CAREER: Engineering Three-dimensional Stem Cell Niche with Independently Tunable Biochemical and Mechanical Properties

职业：设计具有独立可调的生化和机械特性的三维干细胞生态位

• 批准号: 1351289
• 负责人: Fan Yang
• 金额: $ 40万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-03-15 至 2019-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1351289&HistoricalAwards=false
• 关键词: CAREER; Engineering; Three; dimensional; Stem

1351289YangThe overall goal of this project is to develop a novel stem cell niche with biochemical and mechanical properties, which can be tuned independently; and to use this niche to elucidate how signals influence stem cell fate in three dimensions using high-throughput strategies.Intellectual meritStem cells have the potential to revolutionize medical therapies for a number of diseases. However, directing stem cell fate so that they maintain pluripotency or mutlipotency, or they commit to a certain differentiation lineage, is a critical problem in tissue engineering and regenerative medicine. Although there is ample evidence that stem cells respond to both biochemical and mechanical cues, understanding how the totality of signals in a given environment directs cell fate remains a largely unanswered question, especially in three dimensions (3D). Recent studies from the PI's laboratory indicate that biochemical and mechanical cues interact in a non-intuitive manner to regulate stem cell fate, which cannot be predicted from stem cell responses to individual type of niche cues. The proposed studies are designed to advance the understanding of stem cell-niche interactions by pursuing the following research objectives:Objective 1. Synthesize degradable polymers as biochemical and mechanical "building blocks" of stem cell niche that can crosslink simultaneously and independently to form an interpenetrating network.Objective 2. Develop biomimetic hydrogel microarrays with independently tunable nicheproperties for encapsulating cells in 3D.Objective 3. Examine the effects of interactive niche signaling on stem cell differentiation in 3D combinatorial hydrogel microarrays in a high-throughput manner.The systematic and combined approach implemented by the PI has a high intellectual merit. Additionally, the proposed studies carry multiple innovative features including the development of interpenetrating network hydrogels with independent control of biochemical and mechanical cues; AFM and FRET-based assays for high-throughput characterization of hydrogel stiffness and degradation; and novel microfabrication platforms and high-throughput screening assays for rapid monitoring of stem cell fate in 3D.Broader ImpactsThe proposed development of biomimetic hydrogel microarrays with independently tunable cues is expected to comprise a powerful tool to advance the fundamental understanding of stem cell-niche interactions in 3D, thus addressing a critical problem in stem cell biology and tissue engineering. The outcomes of the proposed research may greatly accelerate stem cell-based therapies by rapidly identifying optimal cues to direct stem cells into maintaining pluripotency or differentiating into functional mature cells. Ongoing and new educational plans target students from kindergarten to undergraduates. An outreach program for local elementary school K-G1 students, called "The Magic of Repairing Human Body," will be developed. The PI will also develop a one-week summer camp for high school students on "Tissue Engineering Fiesta, which will include interactive lectures, journal clubs and hands-on activities and will be geared towards high school students from underprivileged and minority background in the San Francisco Bay Area. Overall, the PI addresses a challenging problem with broader implications and has demonstrated commitment towards educational and outreach activities with local schools with diverse student populations.

1351289杨这个项目的总体目标是开发一种具有生化和机械特性的新型干细胞利基，它可以独立调整；并利用这个利基通过高通量策略从三维角度阐明信号如何影响干细胞的命运。智能价值干细胞具有革新多种疾病的医疗疗法的潜力。然而，控制干细胞的命运，使其保持多能性或多能性，或者致力于某种分化谱系，是组织工程和再生医学中的一个关键问题。尽管有充分的证据表明干细胞对生化和机械信号都有反应，但理解给定环境中的所有信号如何指导细胞命运在很大程度上仍然是一个悬而未决的问题，特别是在三维(3D)方面。PI实验室最近的研究表明，生化和机械信号以一种非直观的方式相互作用来调节干细胞的命运，这不能从干细胞对个别类型的利基信号的反应中预测出来。本研究旨在通过追求以下研究目标来促进对干细胞-生态位相互作用的理解：目的1.合成可降解聚合物作为干细胞生态位的生化和机械“构建块”，可以同时独立地交联形成互穿网络。目的2.开发具有独立可调生态位特性的仿生水凝胶微阵列，将细胞包裹在3D中。目的3.以高通量的方式研究三维组合水凝胶微阵列中相互作用的生态位信号对干细胞分化的影响。此外，拟议的研究具有多个创新特征，包括开发独立控制生化和机械线索的互穿网络水凝胶；基于AFM和FRET的水凝胶硬度和降解高通量表征分析；以及用于快速监测3D干细胞命运的新型微制造平台和高通量筛选分析。这项拟议研究的结果可能会极大地加速基于干细胞的治疗，因为它可以快速找到最佳线索，指导干细胞保持多能性或分化为功能成熟的细胞。正在进行的和新的教育计划针对从幼儿园到本科生的学生。将为当地小学的K-G1学生开发一个名为“修复人体的魔力”的外展项目。国际组织还将为高中生开发一个为期一周的“组织工程嘉年华”夏令营，其中将包括互动讲座、日记俱乐部和实践活动，面向旧金山湾区贫困和少数族裔背景的高中生。总的来说，国际组织解决了一个具有更广泛影响的具有挑战性的问题，并展示了与拥有不同学生群体的当地学校开展教育和外联活动的承诺。