Abstract 712: The Right Atrium of Patients with Various Heart Diseases Retain Progenitor Cells with Regenerative Capacity
BACKGROUND: The notion that the adult human heart contains a pool of cardiac progenitor cells (hCPC) can be translated into an attractive approach to repair damaged hearts. However, significant amount of data regarding the characterization and function of hCPC are lacking, and no efficient, reproducible method exists to isolate CPC from human hearts.
OBJECTIVE: To determine whether the hearts of patients with ischemic and non-ischemic heart disease contain cardiac progenitor cells with regenerative capacity.
METHODS AND RESULTS: We developed an efficient and reproducible method to isolate hCPCs from the myocardium of patients with ischemic and non-ischemic heart disease, heart failure and diabetes. Following patients’ consent tissue samples were donated during all kinds of open heart surgery and percutaneous RV septum biopsies. Isolated cells created typical clones, possessed self-renewal capacity and expressed stem cell markers including C-Kit, CD133, MDR1, and GATA 4. Following in-vitro manipulation, hCPC successfully differentiated into the osteogenic, adipogenic and myogenic lineages. Cell cultures from the right atrium were found to have larger amounts of C-Kit+ cells (17%) compared with the left atrium (5.7%) or septum (7.9%). Correspondingly, right atrium cells had better in-vitro differentiation capabilities. hCPC were injected into nude rat myocardium to examine myogenic differentiation. After one week, some cells still expressed stem cell markers, such as CD133 and C-Kit+, while others expressed specific human cardiac markers, such as human cardiac troponin I and human fetal cardiac α-actin with early sarcomere formation, indicating that some of the implanted human cells developed into cardiomyocytes in vivo.
CONCLUSIONS: Our preliminary findings suggest that adult human heart, especially the right atrium, retains a unique cell population with stem cell markers and multi-lineage differentiation capability. These cells, which can be isolated, expanded and stored, could be used to treat patients with heart disease.