Embryonic Stem Cells and the Future of Transplantation
Posted Jul 06 2009 8:06pm
Stem cell therapies promise to be one of those true scientific breakthroughs that will have an impact on health care in the future. Stem cells will bring us closer to the goal of personalized medicine, just as genomics is doing. With stem cells, projections need to be five, ten, even fifteen years out – because this is truly an emerging science. The course of a disease will change once we have the technology to insert stem cells into the human body to actually create a tissue. For example, a person with a heart attack will not go on to live the rest of his or her life with damaged heart muscle and resultant heart failure. Instead, stem cells will regenerate the heart and make it whole again. Similarly, a person with Parkinson’s disease will recover full faculties thanks to the ability of stem cells to regenerate the damaged area of the brain. The person with type I diabetes will be free of the disease because of the formation of new pancreatic islet cells. The athlete will play again because new cartilage will be created for the worn knee. This is the promise of “regenerative medicine.” It is a promise that is already being kept with adult stem cells used for treating patients with immune defects, usually children, or those with some cancers. Sometimes doctors use the patients own stem cells to give the bone marrow a “boost” after intensive chemotherapy for cancer [called autologous transplants.] Or the stem cells of a closely matched donor are used for a leukemia patient to not only restore the bone marrow after aggressive therapy but also to attack any remaining leukemia cells [known as allogeneic transplants.]. And adult stem cells are being used today in research studies of patients who have had heart attacks leaving their heart muscle weakened. The president has just created an important enablement to further research on stem cells. Yes, it is true that much can be done with adult stem cells but science so far suggests that embryonic stem cells hold promise for much more benefit. It will probably be embryonic stem cells that pave the way for replacing the islet cells of the pancreas with new insulin producing cells to cure diabetes or replace the damaged cells in the brain that are key to Parkinson’s disease. Some strongly feel that it is wrong to use cells form embryos. It is important to remember that these are fertilized eggs that were prepared for couples that could not conceive and so had eggs and sperm placed into a dish with special fluids. Experience has shown that success is better if the doctor implants a few embryos into the woman’s uterus rather than just one. But the doctor may have more than enough embryos and the extras will be discarded if the woman becomes pregnant. I look at it this way. Since the embryos will be destroyed anyway, why not use them for creating stem cells that perhaps many people with diverse diseases might benefit from. It is not dissimilar to transplanting the organs of a person who has died in a car accident rather than burying them in the grave. And there is no issue about “human cloning” – that is just not what is being done or proposed. And the embryo, made up of just a few cells, is disrupted so each cell grows independently. Now the cells can be stimulated to become heart cells, liver cells or what ever might be useful in treating a disease. It will take some years but there will certainly be major advances in how we can repair, restore or replace damaged tissues or organs.