Abstract 12495: Fibrin-Thrombin Patch for Endothelial Cell Differentiation and Cardiac-Tissue Patch Manufacturing Using Human Induced-Pluripotent Stem Cells

Aim: To explore the feasibility using fibrin-thrombin patch for endothelial cell differentiation and cardiac scaffold manufacturing using cardiac cells derived from human induced-pluripotent stem cells (hiPSCs). Method and Result: hiPSCs were dissociated into single cells and seeded into three-dimensional (3D) fibrin-thrombin patches and undergo a two-stage differentiation protocol. With this protocol, up to 45% of the differentiated hiPSCs assumed an EC phenotype, and after purification, greater than 95% of the cells displayed the EC phenotype (based on CD31 expression). The hiPSC-ECs continued to display EC characteristics for 4 weeks in vitro. Gene and protein expression levels of CD31, CD144 and von Willebrand factor-8 (vWF-8) were significantly up-regulated in differentiated hiPSC-ECs. hiPSC-ECs also have biological function to up-take Dil-conjugated acetylated LDL (Dil-ac-LDL) and form tubular structures on Matrigel. A human cardiac-tissue patch (hiCP) was developed by seeding the hiPSC-ECs with hiPSC-derived cardiomyocytes (hiPSC-CMs) and smooth muscle cells (hiPSC-SMCs) into a 3D fibrin scaffold. The hiCP began to contract 3 days after synthesis, 4 days earlier than patches that were created identically but without hiPSC-ECs, and continued to beat regularly (100-120 beats/min) for at least 4 weeks in vitro. Conclusion: These data demonstrate that this new 3D differentiation protocol can efficiently generate stable ECs from hiPSCs and, furthermore, that the differentiated hiPSC-ECs can be combined with hiPSC-CMs and -SMCs to construct an hiCP with improved contractile activity. Our observations also suggest that interactions between the cardiac endothelium and myocytes may contribute to the optimized beating of hiCPs.