Engineered Cardiac Tissue with Biomimetic Architecture and Vasculature

项目摘要 缺血性心脏病约占所有心血管相关死亡和折磨的42.5%。 72万人/年。尽管目前的医疗手段已经大大减少了心脏病发作- 相关的死亡率，缺血后心肌组织经历病理性重塑和瘢痕形成， 使患者发生心功能障碍和心力衰竭。由于内源性心脏再生有限， 以干细胞和再生医学为基础的心脏修复方法代表了有前途的解决方案 恢复正常的心脏功能对心血管组织工程的兴趣增加， 开发能够在3D组织样结构内维持心脏细胞功能的新型生物材料， 环境中，虽然已经开发了详细的协议，以从无数的心肌细胞中获得成熟的心肌细胞。 干细胞来源;然而，产生重现细胞来源的构建体的基本能力， 天然心脏的密度和组成、厚度和螺旋状结构限制了对心脏的治疗。 组织工程构建物的适用性。利用可光降解的聚合物基水凝胶， 使hES衍生的心肌细胞和内皮细胞的空间限定的共培养成为可能，我们建议 生成显示仿生螺旋组织结构的血管密集的3D心脏构建体。到 支持厚心肌组织的培养，增强氧气和营养物质、血管的质量运输 将被复制到含有成熟心肌细胞的细胞负载水凝胶中， 具有与天然心脏相似的尺寸、形状和结构的脉管系统。通道将内皮化 并使用仿生脉动流灌注新鲜培养基，以促进内皮-心肌细胞 互动我们的目标是证明，通过控制仿生中的微米级通道结构， 螺旋排列与近天然心脏毛细血管密度，旁分泌信号，ECM沉积，和直接 通过内皮细胞与心肌细胞的接触，可以引导心肌细胞定向，增强心肌细胞的结构， 收缩性，并重现天然扭转组织收缩。正如拟议的研究将代表 第一个成功的策略，以产生灌注血管网络与3D功能的单微米 规模，我们预计开发的方法将在工程中获得广泛的适用性 心脏组织外的血管化结构。

PROJECT SUMMARY Ischemic heart disease accounts for approximately 42.5% of all cardiovascular-related deaths and afflicts 720,000 individuals/year. While current medical treatments have significantly decreased heart attack- associated mortality, post-ischemic myocardial tissue undergoes pathologic remodeling and scarring, subjecting patients to cardiac dysfunction and heart failure. As endogenous cardiac regeneration is limited, stem cell and regenerative medicine-based approaches to cardiac repair represent promising solutions towards regaining normal heart function. Bolstering interest in cardiovascular tissue engineering has given rise to the development of novel biomaterials capable of maintaining cardiac cell function within a 3D tissue-like environment, while detailed protocols have been developed to derive mature cardiomyocytes from a myriad of stem cell sources; however, the essential ability to generate a construct that recapitulates the cellular density and composition, thickness, and helicoid structure of the native heart has limited the therapeutic applicability of tissue engineered constructs thus far. Utilizing photodegradable polymer-based hydrogels that enable a spatially-defined co-culture of hES-derived cardiomyocytes and endothelial cells, we propose to generate a densely-vascularized 3D cardiac construct exhibiting biomimetic helical tissue architecture. To support the culture of a thick myocardial tissue and enhance mass transport of oxygen and nutrients, vessels will be photopatterned into cell-laden hydrogels containing mature cardiomyocytes to generate perfusable vasculature with similar size, shape, and structure to that of the native heart. Channels will be endothelialized and perfused with fresh media using biomimetic pulsatile flow to encourage endothelial-cardiomyocyte cell interaction. We aim to demonstrate that by controlling micron-scale channel architecture in a biomimetic helical arrangement with near-native heart capillary density, paracrine signaling, ECM deposition, and direct contact of endothelial cells and cardiomyocytes, we can direct cardiomyocyte orientation, enhance construct contractility, and recapitulate the native torsional tissue contraction. As the proposed research will represent the first successful strategy to generate perfusable vasculature networks with 3D features on the single-micron scale, we expect that the developed methodologies will find wide applicability in the engineering of vascularized constructs beyond cardiac tissue.