Cardiac Cell Transplantation: Protocols and Applications

Cellular transplantation into the heart is an emerging field with numerous applications for designing new therapeutic strategies for treating various types of heart disease. The two primary applications of cellular transplantation are to generate new functional myocardium and to deliver therapeutic agents such as growth factors into diseased hearts. Cardiac cellular transplantation experiments have been performed using different cell types, including cardiomyocyte cell lines (1 ), primary cardiomyocytes (2 ,3 ), skeletal myocytes (4 –6 ), and fibroblasts (7 ). In performing cardiac cellular transplantation experiments, various animal models have been used to assess the efficacy of autologous (8 ), syngeneic (9 ), allogeneic, and xenogeneic (1 ,10 ) cellular transplants. Many investigators are currently focusing on using embryonic stem (ES) cells (10 ,11 ) and bone marrow-derived stem cells (12 ,13 ) for in vitro differentiation into cardiomyocytes for transplantation, or as direct sources for cardiac cellular transplantation. In order for cells to be useful for transplantation into injured myocardium, they must be able to survive in the recipient tissue, have limited capacity for replication, and become physically and electrically coupled to each other and the neighboring host myocardium so that they may all contract synchronously.