A novel model to study COVID-19 and Hypertension

7. 项目总结/摘要 动物模型对于理解 COVID-19 的病理学以及开发不可或缺的 疫苗。它们对于识别特定高危人群中的 COVID-19 病因也很重要，例如 患有高血压的人。虽然有仓鼠、雪貂、猫、非人类灵长类动物和 K18- hACE2 转基因小鼠作为研究 COVID-19 的可能模型，但没有一个能够用于研究 高血压与 COVID-19 易感性之间的关系，因为 (1) 野生型研究模型不 感染人类 SARS-CoV-2 和/或 (2) 他们在遗传上没有患高血压的倾向。为了填补这个 未满足的需求，我们建议开发体内实验平台来研究COVID-19 高血压。在初步数据中，我们提供了开发新型基因敲入大鼠模型的证据 使用 CRISPR/Cas9 技术编辑高血压 Dahl 盐敏感 (S) 大鼠以表达人类 ACE2 基因（hACE2），它是 SARS-CoV-2 的受体。插入基因 hACE2 以取代大鼠 Ace2 基因座。 所需的大鼠 Ace2 敲除作为对照菌株 (rAce2-KO) 也已生成。通过比较这些 2 株，在目标 1 中，我们将检查该大鼠模型用于研究 COVID-19 的适用性。此外，根据我们的 最近发表的使用无菌大鼠的研究表明将微生物群引入无菌大鼠 结肠 Ace2 表达和血压的上调与现有知识相结合 盐敏感性高血压与肠道菌群的关系；在目标 2 中，我们将检验以下假设： 高血压状态下宿主和肠道微生物群之间正常共生的丧失是导致 多个器官中 ACE2 表达较低。

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.