Human organoid model for COVID-19 myocarditis

项目摘要：急性心脏损伤（ACI）发生在高达20-25%的住院COVID-19患者中， 与发病率和死亡率风险增加有关。COVID-19已被证明可诱导免疫 系统“过度放电”和“不放电”，导致超生理炎症。这种细胞因子风暴已经被 显示通过直接细胞因子损伤和间接机制（例如，招聘 促炎免疫细胞进入器官）。心肌炎（例如，单核细胞浸润）是常见的并发症 在COVID-19 ACI心脏中。然而，浸润的单核细胞对COVID-19 ACI心脏的影响仍然存在 定义不清由于先前的研究仅限于临床样本（例如，外周血， 尸检/活检组织）或体外2D共培养实验，这些研究产生有限的功能性见解。3D 器官型模型提供了一个强大的平台来研究心脏和心脏之间的功能相互作用， 免疫细胞循环。为了开发用于疾病建模的人类心脏器官型模型，我们 开发了由人类多能干细胞衍生的心肌细胞组成的3D人类心脏类器官 在一些实施方案中，所述细胞包括人PSC-CM、人心脏成纤维细胞、内皮细胞和基质细胞。我们的初步数据显示， 白细胞介素（IL）-1b处理的类器官概括了转录组，结构和功能的关键特征， COVID-19 ACI心脏。由于IL-1b不是COVID-19特异性刺激物，因此这些结果为使用 来自COVID-19 ACI患者的血清，以概括COVID-19细胞因子对心脏的损伤。此外该 排除类器官中的免疫细胞限制了COVID-19中过度炎症的全面重演 ACI心脏。该提案的目标是利用血清和外周血单核细胞（PMBCs） 从COVID-19 ACI患者中收获，以1）模拟COVID-19细胞因子损伤对人类心脏的影响， 2)开发第一个体外COVID-19心肌炎类器官模型，以模拟免疫细胞浸润， COVID-19 ACI心脏并评估浸润的COVID-19单核细胞。这项提议的核心假设是 是浸润的COVID-19免疫细胞（例如，单核细胞）加剧COVID-19 ACI的过度炎症 心中这项建议是创新的，因为它将首次开发心肌炎的器官型模型 模拟免疫细胞渗入心肌因此，我们将追求以下两个目标：1） 确定COVID-19 ACI血清对人类心脏类器官的影响，以及2）确定 COVID-19 ACI血清处理类器官以从COVID-19 ACI患者招募免疫细胞。拟议 研究将导致后续的R 01应用，重点是渗透的影响和机制， COVID-19 ACI心脏中的单核细胞。此外，心肌炎的3D器官型模型可用于 免疫调节药物对心脏作用的机制研究。

Project Summary: Acute Cardiac Injuries (ACIs) occur in up to 20-25% of hospitalized COVID-19 patients and are associated with increased risks of morbidity and mortality. COVID-19 has been shown to induce immune system “overfiring” and “misfiring”, resulting in supraphysiological inflammation. Such cytokine storms have been shown to lead to organ damage through both direct cytokine insults and indirect mechanisms (e.g., recruitment of proinflammatory immune cells into organs). Myocarditis (e.g., monocyte infiltration) is a common complication in COVID-19 ACI hearts. However, the impacts of the infiltrated monocytes on COVID-19 ACI hearts remain under-defined. As previous studies have been limited to either clinical samples (e.g., peripheral blood, autopsy/biopsy tissues) or in vitro 2D co-culture experiments, these studies yield limited functional insights. 3D organotypic models provide a powerful platform to study the functional interactions between hearts and immune cells in circulation. To develop an organotypic model of human hearts for disease modeling, we developed 3D human cardiac organoids composed of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs), human cardiac fibroblasts, endothelial cells, and stromal cells. Our preliminary data showed the Interleukin (IL)-1b treated organoids recapitulated key features of transcriptome, structure, and function of COVID-19 ACI hearts. As IL-1b is not a COVID-19 specific stimulus, these results laid the foundation to use serum from COVID-19 ACI patients to recapitulate the COVID-19 cytokine insults to the hearts. In addition, the exclusion of immune cells in the organoids has limited the full recapitulation of hyperinflammation in COVID-19 ACI hearts. The goal of this proposal is to leverage the serum and peripheral blood mononuclear cells (PMBCs) harvested from COVID-19 ACI patients to 1) simulate the effects of COVID-19 cytokine insults on human hearts, 2) develop the first in vitro COVID-19 myocarditis organoid model to simulate immune cell infiltration to COVID-19 ACI hearts and assess the infiltrated COVID-19 monocytes. The central hypothesis of this proposal is that infiltrated COVID-19 immune cells (e.g., monocytes) exacerbate the hyperinflammation of COVID-19 ACI hearts. This proposal is innovative in that it will, for the first time, develop an organotypic model of myocarditis to simulate immune cell infiltration into myocardium. Accordingly, we will pursue the following 2 Aims: 1) Determine the effects of COVID-19 ACI serum on human cardiac organoids, and 2) Determine the ability of COVID-19 ACI serum treated organoids to recruit immune cells from COVID-19 ACI patients. The proposed studies will lead to follow-up R01 applications focusing on the effects and mechanisms of the infiltrated monocytes in COVID-19 ACI hearts. In addition, the 3D organotypic model of myocarditis can be used for mechanistic studies of the effects of immunomodulatory drugs on hearts.