CAREER:Injectable Biomimetic Scaffolds to Direct Stem Cell-Derived Cardiomyocyte Differentiation

1150854/Lipke PI的长期研究目标是对仿生材料推动干细胞来源的心肌细胞(SC-CM)电生理成熟的机制有一个基本的了解。这项职业研究计划使用一种新型的水凝胶微球包裹系统，为多能干细胞提供特定的信号，以指导其向心肌细胞分化，并在单细胞和组织水平上评估所得到的SC-CMS的功能电生理特性。使用目前的分化方法，干细胞-CM的成熟通常不会超过产前的表型，总体电生理特性差异很大。因此，皮？S研究计划的目标是检验以下假设：(1)仿生支架可用于提高SC-CMS的均质性，降低分化批次内和分化批次之间的电生理特性的变异性；(2)包括一氧化氮在内的信号分子的局部释放可用于提高SC-CM的成熟度；(3)SC-CMS的电生理特性将取决于它们所提供的分化环境，包括共聚物配方、培养时间和初始干细胞浓度的变化；(4)SC-CMS可通过与更成熟的新生心肌细胞直接偶联，促进工程化心肌组织的电信号传播。以下教育目标与PI的研究目标相结合：(1)在她的实验室保持1：1的本科生和研究生研究人员的比例；(2)让心脏护理专业的学生学习干细胞和心脏再生研究，以便他们更好地为教育患者做好准备；(3)将心血管研究相关的内容和项目纳入她的课程；(4)通过开展K-12推广活动，激励K-12学生追求科学和工程事业。(5)通过组织活动和一对一指导，支持女性和少数族裔留在科学和工程领域。智力优势：PI专注于表征和指导SC-CM电生理学，特别是对于在可扩展系统中区分或封装在生物材料支架中的SC-CM，预期结果将为该领域的其他人提供有价值的基础。从这些研究中获得的知识将被应用于可注射生物材料支架和工程化心脏组织的设计，以改善对心脏再生至关重要的电生理整合。建立对如何统一推进SC-CM电生理成熟度的基本了解，并利用这些信息开发控制批次间变异性的分化系统，对于降低SC-CM导致致命心律失常的可能性至关重要。此外，获得足够数量的同质细胞以形成组织是具有挑战性的。这项研究的跨学科性质利用并深化了我们在几个领域的基础知识，包括运输现象和热力学、电子信号处理和发育生物学。负面影响：心脏病是美国每年男性和女性的头号死因。提高修复受损或患病心脏的能力将为患者提供更长时间和潜在更好质量的生活机会。PI的研究结果将为教材提供基础，这些教材将被整合到她的核心本科课程和高级细胞和组织工程课程中。心脏护理专业的学生在他们的职业生涯中将成为重要的健康教育者，他们也将来到PI的实验室学习干细胞和心脏再生的研究。指导本科生研究人员将继续是国际学生联合会的优先事项，她将扩大努力，吸引来自代表性不足群体的学生。为了让K-12的学生参与这项研究，并培养他们追求科学和工程事业的兴趣，PI将使用现有的成功框架，包括奥本大学的青年科学体验(YES)夏令营和GOTS计划(GUTS)。

1150854/ LipkeThe PI's long-term research goal is to develop a fundamental understanding of the mechanisms by which biomimetic materials can drive electrophysiological maturation of stem cell-derived cardiomyocytes (SC-CMs). This CAREER research plan uses a novel hydrogel microsphere encapsulation system to provide pluripotent stem cells with specific cues to direct their differentiation into cardiomyocytes and assesses the functional electrophysiological properties of resulting SC-CMs at the single cell and tissue levels. Using current differentiation methods, SC-CM maturation typically does not progress beyond a prenatal phenotype and overall electrophysiological properties vary greatly. Therefore, the objective of the PI?s research plan is to test the following hypotheses: (1) biomimetic scaffolds can be used to increase the homogeneity of SC-CMs and decrease variability in electrophysiological properties both within and between differentiation batches; (2) localized release of signaling molecules, including nitric oxide, can be used to enhance SC-CM maturity; (3) electrophysiological properties of SC-CMs will depend on the differentiation environment they are provided including variations in copolymer formulation, culture time, and initial stem cell concentration; and (4) SC-CMs will enhance electrical propagation through engineered cardiac tissues by directly coupling with more mature neonatal ventricular-derived cardiomyocytes. The following educational goals are integrated with the PI's research objective: (1) maintain a 1:1 ratio of undergraduate to graduate student researchers in her laboratory; (2) engage cardiac nursing students in learning about stem cell and cardiac regeneration research so they are better prepared to educate patients; (3) incorporate cardiovascular research-related content and projects into her coursework; (4) inspire K-12 students to pursue science and engineering careers through conducting K-12 outreach (5) support women and minority retention in science and engineering through organizational activities and one-on-one mentoring.Intellectual Merit: The PI's focus on characterizing and directing SC-CM electrophysiology is unique, particularly for SC-CMs differentiated in scalable systems or encapsulated in biomaterial scaffolds, and the anticipated results will provide a valuable foundation for others in the field. Knowledge gained from these studies will be applied to the design of injectable biomaterial scaffolds and engineered cardiac tissues to improve electrophysiological integration, which is essential for cardiac regeneration. Establishing a fundamental understanding of how to uniformly progress SC-CM electrophysiological maturity and using this information to develop differentiation systems that control batch-to-batch variability is critical to reducing SC-CM's potential to cause deadly arrhythmias. In addition, obtaining sufficient numbers of homogeneous cells to form tissues is challenging. The interdisciplinary nature of this research draws on and furthers our knowledge of fundamentals in several fields including transport phenomena and thermodynamics, electrical signal processing, and developmental biology.Broader Impacts: Heart disease is the number one cause of death in the United States each year for both men and women. Improving the ability to repair damaged or diseased hearts will provide patients the opportunity for both a longer and potentially better quality of life. The results of the PI's research will provide the foundation for educational materials that will be integrated into her core undergraduate courses and upper level cell and tissue engineering course. Cardiac nursing students, who in their careers will be important health educators, will also come to the PI's lab to learn about stem cell and cardiac regeneration research. Mentoring undergraduate researchers will continue to be a priority the PI, and she will expand her efforts to engage students from underrepresented groups. To engage K-12 students in this research and foster their interest in pursuing a career in science and engineering, the PI will use existing, successful frameworks including Auburn University's Youth Experience in Science (YES) camps and Getting Under the Surface (GUTS) program.