Transplantation of autologous endothelial cells induces angiogenesis

This study examined the feasibility and efficacy of autologous endothelial cell (EC) transplantation using a fibrin matrix in the ischemic myocardium of sheep. Four weeks after placing an ameroid constrictor in the circumflex artery of 12 adult sheep, four animals (EC group) were subjected to EC transplantation. In four others (saline [SAL] group) saline with added inactivated cells was injected and four animals served as controls. Eight weeks after treatment the animals were sacrificed to assess histology and ultrastructure. Eight weeks after injection, ventricular function was markedly improved in the EC transplant group, but had deteriorated in the SAL and control groups. Myocardial blood flow was also increased in the EC group. Histology and electron microscopy revealed extensive neovascularization after EC transplantation and improved myocardial appearance. Heterotopic transplantation of EC within a fibrin matrix enhances neovascularization, increases myocardial blood flow, and improves left ventricular function.