Intramyocardial Transplantation of Human iPS Cell–Derived Cardiac Spheroids Improves Cardiac Function in Heart Failure Animals

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Highlights • hiPSCs are differentiated into CMs with large-scale 2-dimensional culture system, and refined by metabolic purification. • hiPSC-derived CMs are developed into CSs in special microwell plates. • Intramyocardial transplantation of CSs and GH improves cardiac function in small and large animal models. • Engraftment of CMs and angiogenesis are mechanisms for improvement of cardiac function. • Intramyocardial transplantation of CSs with a transplant injection device is a safe, effective, and feasible strategy for the treatment of HF.
Summary The severe shortage of donor hearts hampered the cardiac transplantation to patients with advanced heart failure. Therefore, cardiac regenerative therapies are eagerly awaited as a substitution. Human induced pluripotent stem cells (hiPSCs) are realistic cell source for regenerative cardiomyocytes. The hiPSC-derived cardiomyocytes are highly expected to help the recovery of heart. Avoidance of teratoma formation and large-scale culture of cardiomyocytes are definitely necessary for clinical setting. The combination of pure cardiac spheroids and gelatin hydrogel succeeded to recover reduced ejection fraction. The feasible transplantation strategy including transplantation device for regenerative cardiomyocytes are established in this study.