Injectable Hydrogel Helps Bone Marrow-Derived Mononuclear Cells Restore Infarcted Myocardium

<i>Backgrounds:</i> Experimental and clinical studies have suggested that cell implantation could improve cardiac function after myocardial infarction (MI). However, this technique was limited by decreased engraftment and survival of transplanted cells within the ischemic tissue. The present study was performed to investigate whether implantation of bone marrow-derived mononuclear cells (BMMNCs) encapsulated in hydrogel could increase cell engraftment and help to restore cardiac function of MI rabbits. <i>Methods:</i> MI was induced in rabbits by coronary artery ligation. One week later, cell culture medium, Dex-PCL-HEMA/PNIPAAm hydrogel, BMMNCs in medium or BMMNCs in hydrogel were injected into the infarcted area of the left ventricle (LV). <i>Results:</i> Increased cell engraftment was observed 48 h after injection when cells were encapsulated in hydrogel; 30 days after treatment, echocardiographic studies showed that injection of BMMNCs in hydrogel preserved LV ejection fraction and attenuated LV dilatation compared with other groups. Histological analysis indicated that injection of BMMNCs in hydrogel enhanced neovascular formation and prevented scar expansion compared with the other groups. <i>Conclusion:</i> Injection of hydrogel-encapsulated BMMNCs increased cell engraftment and improved LV function; this technique may serve as an effective approach to restore infarcted myocardium.