Decellularized cardiac extracellular matrix scaffolds with preserved composition and architecture can be used in tissue engineering to reproduce the complex cardiac extracellular matrix. However, evaluating the extent of cardiomyocyte repopulation of decellularized cardiac extracellular matrix scaffolds after recellularization attempts is challenging. Here, we describe a unique combination of biochemical, biomechanical, histological, and physiological parameters for quantifying recellularization efficiency of tissue-engineered cardiac patches compared with native cardiac tissue. Human embryonic stem cell-derived cardiomyocytes were seeded into rat heart atrial and ventricular decellularized cardiac extracellular matrix patches. Confocal and atomic force microscopy showed cell integration within the extracellular matrix basement membrane that was accompanied by restoration of native cardiac tissue passive mechanical properties. Multi-electrode array and immunostaining (connexin 43) were used to determine synchronous field potentials with electrical coupling. Myoglobin content (~60%) and sarcomere length measurement (>45% vs 2D culture) were used to evaluate cardiomyocyte maturation of integrated cells. The combination of these techniques allowed us to demonstrate that as cellularization efficiency improves, cardiomyocytes mature and synchronize electrical activity, and tissue mechanical/biochemical properties improve toward those of native tissue.

具有保留的组成和结构的去细胞心脏细胞外基质支架可用于组织工程中，以复制复杂的心脏细胞外基质。然而，在重新细胞化尝试之后评估脱细胞的心脏细胞外基质支架的心肌细胞重新分布的程度具有挑战性。在这里，我们描述了生化，生物力学，组织学和生理学参数的独特组合，用于量化与天然心脏组织相比组织工程化的心脏补丁的再细胞化效率。将人胚胎干细胞衍生的心肌细胞播种到大鼠心脏心房和心室脱细胞的心脏细胞外基质斑块中。共聚焦和原子力显微镜显示细胞整合在细胞外基质基底膜内，伴随着天然心脏组织被动机械性能的恢复。使用多电极阵列和免疫染色（连接蛋白43）通过电耦合确定同步场电势。肌红蛋白含量（〜60％）和肌节长度测量（> 2D培养> 45％）用于评估整合细胞的心肌细胞成熟度。这些技术的结合使我们证明，随着细胞化效率的提高，心肌细胞成熟并同步电活动，并且组织机械/生化特性朝着天然组织的方向提高。使用多电极阵列和免疫染色（连接蛋白43）通过电耦合确定同步场电势。肌红蛋白含量（〜60％）和肌节长度测量（> 2D培养> 45％）用于评估整合细胞的心肌细胞成熟度。这些技术的结合使我们证明，随着细胞化效率的提高，心肌细胞成熟并同步电活动，并且组织机械/生化特性朝着天然组织的方向提高。使用多电极阵列和免疫染色（连接蛋白43）通过电耦合确定同步场电势。肌红蛋白含量（〜60％）和肌节长度测量（> 2D培养> 45％）用于评估整合细胞的心肌细胞成熟度。这些技术的结合使我们证明，随着细胞化效率的提高，心肌细胞成熟并同步电活动，并且组织机械/生化特性朝着天然组织的方向提高。