Background-Successful autologous skeletal myoblast transplantation into infarcted myocardium in a variety of animal models has demonstrated improvement in cardiac function. We evaluated the safety and feasibility of transplanting autologous myoblasts into infarcted myocardium of patients undergoing concurrent coronary artery bypass grafting (CABG) or left ventricular assist device (LVAD) implantation. In addition, we sought to gain preliminary information on graft survival and any associated changes in cardiac function. Methods and Results-Thirty patients with a history of ischemic cardiomyopathy participated in a phase I, nonrandomized, multicenter pilot study of autologous skeletal myoblast transplantation concurrent with CABG or LVAD implantation. Twenty-four patients with a history of previous myocardial infarction and a left ventricular ejection fraction Ͻ40% were enrolled in the CABG arm. In a second arm, 6 patients underwent LVAD implantation as a bridge to heart transplantation, and patients donated their explanted native hearts for testing at the time of heart transplantation. Myoblasts were successfully transplanted in all patients without any acute injection-related complications or significant long-term, unexpected adverse events. Follow-up positron emission tomography scans showed new areas of glucose uptake within the infarct scar in CABG patients. Echocardiography measured an average change in left ventricular ejection fraction from 28% to 35% at 1 year and of 36% at 2 years. Histological evaluation in 4 of 6 patients who underwent heart transplantation documented survival and engraftment of the skeletal myoblasts within the infarcted myocardium. Conclusions-These results demonstrate the survival, feasibility, and safety of autologous myoblast transplantation and suggest that this modality offers a potential therapeutic treatment for end-stage heart disease. (Circulation. 2005;112: 1748-1755.)

The movement disorder in Parkinson's disease results from the selective degeneration of a small group of dopaminergic neurons in the substantia nigra pars compacta region of the brain. A number of exploratory studies using human fetal tissue allografts have suggested that transplantation of dopaminergic neurons may become an effective treatment for patients with Parkinson's disease and the difficulty in obtaining human fetal tissue has generated interest in finding corresponding non-human donor cells. Here we report a post-mortem histological analysis of fetal pig neural cells that were placed unilaterally into the caudate-putamen brain region of a patient suffering from Parkinson's disease. Long-term (over seven months) graft survival was found and the presence of pig dopaminergic neurons and other pig neural and glial cells is documented. Pig neurons extended axons from the graft sites into the host brain. Furthermore, other graft derived cells were observed several millimeters from the implantation sites. Markers for human microglia and T-cells showed only low reactivity in direct proximity to the grafts. This is the first documentation of neural xenograft survival in the human brain and of appropriate growth of non-human dopaminergic neurons for a potential therapeutic response in Parkinson's disease.