Mechanobiology of aortic smooth muscle cells in human iPSC-based models of Marfan Syndrome

项目总结 马凡综合征(MFS)是最常见的遗传性结缔组织疾病之一，每5000人中就有1人患病 并在多个器官系统中具有破坏性表现，特别是心血管系统。 MFS是一种常染色体显性遗传病，由纤维蛋白-1基因突变引起 转化生长因子β信号转导，常导致主动脉瘤、夹层和死亡。有趣的是，相关的 主动脉管壁内的退变几乎总是发生在主动脉根部或升主动脉，而不是 降主动脉或腹主动脉；虽然这可能反映了血流动力学应力的区域差异， 单用降压治疗并不能有效控制MFS患者的主动脉瘤。或者，它也是 在这种情况下，占血管活性中层的主动脉平滑肌细胞(ASMC) 维管壁，有来自不同发育胚层的不同亚型，基于它们的 解剖位置：神经外胚层(NE)起源于上行的ASMCs和旁轴中胚层(PM) 起源导致ASMC的下降。该项目将使用原产地特定的ASMC，区别于诱导 来自MFS患者和健康对照组的多潜能干细胞(IPSCs)，以检验一种新的假设 发育起源导致与内侧退变相关的ASMCs的位置特异性异常 MFS。此外，还将探索马凡综合征症状前先天性缺陷的生物标志物 确定预防性治疗干预的新靶点。这些研究将表征表型 干细胞培养和血管培养条件下人ASMC亚型在细胞和组织水平的差异 组织工程技术。使用最先进的核心设施，我们还将进行转录和 对这些细胞和组织模型进行蛋白质组学分析以培养丰富的生物信息学 分析。此外，我们将开发一条生物信息学管道来阐明新的预防靶点。 对MFS引起的升主动脉中层变性负有内在责任，使用我们独特的组合 作为输入的表型、转录和蛋白质组结果。最后，基于我们的生物信息学输出，我们将 在我们的基于IPSC的人类体外模型上测试我们的干预，并与氯沙坦治疗进行比较 常用的抗高血压药物，也表现出独特的抗重构特性，并已显示出 承诺在动物和患者中管理MFS的症状。该奖学金的培训计划将 专注于技术技能、实验设计和批判性分析、对已发表的科学数据的批判性评价，以及 演讲技巧。它将通过定期的导师会议、期刊俱乐部、会议演示、双 年度委员会会议和高级课程。大部分培训将在科斯塔实验室进行，地点为 ISMMS心血管研究中心，一个高度活跃和协作的环境， 导师和学生与我的研究主题和职业目标保持一致。额外的培训将在 Ramirez实验室拥有马凡综合症和生化调查技术方面的高级研究人员。

PROJECT SUMMARY Marfan Syndrome (MFS), one of the most common heritable connective tissue disorders, affects 1 in 5,000 individuals and has destructive manifestations in multiple organ systems; notably the cardiovascular system. MFS is an autosomal dominant disease caused by a genetic mutation in the Fibrillin-1 gene leading to aberrant TGFβ signaling, and frequently results in aortic aneurysm, dissection, and death. Interestingly, the associated degeneration within the aortic vessel wall almost always occurs in the aortic root or ascending aorta and not in the descending or abdominal aorta; while this putatively reflects regional differences in hemodynamic stress, antihypertensive treatment alone is not effective in managing aortic aneurysm in MFS. Alternatively, it is also the case that aortic smooth muscle cells (ASMCs), which predominate the vasoactive medial layer of the vessel wall, have heterogeneous subtypes stemming from distinct developmental germ-layers based on their anatomical location; Neuroectoderm (NE) origin gives rise to ascending ASMCs and Paraxial mesoderm (PM) origin gives rise to descending ASMCs. This project will use origin-specific ASMCs differentiated from induced pluripotent stem cells (iPSCs) from patients with MFS and healthy controls to test a novel hypothesis that developmental origin causes location-specific abnormalities in ASMCs associated with medial degeneration in MFS. Additionally, it will explore for biomarkers of presymptomatic congenital defects in Marfan Syndrome to identify novel targets for prophylactic therapeutic intervention. These studies will characterize phenotypic differences in human ASMC subtypes at the cellular and tissue level with stem-cell culturing and vascular tissue engineering techniques. Using state-of-the-art core facilities we will also conduct transcriptomic and proteomic analysis on these cellular and tissue models to cultivate a rich biological profile for bioinformatic analysis. Furthermore, we will develop a bioinformatics pipeline to elucidate novel prophylactic targets inherently responsible for ascending aortic MFS-induced medial degeneration, using our uniquely combined phenotypic, transcriptomic, and proteomic results as input. Lastly, based on our bioinformatic outputs we will test our intervention on our human iPSC-based in vitro models and compare to treatment with Losartan, a commonly used anti-hypertensive drug that also exhibits unique anti-remodeling properties and has shown promise for managing the symptoms of MFS in animals and in patients. The training plan for this fellowship will focus on technical skills, experimental design and critical analysis, critique of published scientific data, and presentation skills. It will be achieved by regular mentor meetings, journal clubs, conference presentations, bi- annual committee meetings, and advanced coursework. The majority of training will occur in the Costa Lab at the Cardiovascular Research Center at ISMMS, a highly active and collaborative environment with available mentors and students aligned with my research topics and career goals. Additional training will occur in the Ramirez Lab with senior researchers in Marfan Syndrome and biochemical investigation techniques.