Biodegradable Matrices with Structural and Physical Cues for Interface Engineering

响应于生物材料线索的干细胞谱系承诺为复杂的细胞分化提供了有吸引力的替代手段。 组织再生这个项目的目标是设计，开发和评估一个脚手架平台， 通过材料硬度和生物物理线索在3D微环境中指导干细胞。我们建议 评估这种支架技术，以研究骨软骨（OC）组织的发展与界面作为一个潜在的 复杂组织修复的解决方案，满足临床需求。OC组织再生仍然是一个主要的 尽管有许多优点，但目前的生物和组织工程移植物未能提供成功的 长期临床结果。组织再生不完全，新形成的软骨质量 （纤维软骨/透明）和缺乏带状结构形成导致宿主组织整合不良。当前 组织工程学的知识阐明了生物材料的作用及其表面形式的线索 化学、拓扑学和基质硬度在2D培养中调节干细胞命运和谱系定型中的作用。 然而，已经做出有限的努力来将材料和结构线索结合到3D支架中以诱导细胞凋亡。 干细胞谱系定型本提案的主要目标是开发一种脚手架平台， 注入结构和材料线索来驱动间充质干细胞（MSC）谱系定型、分化， 和带状结构形成以再生OC组织。我们最近的出版物和未出版的工作表明， 在体外和体外条件下，通过培养的MSC在支架结构内形成层状OC组织， 体内条件。目前的支架技术是创新的，因为它使用单一材料来创建孔隙 区域配置中的梯度，以避免材料兼容性问题和分层。另夕h 文献缺乏方法来表征带状组织，如OC和支架，在此提出的。 应用程序.我们建议开发和验证热图方法作为一种新的分析工具来衡量 材料硬度和验证定量与组织学发现再生组织从体外和体内 体内样品。我们假设，支架结构充满了不同的基质刚度和生长因子， 将促进植入的成体干细胞分化为完全OC组织再生， 结构该项目的具体目标是：目标1：优化嵌入有 界面工程的结构和物理线索。目的2：阐明生物材料与细胞的相互作用， 局部基质硬度和结构在影响体外MSC谱系定型中的机械作用。目标3： 在兔模型中评估具有OC界面形成的生物物理线索的工程支架系统。的 该项目的结果可能导致（i）开发使能的支架技术以工程化干细胞， 和（ii）开发OC试验台支架平台，促进带状结构形成， 组织整合脚手架技术，工具和方法，通过这个项目的发展将是 适用于构建接口工程的支架驱动再生策略。

Stem cell lineage commitment in response to biomaterial cues offer attractive alternative means for complex tissue regeneration. The goal of this project is to design, develop, and evaluate a scaffold platform that can instruct stem cells in a 3D micro-environment through material stiffness and bio-physical cues. We propose to evaluate this scaffold technology to study osteochondral (OC) tissue development with an interface as a potential solution to complex tissue repair, an unment clinical need. The OC tissue regeneration continues to be a major clinical hurdle and despite many merits, current biological and tissue engineered grafts fail to provide successful long-term clinical outcomes. Incomplete tissue regeneration, quality of newly formed cartilage (fibrocartilage/hyaline), and lack of zonal structure formations lead to poor host tissue integration. The current knowledge in tissue engineering elucidates the role of biomaterials and their cues in the form of surface chemistry, topography, and matrix stiffness in regulating stem cell fate and lineage commitment in 2D cultures. However, limited efforts have been made to incorporate material and structural cues in 3D-scaffolds to induce stem cell lineage commitment. The primary objective of this proposal is to develop a scaffold platform with imbued structural and material cues to drive mesenchymal stem cell (MSC) lineage commitment, differentiation, and zonal structure formation to regenerate OC tissue. Our recent publications and unpublished work suggest layered OC tissue formation within the scaffold structure by the cultured MSCs under controlled in vitro and in vivo conditions. The current scaffold technology is innovative because it uses a single material to create pore gradients in zonal configurations to avoid material compatibility issues and delamination. Additionally, the literature lacks methodology to characterize a zonal tissue such as OC and scaffolds presented in this application. We propose to develop and validate a heat map methodology as a new analytical tool to measure material stiffness and validate quantitatively with histological findings of regenerated tissue from in vitro and in vivo samples. We hypothesize that scaffold architecture imbued with varied matrix stiffness and growth factors will promote implanted adult stem cell differentiation towards complete OC tissue regeneration with zonal structure. The specific aims of this project are: Aim 1: Optimization of a 3D-scaffold platform embedded with structural and physical cues for interface engineering. Aim 2: Elucidate biomaterial-cell interactions and the mechanistic role of local matrix stiffness and structure in influencing MSC lineage commitment in vitro. Aim 3: Assess the engineered scaffold system with bio-physical cues for OC interface formation in a rabbit model. The outcomes of this project may lead to (i) development of an enabling scaffold technology to engineer stem cells, and (ii) development of an OC test-bed scaffold platform that promotes zonal structure formation leading to host tissue integration. The scaffold technology, tools, and methodologies developed through this project will be applicable to build scaffold-driven regenerative strategies for interface engineering.