CAREER: ENGINEER A FUNCTIONAL 3-D VASCULAR NICHE TO SUPPORT NEURAL STEM CELL SELF-RENEWAL

1350240 DaiAdult neural stem cells（NSC）具有治疗神经系统损伤或疾病的巨大潜力。 然而，这些细胞是罕见的，难以在培养中维持，因为它们在从其天然环境中移除后很快失去其多能性。 在体内，神经干细胞居住在邻近的血管龛，这表明它可能是可能的，以维持这些细胞离体，如果血管龛的关键功能功能的特点是在培养environment.The假设提出的研究是，形成一个灌注，功能性血管内的3-D细胞外基质促进自我更新周围的神经干细胞。 为了检验这一假设，将追求以下具体目标：1）使用新的细胞打印技术在3-D基质内创建包含灌注的脉管系统和NSC的神经血管单元。 2)根据基质特性和培养参数，建立合成结构的成熟过程和功能。 3)检查神经干细胞的行为和细胞的命运，使用工程神经血管单位，并确定影响神经干细胞的命运和它的关系的功能状态的vascularis.Intellectual优点：拟议的研究将建立一个3-D灌注血管生态位研究神经干细胞在生理相关的实验系统，其中个别组件和参数可以很容易地操纵的关键因素。 使用这个系统，拟议的研究将定义关键因素，以实现功能的血管，并将阐明潜在的机制，神经干细胞自我更新的动态灌注系统。由于脉管系统是许多成体干细胞小生境的关键因素，因此这项研究将在研究其他干细胞领域中产生更广泛的影响。 总体而言，这项工作将确定打印结构的设计原则和操作参数，以支持体外周围组织的生长，从而为未来生物医学应用中制造适当厚度的组织奠定基础。拟议的研究在产生与3-D血管组织形成及其在调节NSC命运中的作用相关的基础知识方面具有更广泛的科学影响。 因此，拟议的研究有望帮助开发用于患者特异性NSC的体外扩增的方法，以治疗脊髓损伤和神经退行性疾病，这将使患者和整个社会受益。 研究将与针对K-12教育和代表性不足群体的教育和外联活动相结合。 展示工程师如何解决社会挑战的活动将激励学生追求科学和工程事业。

1350240DaiAdult neural stem cells (NSCs) have great potential for treating damage or disease of the nervous system. However, these cells are rare and difficult to maintain in culture because they quickly lose their multi-potency after being removed from their native environment. In vivo, NSCs reside adjacent to a vascular niche, suggesting that it may be possible to maintain these cells ex vivo if critical functional features of the vascular niche are recreated in the culture environment.The hypothesis of the proposed studies is that formation of a perfused, functional vasculature within 3-D extracellular matrix promotes self-renewal of the surrounding NSCs. To test this hypothesis, the following specific aims will be pursued: 1) Create a neurovascular unit that contains perfused vasculature and NSCs within 3-D matrix using a novel cell printing technology. 2) Establish the maturation process and functionalities of the synthesized structures with regard to matrix properties and culture parameters. 3) Examine the NSC behavior and cell fate using the engineered neurovascular unit; and determine critical factors that influence NSC fate and its relationship to the functional status of the vasculature.Intellectual Merit: The proposed research will build a 3-D perfused vascular niche to study NSCs in a physiologically relevant experimental system, in which individual components and parameters can be easily manipulated. Using this system, the proposed research will define critical factors to achieve functionality of the vasculature and will elucidate underlying mechanisms of NSC self-renewal in the dynamically perfused system. Since vasculature is a key element of many adult stem cell niches, this research will have broader ramifications in studying other stem cell fields. Overall, this work will identify design principles and operating parameters for the printed structures to support the growth of the surrounding tissues in vitro, and thereby lay the foundation to fabricate tissues of appropriate thickness for biomedical applications in the future.Broader Impacts: The proposed research has broader scientific impact in generating fundamental knowledge related to 3-D vascular tissue formation and its role in regulating NSC fate. Therefore, the proposed studies are expected to help develop methods for the ex vivo expansion of patient-specific NSCs to treat spinal cord injury and neurodegenerative diseases, which will benefit patients and the society at large. Research will be integrated with educational and outreach activities targeting K-12 education and underrepresented groups. Activities demonstrating how engineers can solve societal challenges will provide incentives to students to pursue careers in science and engineering.