Biomimetic Ligand Display in Proteolipobead Hybrid Matrices to Direct Stem Cell Chondrogenesis

蛋白脂珠混合基质中的仿生配体展示指导干细胞软骨形成

• 批准号: 1207480
• 负责人: M Lane Gilchrist
• 金额: $ 44万
• 依托单位: CUNY City College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1207480&HistoricalAwards=false
• 关键词: Biomimetic; Ligand; Display; Proteolipobead; Hybrid

ID: MPS/DMR/BMAT(7623) 1207480 PI: Gilchrist, Lane ORG: CUNY City CollegeTitle: Biomimetic Ligand Display in Proteolipobead Hybrid Matrices to Direct Stem Cell ChondrogenesisINTELLECTUAL MERIT: Mimicking elements of stem cell microenvironments to elicit regenerative control is one of the major challenges in biomaterials research. Of the major environmental cues, the presentation of membrane associated ligands involved in cell-cell interactions (e.g. cadherin, notch) and the sequestering of soluble factors (e.g. transforming growth factor-beta) at the cell surface have not yet been well established in 3D culture systems. As the 3D context is more appropriate for biomimicry of the stem cell niche, our long-term goal is to integrate microsphere-supported biomembrane systems into 3D matrices. This will be accomplished using a composite 3D hydrogel scaffold architecture that integrates laterally mobile ligands/bound factors positioned in microsphere-supported biomembrane systems known as proteolipobeads. For the first time, this will allow for the laterally mobile presentation of various ligands/membrane-bound factors to stem cells within a 3D format via novel, molecularly engineered interfaces with controlled surface densities. Thus, the specific focus of this proposal is to build a platform that incorporates laterally mobile N-Cadherin fragments and the TGF-beta3 receptor, TGF-beta-R3 (i.e., beta-glycan), in proteolipobeads suspended in a 3D matrix for presentation to human mesenchymal stem cells (hMSCs). The proposed mode of N-cadherin and TGF-beta-R3 display will be used to investigate the effects of N-cadherin-mediated cell-cell communication events and TGF-beta3 sequestering on MSC chondrogenesis in vitro and serve as the proof-of-concept for this transformative technology. The specific hypothesis behind the proposed research is that the introduction of proteolipobead assemblies into 3D scaffolds is a viable biomimetic means to present ligands/bound factors to stem cells and mimic cellular communication in the stem cell niche. The objectives are designed to examine if this mode of ligand presentation can be achieved and to assess the effects on stem cell viability and differentiation. Objective 1 is to embed N-cadherin/TGF-beta-R3 proteolipobeads in carboxymethylcellulose 3D constructs and probe N-Cadherin display and TGF-beta3 growth factor sequestration. Objective 2 is to investigate the interaction between N-cadherin/TGF-beta-R3 biomembrane-microspheres and hMSCs by monitoring MSC viability and chondrogenic differentiation.BROADER IMPACTS: The benefits to society of the proposed activity are that contributions from the research could help cross major technological barriers in stem cell bioengineering, so that humanity can ultimately guide stem cell regeneration processes. Essentially a whole dimension in stem cell ligand/bound factor presentation has not yet been achieved, and the proposed scaffold design may lead to new molecular methods for control of stem cells in 3D culture. In addition, this work may lead to innovative therapies for cartilage repair, which is a significant clinical problem. To go beyond the impact of the research outcomes, we will implement a new mechanism for advancing discovery while promoting training and learning. This program will be specifically tailored to inner-city middle and high school students and aimed at stimulating a fascination with the molecular basis for color. This educational outreach integrates UV-VIS pigment identification field studies of sanctioned and renegade street graffiti art in the CCNY (Harlem) neighborhood. A concurrently running online dye and pigment database will be created, that will be further augmented with molecular structure and absorption-relevant molecular orbital visualizations using computational chemistry packages. The very same pigments, dyes, and fluorophores have dual uses in paints and as molecular reporter groups in the proposed studies. Thus, the participating labs are well positioned to provide the initial research setting along this learning pathway for local students who take an interest in the molecular basis of color. The results of this research in stem cell biomaterial engineering will be broadly disseminated via oral presentations at conferences, and in regular student research poster symposia at CCNY.

