MICROFABRICATED 3D VASCULARIZED CARDIAC TISSUE CONSTRUCTS

描述（由申请人提供）：由心肌细胞（CM）丧失或功能障碍引起的心血管疾病是导致死亡的主要原因，影响全球数百万人。组织工程在修复受损心脏方面有很大的希望，但需要功能性组织结构的工程化。当前心血管组织工程方法的一些关键限制包括不能产生载有细胞和细胞粘附的生物材料、工程化血管化组织以及模拟心脏组织的生物复杂性和微结构。为了应对这些挑战，我们的目标是将联合收割机创新的微尺度技术和先进的生物材料（即水凝胶）相结合，以创建载有细胞的水凝胶，并开发具有受控物理和生物学特性的3D血管化心脏组织结构。我们将主要使用天然光交联水凝胶（明胶甲基丙烯酸酯，GelMA）来开发高度组织化的3D血管化网络。具体而言，我们将在图案化的水凝胶结构内共培养内皮细胞（EC）和间充质干细胞（MSC），并诱导MSC向平滑肌细胞分化，并开发具有受控几何特征和生物学特性的仿生血管系统。然后，我们将把心肌细胞包封在另一层水凝胶内，并将其与预先开发的血管化网络结合联合收割机，以生成具有可变构型和受控复杂性的心脏组织构建体。通过将CM与对齐的EC和MSC进行三重培养，我们将广泛研究组织构建体的生物学特性。此外，本发明还提供了一种方法， 我们将在循环拉伸条件下测试所开发的血管化构造的功能。最后，我们将评估工程化心脏组织构建体在体内的功能特性。该项目的成果对于心血管组织再生将是重要的，其中基质材料的性质和构型在维持心脏和血管组织的天然结构架构方面起着重要作用。此外，开发的构建体可以用作药物细胞毒性研究的综合平台。

DESCRIPTION (provided by applicant): Cardiovascular diseases caused by the loss or dysfunction of cardiomyocytes (CMs) are the leading cause of death and affect millions of people worldwide. Tissue engineering holds great promise for the repair of injured hearts but requires the engineering of functional tissue constructs. Some of the key limitations of current cardiovascular tissue engineering approaches include the inability to generate cell-laden and cell- adhesive biomaterials, engineer vascularized tissues, and mimic the biological complexity and microarchitecture of cardiac tissues. To address these challenges, we aim to combine innovative microscale technology and advanced biomaterials (i.e. hydrogels) to create cell-laden hydrogels and develop 3D vascularized cardiac tissue constructs with controlled physical and biological properties. We will primarily use natural-based photocrosslinkable hydrogels (gelatin methacrylate, GelMA) to develop highly organized 3D vascularized networks. Specifically, we will co-culture endothelial cells (ECs) and mesenchymal stem cells (MSCs) within the patterned hydrogel construct and induce MSCs differentiation toward smooth muscle cells and develop biomimetic vasculature with controlled geometrical features and biological characteristics. Then, we will encapsulate cardiomyocytes within another layer of hydrogel and combine it with the pre- developed vascularized networks to generate cardiac tissue constructs with variable configurations and controlled complexities. Through the triple-culture of CMs with aligned ECs and MSCs, we will extensively study the biological properties of the tissue construct. In addition, we will test the functionality of the developed vascularized construct under cyclically stretched conditions. Finally, we will assess the functional properties of the engineered cardiac tissue construct in vivo. Achievements in this project will be important for cardiovascular tissue regeneration where the matrix material properties and configuration play an important role in maintaining native structural architecture of cardiac and vascular tissues. In addition, the developed constructs can be used as an integrative platform for drug cytotoxicity studies.