Multi-Scale In Vitro 3D Tissue Model of Vascularized Bone-Cartilage Interactions

摘要 目前的血管化骨组织的体外模型不能模拟体内的微环境，包括 不同类型的细胞通过基质屏障相互沟通。此外，他们还受到阻碍 缺乏对血管-骨以及骨-软骨相互作用的实时可视化和量化。在……里面 相比之下，动物模型虽然提供有用的信息，但既耗时又昂贵，而且近年来， 越来越多地引起了人们对道德的担忧。此外，动物研究提供了有限的了解 机械行为与控制良好的体外研究的比较。因此，对体外培养的需求还没有得到满足。 用于改进血管化骨-软骨相互作用的监测和分析的平台。 我们建议开发和展示一种多尺度的血管化骨-软骨组织模型 对细胞信号的理解，第一阶段的重点是内皮细胞与骨之间的相互作用 细胞，特别是成骨细胞(骨构建细胞)和破骨细胞(骨降解细胞)和软骨细胞 (软骨细胞)。拟议办法的多尺度性质是基于使用(A)微尺度 基于微流体和组织工程学的血管骨-软骨模型研究细胞信号转导 提供(B)询问工程结构和天然结构的中尺度血管骨-软骨模型 用于结构和功能研究的组织。 第一阶段将清楚而毫不含糊地展示这种多尺度血管模型的使用。 骨软骨组织与细胞信号的相互作用。开发的平台将模拟形态， 体内观察到的生理流动和3D多细胞成分，并使系统变得简单和强大 用于评估细胞反应。在第二阶段，平台将扩大到包括其他基质细胞 (例如，成纤维细胞)和免疫细胞(例如，巨噬细胞)，然后详细描述信号 分子和治疗性筛选。具有以下专长的多学科产学研合作关系 基于微流控细胞的检测、肌肉骨骼生物学和组织再生 为顺利完成这一项目，已经组装完毕。通过提供准确、定量和 生理相互作用的预测模型，开发的多尺度平台有望建立一个新的 治疗药物生理反应的体外评估范例。

Abstract Current in vitro models of vascularized bone tissues do not mimic the in vivo microenvironment comprising of diverse cell types in communication with each other through stromal barriers. In addition, they are hampered by lack of real-time visualization and quantitation of vasculature-bone as well as bone-cartilage interactions. In contrast, animal models while providing useful information are time consuming, expensive and in recent years, have increasingly raised ethical concerns. Furthermore, animal studies provide limited understanding of mechanistic behavior compared to well-controlled in vitro studies. Thus, there is an unmet need for an in vitro platform for improved monitoring and analysis of vascularized bone-cartilage interactions. We propose to develop and demonstrate a multi-scale model of vascularized bone-cartilage tissue for the understanding of cellular signaling with a Phase I focus on the interactions between endothelial cells, bone cells, specifically osteoblasts (bone-building cells) and osteoclasts (bone-degrading cells), and chondrocytes (cartilage cells). The multi-scale nature of the proposed approach is based on the use of (a) a microscale based vascular bone-cartilage model using microfluidics and tissue engineering to study cell signaling, which informs (b) a meso-scale vascular bone-cartilage model interrogating both engineered constructs and native tissues for structural and functional studies. Phase I will clearly and unequivocally demonstrate the use of this multiscale model of vascularized osteochondral tissue interactions for cell signaling. The developed platform will mimic the morphology, physiological flow and 3D multi-cellular compositions observed in vivo and enable an easy and robust system for evaluation of cellular responses. In Phase II, the platform will be expanded to include other stromal cells (e.g., fibroblasts), and immune cells (e.g., macrophages), followed by detailed characterization of the signaling molecules and therapeutic screening. A multi-disciplinary industry-academic partnership with expertise in microfluidics cell based assays and musculoskeletal biology and tissue regeneration has been assembled for successful completion of this project. By providing an accurate, quantitative and predictive model of physiological interactions, the developed multi-scale platform promises to establish a new paradigm for in vitro assessment of the physiological response to therapeutics.