Physiologic stress in advanced tissue culture models of cardiomyopathy

项目总结/摘要 多种形式的肌营养不良症的特征在于心脏受累，这可能危及生命， 包括杜氏肌营养不良（DMD）和LMNA相关的肌营养不良。这些疾病是 分别由DMD和LMNA突变引起。心力衰竭是发病的主要原因， 这些疾病的死亡率。骨骼肌和心肌中的生理机械应力是骨骼肌和心肌收缩的主要驱动力。 这些形式的肌肉萎缩症。此外，心律失常，不成比例的左 心室功能障碍在LMNA相关疾病中是突出的。新的治疗策略，如外显子 跳跃，基因治疗和CRISPR-Cas9基因编辑正在开发或已被批准用于这些领域。 疾病患者特异性诱导多能干细胞可被创建并分化为心肌细胞 （iPSC-CM），提供了在培养皿中研究患者特异性突变和测试治疗方法的机会。 然而，iPSC-CM受到组织不成熟、非生理应激源和非生理输出的限制。 工程心脏组织是通过在水凝胶基质中接种iPSC-CM来创建的，所述水凝胶基质由柔性支架支撑。 岗位利用这些组织构建体，可以实现更高级程度的细胞成熟，并且 可以容易地确定诸如收缩速度和幅度的输出。K 08奖项的具体目标1 目的评估生理机械应力对iPSC-CM的影响。具体目标2将改善 使用患者来源的血管内皮细胞评估新型工程化心脏组织构建物的促血管生成潜力 携带DMD和LMNA突变的iPSC-CM。将评估两种疾病实体的新疗法。 初步数据表明DMD iPSC-CM对机械损伤的敏感性增加。 应激和通过新治疗减轻这种表型。一种工程心脏组织原型， 提出了将允许这些组织的直接电生理询问。我们预计这一 原型，这将允许更均匀的起搏，将是有用的，特别是在表征新的治疗， 对LMNA iPSC-CM的影响。该K 08将支持PI Dominic Fullenkamp的职业发展计划 医学博士，他接受了生物医学工程的研究生培训，是内科医生兼科学家心脏病学家。 博士Fullenkamp的长期目标是成为一名独立的研究者，作为一名医生科学家， 心血管生物学和工程学的接口，并使用该接口来测试新的治疗方法。在 除了所提议的研究外，Fullenkamp博士还打算利用这一奖项进一步发展他在以下方面的培训： 心血管生物学在伊丽莎白麦克纳利医学博士和阿尔弗雷德乔治医学博士的指导下， 经验丰富和合作的导师，在西北大学。他的发展计划将得到 与他的研究兴趣直接相关的内部和外部课程和临床活动。

PROJECT SUMMARY/ABSTRACT Multiple forms of muscular dystrophy are characterized by cardiac involvement which can be life-threatening, including Duchenne muscular dystrophy (DMD) and LMNA-related muscular dystrophy. These diseases are caused by mutations in DMD and LMNA, respectively. Heart failure is a leading cause of morbidity and mortality in these diseases. Physiologic mechanical stress in skeletal and cardiac muscle is a main driver of disease in these forms of muscular dystrophy. In addition, cardiac arrhythmias, disproportionate to left ventricular dysfunction, are prominent in LMNA-related disease. New therapeutic strategies, such as exon skipping, gene therapy, and CRISPR-Cas9 gene editing, are in development or have been approved for these diseases. Patient-specific induced pluripotent stem cells can be created and differentiated into cardiomyocytes (iPSC-CMs), offering the opportunity to study patient-specific mutations and test therapeutics in the dish. However, iPSC-CMs are limited by tissue immaturity, non-physiologic stressors, and non-physiologic outputs. Engineered heart tissues are created by seeding iPSC-CMs in a hydrogel matrix that is supported by flexible posts. With these tissue constructs, a more advanced degree of cellular maturation can be achieved, and outputs such as contraction velocity and amplitude can be readily determined. Specific Aim 1 of this K08 award aims assess the effect of physiologic mechanical stress on iPSC-CMs. Specific Aim 2 will improve the assessment of arrhythmogenic potential in novel engineered heart tissue constructs using patient-derived iPSC-CMs harboring DMD and LMNA mutations. Novel therapeutics for both disease entities will be assessed. Preliminary data is presented that demonstrates increased susceptibility of DMD iPSC-CMs to mechanical stress and mitigation of this phenotype by a novel therapeutic. An engineered heart tissue prototype is presented that will allow for the direct electrophysiologic interrogation of these tissues. We expect this prototype, which will allow for more uniform pacing, will be useful, especially in characterizing novel therapeutic effects on LMNA iPSC-CMs. This K08 will support the career development plan for the PI, Dominic Fullenkamp MD PhD, who received his graduate training in biomedical engineering and is physician-scientist cardiologist. Dr. Fullenkamp's long-term objective is to become an independent investigator as a physician scientist at the interface of cardiovascular biology and engineering, and use this interface to test novel therapeutics. In addition to the research proposed, Dr. Fullenkamp aims to use this award to further develop his training in cardiovascular biology under the mentorship of Elizabeth McNally MD PhD and Alfred George MD, two experienced and collaborative mentors, at Northwestern University. His development plan will be supported by internal and external coursework and clinical activity that directly correlates with his research interests.