 基因(HACE2)，是SARS-CoV-2的受体。HACE2基因被插入以取代大鼠的ACE2基因。 还产生了作为对照菌株的所需的大鼠ACE2基因敲除(rAce2-KO)。通过比较这些 2个菌株，在目的1中，我们将检验该大鼠模型是否适合研究新冠肺炎。此外，基于我们的 最近发表的使用无菌大鼠的研究表明，将微生物区系引入无菌大鼠 上调结肠血管紧张素转换酶2表达和血压的现有知识结合较强 盐敏感型高血压与肠道微生物区系的关系；在目标2中，我们将检验假设 在高血压状态下，宿主和肠道微生物群之间失去正常共生是导致高血压的原因 ACE2在多个器官中的表达水平较低。

7. Project Summary/Abstract Animal models fare indispensable for understanding the pathology of COVID-19 as well as for developing vaccines. They are also important to discern the etiology of COVID-19 in specific groups at risk, such as individuals with pre-existing hypertension. While there are hamsters, ferrets, cats, nonhuman primates and K18- hACE2 transgenic mice as possible models for studying COVID-19, none serves the purpose of studying the relationship between hypertension and susceptibility to COVID-19 because (1) wild-type research models do not get infected with the human SARS-CoV-2 and/or (2) they are not genetically prone to hypertension. To fill this unmet need, we propose to develop in vivo experimental platform for studying COVID-19 in the setting of hypertension. In preliminary data, we present evidence for the development of a novel knock-in rat model of the hypertensive Dahl Salt-sensitive (S) rat edited using the CRISPR/Cas9 technology to express the human ACE2 gene (hACE2), which is the receptor for SARS-CoV-2. The gene hACE2 is inserted to replace the rat Ace2 locus. The required rat Ace2 knockout as the control strain (rAce2-KO) has also been generated. By comparing these 2 strains, in Aim 1 we will examine the suitability of this rat model for studying COVID-19. Further, based on our recent published work using germ-free rats indicating that introduction of microbiota to germ-free rats upregulated colonic Ace2 expression and blood pressure combined with the existing knowledge of a strong relationship between salt-sensitive hypertension and the gut microbiota; in Aim 2, we will test the hypothesis that the loss of normal symbiosis between the host and gut microbiota during a hypertensive state is responsible for the lower ACE2 expression in multiple organs.