Substrate Independent, Spatially Resolved, Stable Polymer Coatings for Studying Human Mesenchymal Stem Cells (hMSCs)

用于研究人间充质干细胞 (hMSC) 的基底独立、空间分辨、稳定的聚合物涂层

• 批准号: 1306482
• 负责人: Padma Gopalan
• 金额: $ 39万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1306482&HistoricalAwards=false
• 关键词: Substrate; Independent; Spatially; Resolved; Stable

This award by the Biomaterials program in the Division of Materials Research is a three-year plan of integrated research, education, and outreach on a polymeric coating for studying human mesenchymal stem cells (hMSCs). This award is cofunded by the Polymer program in the Division of Materials Research. Earlier studies strongly indicate that hMSC phenotype is strongly influenced by ligands derived from the natural cellular microenvironment, including cell adhesion peptides, heparin-binding peptides, and growth factor-mimetic peptides. This proposal is to develop polymer coatings based on copolymers of poly(ethylene glycol) with at most 10% of crosslinkable groups, which can be crosslinked into 30 nm mats for immobilization of peptides. These mats are chemically-defined for stable presentation of two putative pro-osteogenic peptides over an extended timeframe, and to explore in depth the effects on hMSC differentiation into osteoblasts. These polymer coatings with peptides present a stable cytophobic slate, and hence one can truly investigate the effect of the relevant peptides on hMSCs during the entire time course of osteogenic differentiation. Importantly, these coatings are thin films that can be applied to virtually any underlying substrate, which will lead to broad impact on cell culture studies and future design of biomedical devices. Because of the thin-film nature, the proposed use of X-ray photoelectron spectroscopy will quantify precisely the peptides presented on the polymer coatings. Further, this proposal will study the first systematic analysis of chemically defined, nanometer-scale presentation of a growth factor-receptor binding ligand, and it may lead to broad impact in view of the importance of receptor dimerization/clustering in virtually all growth factor signaling systems. The technological broader impact of this proposal would be in developing a new class of ultra-thin biomaterial coatings with unique set of properties for stem cell growth. In order to clearly understand the effects of micro environmental signals on stem cell behavior, there is a critical need for experimental systems that present specific signals, and complex signal combinations, to stem cells. The proposed platform may lead to widespread use of the proposed approaches by cell biologists in general. Ultimately, this line of research could result in identification of signals that promote lineage-specific stem cell differentiation, leading to development and optimization of substrates that promote stem cell differentiation in vitro and in vivo. More generally, the proposed adaptable and chemically tailorable thin films would be applicable to a broad range of fundamental questions in cell biology in which stable, controlled presentation of peptide ligands is desirable. As part of this grant, this project will: 1) develop Interdisciplinary Curriculum Development of two courses in two departments, one based in Materials Science & Engineering, and the second one based in Biomedical Engineering; 2) carry out dissemination and outreach activities by the development of hands-on exhibits on Stem Cells and Tissue Engineering that would provide case study materials for a Science and Social Media course; and 3) recruit and mentor female and underrepresented minority graduate and undergraduate students in research activities.

该奖项由材料研究部的生物材料计划颁发，是一项为期三年的综合研究，教育和推广聚合物涂层的计划，用于研究人类间充质干细胞（hMSCs）。该奖项由材料研究部的聚合物项目共同资助。早期的研究强烈表明，hMSC表型受到来自天然细胞微环境的配体的强烈影响，这些配体包括细胞粘附肽、肝素结合肽和生长因子模拟肽。该建议是开发基于具有至多10%的可交联基团的聚（乙二醇）的共聚物的聚合物涂层，其可以交联成30 nm的垫用于肽的固定。 这些垫在化学上被定义为在延长的时间范围内稳定呈递两种推定的促成骨肽，并深入探索对hMSC分化成骨细胞的影响。这些具有肽的聚合物涂层呈现稳定的细胞疏水性状态，因此可以真正研究相关肽在成骨分化的整个时间过程中对hMSC的影响。重要的是，这些涂层是可以应用于几乎任何底层基底的薄膜，这将对细胞培养研究和生物医学设备的未来设计产生广泛的影响。由于薄膜的性质，建议使用X射线光电子能谱法将精确定量的聚合物涂层上的肽。此外，该提案将研究化学定义的，纳米级的生长因子受体结合配体的介绍的第一个系统的分析，它可能会导致广泛的影响，在几乎所有的生长因子信号系统中的受体二聚化/集群的重要性。该提案的技术更广泛的影响将是开发一类新的超薄生物材料涂层，具有独特的干细胞生长特性。为了清楚地了解微环境信号对干细胞行为的影响，迫切需要向干细胞呈现特定信号和复杂信号组合的实验系统。所提出的平台可能会导致细胞生物学家广泛使用所提出的方法。最终，这一系列研究可能会导致识别促进谱系特异性干细胞分化的信号，从而开发和优化促进体外和体内干细胞分化的底物。更一般地说，所提出的适应性和化学可剪裁的薄膜将适用于细胞生物学中的广泛的基本问题，其中稳定的，受控的肽配体的呈现是理想的。作为该补助金的一部分，该项目将：1）在两个部门开发两门课程的跨学科课程开发，一门基于材料科学&工程，另一门基于生物医学工程; 2）通过开发干细胞和组织工程的实践展览开展传播和外联活动，为科学和社会媒体课程提供案例研究材料;以及3）在研究活动中招募和指导女性和代表性不足的少数民族研究生和本科生。