Engineering Vascularized Cardiac Muscle

我们目前无法使厚细胞团血管化和灌注，这阻碍了工程化许多细胞的努力。 包括最重要的心肌在内的各种功能组织。作为心肌修复的移植物， 工程化的心脏结构必须厚而紧凑，含有生理密度的分化的 细胞，并且响应于电刺激而同步收缩。此外，移植物必须具有 与宿主脉管系统整合以维持移植物的活力和功能的能力 细胞我们建议通过整合和推进我们的 心脏组织工程（MIT）和血管组织工程（杜克）领域的持续努力。我们 假设培养心肌细胞和内皮细胞！细胞在专门的支架上（高度 多孔的、可生物降解的、弹性的、具有通道阵列的）在具有介质灌注的生物反应器中， 电刺激将促进同步收缩的工程化肌肉的功能组装。我们 进一步假设体外血管化将增强移植物存活、整合和 在体内发挥作用。为了验证这些假设，这些假设来自我们以前的两条线。 本研究的主要目的是：（1）高密度培养心肌细胞， 在具有介质灌注和电刺激的通道支架上的肌细胞，（2）组织 血管化网络的工程化，和（3）血管化网络的组织工程化和功能表征。 血管化的心肌灌流和电刺激对脑缺血再灌注损伤的影响 将在体外研究内皮细胞和肌细胞组装成同步收缩心肌 和体内（植入到成年大鼠梗塞模型的左心室）。组织结构和功能 将在不同的层次尺度（分子，结构，功能）和获得的特征 实验和建模数据将用于定制培养和工程的条件和持续时间 可植入的移植物因此，目前的建议是生成血管化心脏的蓝图。 适合植入受损心肌的肌肉。

Our current inability to vascularize and perfuse thick cell masses has hindered efforts to engineer many types of functional tissues including, most critically, cardiac muscle. To serve as a graft for myocardial repair, an engineered cardiac construct must be thick and compact, contain physiologic density of differentiated cells, and contract synchronously in response to electrical stimulation. In addition, the graft must have a capability to integrate with the host vasculature in order to maintain the viability and function of transplanted cells. We propose to engineer functional vascularized myocardium by integrating and advancing our ongoing efforts in the areas of cardiac tissue engineering (MIT) and vascular tissue engineering (Duke). We hypothesize that the cultivation of cardiac myocytes and endothelia! cells on specialized scaffolds (highly porous, biodegradable, elastic, with an array of channels) in a bioreactor with medium perfusion and electrical stimulation will promote functional assembly of synchronously contractile engineered muscle. We further hypothesize that vascularization in vitro will enhance the graft capacity for survival, integration and function in vivo. In order to test these hypotheses, which have been derived from two lines of our previous investigations, we propose studies with the following Specific Aims: (1) High density culture of cardiac myocytes on channeled scaffolds with medium perfusion and electrical stimulation, (2) Tissue engineering of a vascularized network, and(3) Tissue engineering and functional characterization of a vascularized cardiac muscle. The effects of perfusion and electrical stimulation on the progressionof endothelial cell and myocyte assembly into a synchronously contractile myocardium will be studied in vitro and in vivo (implantation onto a left ventricle in an adult rat model of infarction). Tissue structure and function will be characterized at various hierarchical scales (molecular, structural, functional) and the obtained experimental and modeling data will be used to tailor the conditions and duration of cultivation and engineer implantable grafts. As such, the current proposal is a blueprint for the generation of vascularized cardiac muscle suitable for implantation into injured myocardium.