ID：MPS/DMR/BMAT（7623）1207480 PI：吉尔克里斯特，莱恩 ORG：CUNY City CollegeTitle：仿生配体展示在蛋白脂质体珠混合基质中指导干细胞软骨发生智力优势：模拟干细胞微环境的元素以引发再生控制是生物材料研究的主要挑战之一。 在主要的环境线索中，参与细胞-细胞相互作用的膜相关配体（例如钙粘蛋白、notch）的呈递和可溶性因子（例如转化生长因子-β）在细胞表面的隔离尚未在3D培养系统中很好地建立。 由于3D环境更适合干细胞生态位的仿生学，我们的长期目标是将微球支撑的生物膜系统整合到3D矩阵中。 这将使用复合3D水凝胶支架结构来实现，该结构整合了位于微球支持的生物膜系统（称为蛋白脂质珠）中的横向移动的配体/结合因子。 这将第一次允许通过具有受控表面密度的新型分子工程界面在3D格式内将各种配体/膜结合因子横向移动的呈递给干细胞。 因此，该提议的具体焦点是构建一个平台，其并入横向移动的N-钙粘蛋白片段和TGF-β 3受体TGF-β-R3（即，β-聚糖），在悬浮于3D基质中的蛋白脂质珠粒中用于呈递给人间充质干细胞（hMSC）。 提出的N-钙粘蛋白和TGF-β-R3展示模式将用于研究N-钙粘蛋白介导的细胞间通讯事件和TGF-β 3螯合对体外MSC软骨形成的影响，并作为这种变革技术的概念验证。 提出的研究背后的具体假设是，将蛋白脂质珠组装体引入3D支架是一种可行的仿生手段，可以将配体/结合因子呈递给干细胞并模拟干细胞龛中的细胞通讯。 目的是检查是否可以实现这种配体呈递模式，并评估对干细胞活力和分化的影响。 目的1：将N-cadherin/TGF-β-R3蛋白脂质微球包埋在羧甲基纤维素3D构建体中，并探测N-cadherin展示和TGF-β 3生长因子螯合。 目的二是通过监测MSC的活力和软骨分化，研究N-cadherin/TGF-β-R3生物膜微球与hMSCs之间的相互作用。更广泛的意义：这项研究对社会的益处在于，它可以帮助跨越干细胞生物工程的主要技术障碍，使人类最终能够指导干细胞再生过程。 基本上，干细胞配体/结合因子呈递的整个维度尚未实现，并且所提出的支架设计可能导致用于在3D培养中控制干细胞的新的分子方法。 此外，这项工作可能会导致软骨修复的创新疗法，这是一个重要的临床问题。 为了超越研究成果的影响，我们将实施一种新的机制，在促进培训和学习的同时推进发现。 该计划将专门为市中心的初中和高中学生量身定制，旨在激发对颜色分子基础的迷恋。 这一教育推广活动整合了对CCNY（哈莱姆）社区认可和重新认可的街头涂鸦艺术的紫外-可见色素识别实地研究。 将创建一个同时运行的在线染料和颜料数据库，该数据库将使用计算化学软件包进一步增强分子结构和吸收相关的分子轨道可视化。 同样的颜料，染料和荧光团在油漆中具有双重用途，并在拟议的研究中作为分子报告基团。 因此，参与实验室的位置很好，以提供初步的研究设置沿着这一学习途径，为当地学生谁采取了颜色的分子基础的兴趣。 这项研究在干细胞生物材料工程的结果将通过口头报告在会议上广泛传播，并在定期的学生研究海报研讨会在CCNY。