(Re)vascularization of decellularized scaffolds

项目总结 脱细胞器官作为大型可移植器官工程的支架具有巨大的前景 嫁接。要实现这一愿景，需要一种在这种支架内重建功能性血管树的方法。 这项R03先导性研究的目标是应用我们从血管微流控学到的经验教训 以胶原蛋白和纤维蛋白为基础的凝胶，用于脱细胞支架的血管形成。我们之前的研究表明 走向物理信号在促进功能性血管形成中的主导地位。令人惊讶的是，物理信号 很少被认为是脱细胞支架中血管形成的潜在促进剂，我们 相信它们可能是获得持久的、功能正常的血管网络所需的缺失成分。 拟议的工作将使用脱细胞的毛细血管和微血管的体外模型来快速 筛选血管形成情况，以先前识别的物理信号为起点。最多的 在这些筛查中确定的有希望的条件将在脱细胞的大鼠脂肪垫和体外肺上进行测试。 生理和组织学分析，重点是内皮屏障的完整性，将提供 器官水平和微尺度的血管功能测量。血管支架将被植入 在大鼠体内原位测定血管的功能。在完成时，拟议的工作 将产生原理证明的重新血运的器官尺度支架，准备接受实质细胞 移植物，用于最终产生血管化的功能器官。

PROJECT SUMMARY Decellularized organs hold tremendous promise as scaffolds for the engineering of large transplantable grafts. Achieving this vision will require a method to reconstruct functional vascular trees within such scaffolds. The objective of this pilot R03 study is to apply the lessons we have learned from vascularizing microfluidic collagen- and fibrin-based gels, towards the vascularization of decellularized scaffolds. Our prior studies point toward the dominance of physical signals in promoting functional vascularization. Surprisingly, physical signals have rarely been examined as potential promoters of vascularization in decellularized scaffolds, and we believe they may be the missing ingredient needed to obtain durable, functional vascular networks. The proposed work will use in vitro models of decellularized capillaries and microvessels to quickly screen vascularization conditions, with previously identified physical signals as a starting point. The most promising conditions identified in these screens will be tested on decellularized rat fat pads and lungs ex vivo. Physiological and histological analyses, with emphasis on integrity on the endothelial barrier, will provide organ-level and microscale measures of vascular function. Vascularized scaffolds will be implanted orthotopically in the rat to determine the functionality of the vessels in vivo. At completion, the proposed work will yield proof-of-principle revascularized organ-scale scaffolds that are ready to accept parenchymal cell grafts, for the eventual generation of vascularized functional organs.