Myocardial infarction can lead to death and disability with a 5-year death rate for congestive heart failure of 50%. It is estimated that cardiovascular disease is the leading cause of mortality and morbidity and is predicted to be the leading cause of death worldwide by 2020. Currently, heart transplantation is the only successful treatment for end-stage heart failure; however, the ability to provide this treatment is limited by the availability of donor hearts. Therefore, alternative therapies for both acute and chronic myocardial ischemia need to be developed.
Our results demonstrate that human embryonic stem cell (hESC)-derived hemangioblasts can create new blood vessels and improve blood flow in a rodent model of myocardial infarction. We demonstrated that adult stem cells (bone marrow CD34+ cells) can be successfully targeted to injured heart tissue, thus avoiding surgery or invasive catheter based therapies. The antibody technology can be used to target hESC-derived hemangioblasts specifically to injured heart tissue.
Further studies are needed to confirm our initial findings, determine whether the new blood vessel formation lead to an increase in heart function and safety studies. Studies are in progress to improve the efficiency and effectiveness of hESC-derived hemangioblasts to create new blood vessels. Additionally, investigations are underway to determine if immunosuppressive drugs will be necessary to increase survival of the hESC-derived hemangioblast. Our initial finding of hES-derived hemangioblasts inducing new blood vessel formation may eventually lead to the development of an unlimited and reliable cell source for renewing blood vessels and treating myocardial infarction.