An injectable alginate/fibrin hydrogel encapsulated with cardiomyocytes and VEGF for myocardial infarction treatment

Myocardial infarction (MI) is one of the typical cardiovascular diseases, which persist as the leading cause of death globally. Due to the poor regenerative capability of endogenous cardiomyocytes (CMs), the transplantation of exogenous CMs becomes a promising option for MI treatment. However, the low retention and survival of transplanted cells still limit the clinical translation of cell therapy. Herein, an alginate/fibrin-based injectable hydrogel was prepared for the delivery of neonatal CMs and an angiogenesis agent vascular endothelial growth factor (VEGF) locally to the infarcted area of the heart. This hydrogel combined the specific advantages of alginate and fibrin with proper mechanical properties and cell affinity, showing good biocompatibility to support the retention and integration of the transplanted CMs to the host myocardium. Moreover, the delivered VEGF was favorable for the blood recovery to mitigate the ischemic microenvironment of the infarcted area and thus improved the survival of the transplanted CMs. Intramyocardial injection of this hydrogel to the infarcted area of the heart promoted angiogenesis, inhibited fibrosis, and improved cardiac function, exhibiting great potential for MI treatment.