Embryonic stem cells cultured in biodegradable scaffold repair infarcted myocardium in mice

Our previous findings demonstrated that directly injecting embryonic stem cells (ESCs) into ischemic region of the heart improved cardiac function in animals with experimental myocardial infarction (MI). Tissue engineering with stem cells may provide tissue creation and repair. This study was designed to investigate the effectiveness of grafting of ESC-seeded biodegradable patch on infarcted heart. MI in mice was induced by ligation of the left coronary artery. Mouse ESCs were seeded on polyglycolic-acid (PGA) material patches. Three days after culture, an ESC-seeded patch was transplanted on the surface of ischemic and peri-ischemic myocardium. Eight weeks after MI operation and patch transplantation, hemodynamics and cardiac function were evaluated in four (sham-operated, MI, MI + cell-free patch, and MI + ESC-patch) groups of mice. The blood pressure and left ventricular function were significantly reduced in the MI animals. Compared with MI alone and MI + cell-free patch groups, the animals received MI + ESC-seeded patches significantly improved blood pressure and ventricular function. The survival rate of the MI mice grafted with MI + ESC-seeded patches was markedly higher than that in MI alone or MI + cell-free patch animals. GFP-positive tissue was detected in infarcted area with grafting of ESC-seeded patch, which suggests the survivors of ESCs and possible myocardial regeneration. Our data demonstrate that grafting of ESC-seeded bioabsorbable patch can repair infarcted myocardium and improve cardiac function in MI mice. This novel approach of combining stem cells and biodegradable materials may provide a therapeutic modality for repairing injured heart.