MYOBLAST TRANSPLANTATION IN THE PORCINE MODEL - A POTENTIAL TECHNIQUEFOR MYOCARDIAL REPAIR

The use of transgenic cells transplanted in syngeneic rodents has show n modest success, but allogeneic and xenogeneic transplants have not b een uniformly successful. To assess the feasibility of xenogeneic and allogeneic myoblast transplantation, we subjected seven adult swine to transplantation of murine atrial tumor cells (xenogeneic), neonatal p orcine myocytes (allogeneic), and human fetal cardiomyocytes into the left ventricular wall, After general anesthesia, isolated cells were i njected along the anterior and posterior walls of the porcine left ven tricle, All the animals were immunosuppressed and observed for 1 month after injection, at which time they were killed and analyzed. This re port will present results primarily concerned with the success of huma n cell transfers. In all injected sites examined, the transplanted cel ls thrived within the host myocardium,vith no significant rejection, T ransplant cells formed close associations with host myocytes that rese mbled nascent intercalated disks on electron microscopy, These cells a lso contained myofibrils and other cell architecture resembling the tr ansplanted cell lines. Additionally, these cells appeared to produce a n angiogenic influence resulting in the proliferation of the surroundi ng microvasculature. We believe that these findings indicate successfu l xenogeneic and allogeneic myoblast cell transplantation in a large a nimal model, These experiments set the stage for future studies to ass ess the ability of these cells to form a syncytium, contract, and pote ntially repair failed myocardium.