Optically Promoting Cardiac Maturation Using Engineered Peptides

项目摘要 人类干细胞衍生的心肌细胞（hSC-CM）的前景为人类干细胞的发展打开了大门。 针对心脏疾病的个性化药物治疗的可行性，并进行更准确的药物治疗 发现研究此外，hSC-CM克服了使用动物时的物种差异问题， 用于高通量筛选研究的模型。然而，扩大使用的瓶颈之一是， hSC-CM是其准确反映成年人天然结构和功能的能力， 心肌细胞目前解决这一关键挑战的努力涉及成熟协议， 生物物理线索，如电刺激和机械刺激。这些方法通常使用电极 用于场刺激的触点，用于机械或持续化学刺激的大型仪器，或 基因改造细胞使其对光敏感。虽然我们已经看到了成功， 在诱导和刺激方法中，该领域将受益于刺激方法， 培养接触，以减少长期培养期间的感染风险，以及基于光的方法 具有比基于电极的刺激更高的时空分辨率。在这里，我们提出一个新的 通过将这些细胞与基于肽的 这些基底被设计成将光转换为电线索。我们的团队将开发肽 用发色团单元和细胞结合表位作为可用于 光电调节hSC-CM朝向成熟。该项目的长期目标是 通过工程肽建立光电调节作为电刺激的可行方法 心肌细胞和促进hSC-CM成熟的无电极和非遗传的方式， 比场刺激更高的时空分辨率。我们假设瞬时充电和其他 心肌细胞-生物材料界面的相关光诱导过程可以影响细胞外 电位，导致hSC-CM朝向成熟的光电刺激。我们的理由是 提出一种基于材料的方法来刺激hSC-CM源于以前的报告， 共轭聚合物用作光敏底物， 可兴奋细胞为了验证我们的假设，我们提出了以下具体目标：（1）建立设计 具有最佳光刺激效率的肽纳米组装体的参数;（2）测试细胞-和 肽介导的光刺激的组织水平的影响;和（3）阐明所提出的 光电调节方法对hSC-CM成熟的影响。通过建立设计规则， 提出了用于刺激hSC-CM并确保其局部激发hSC-CM的能力的光激发肽， 心脏细胞，这种创新的方法为心脏组织的“无线”刺激提供了新的策略 并且可以显著地有助于解决干细胞不成熟的巨大挑战。 1

PROJECT SUMMARY The promise of human stem cell-derived cardiomyocytes (hSC-CMs) opens doors towards the feasibility of personalized medicine against cardiac diseases and for performing more accurate drug discovery studies. Moreover, hSC-CMs overcome the issue of species differences when using animal models for high throughput screening studies. However, one of the bottlenecks for scaling up the use of hSC-CMs is their ability to accurately reflect the native structure and function of adult human cardiomyocytes. Current efforts to address this critical challenge involve maturation protocols that use biophysical cues such as electrical and mechanical stimulation. These methods often utilize electrode contacts for field stimulation, bulky instrumentation for mechanical or sustained chemical stimulation, or genetically modifying cells to be light-responsive. Although we have seen successes through these induction and stimulation approaches, the field would benefit from a stimulation approach with minimal culture contact to reduce risk of infection during long-term cultures, as well as a light-based approach with higher spatiotemporal resolution than electrode-based stimulation. Here, we propose a new paradigm for stimulating hSC-CMs towards maturation by interfacing these cells with peptide-based substrates that are engineered to convert light to electrical cues. Our team will develop peptides engineered with chromophore units and cell-binding epitopes as materials that can be used for photoelectrical conditioning of hSC-CMs towards maturation. The long-term goal of this project is to establish photoelectrical conditioning via engineered peptides as a viable method to electrically stimulate cardiomyocytes and promote hSC-CM maturation in an electrodeless and non-genetic manner, with higher spatiotemporal resolution than field stimulation. We hypothesize that transient charging and other associated light-induced processes at the cardiomyocyte-biomaterial interface can influence extracellular potential, resulting in the photoelectrical stimulation of hSC-CMs towards maturation. Our rationale for proposing a materials-based approach for stimulating hSC-CMs stems from previous reports of conjugated polymers being used as a photoactive substrate for triggering action potentials of other excitable cells. To test our hypothesis, we propose the following specific aims: (1) establishing design parameters for peptide nanoassemblies with optimal photostimulation efficiency; (2) test the cellular- and tissue-level impact of peptide-mediated photostimulation; and (3) elucidate the effect of the proposed photoelectrical conditioning method on hSC-CM maturation. By establishing the design rules for the proposed photoexcitable peptides for stimulating hSC-CMs and ensuring their capability to locally excite cardiac cells, this innovative approach offers a new strategy for a “wireless” stimulation of cardiac tissues and can significantly contribute towards addressing the grand challenge of stem cell immaturity. 1