Stem cells are very special cells for they can be differentiated into any type of cell, from blood cells, muscle cells, heart cells, or even brain cells. Stem cells deserve all the media attention they’ve been getting. Research on stem cells is helping us understand how our bodies formed from single cells and that may possibly change the way we treat common diseases, such as diabetes, Alzheimer’s, and heart disease. Every cell in the body has a specific job: heart cells beat to pump blood; muscle cells contract so that you can move; and stem cells make new cells. Stem cells aren’t just interesting to scientists—over the past few years, stem cell has become a household term. Stem cells have captured the public’s attention because they have the potential to revolutionize the way we treat debilitating diseases and injuries. That’s because new cells could be grown from stem cells to replace cells that have been damaged or destroyed. Researchers caution that it will be many years before they are able to grow new cells or organs for human transplant.

We are just learning how to grow stem cells and how to signal them to develop into specialized cells, like heart or brain cells. But some doctors aren’t waiting until they can grow new cells for patients; instead, they’re experimenting with therapies in which patients are injected with unspecialized stem cells. For example, one therapy currently undergoing clinical trials treats people whose hearts have been damaged by heart attacks. To try to restore heart function, a few doctors have injected stem cells from bone marrow into the arteries that lead to the heart in such patients. Some of these patients have reported feeling much better. However, this treatment is extremely controversial because no one knows where the stem cells go or what types of cells they may become inside the patient. Despite the controversy, a number of U.S. hospitals are testing this treatment. If it works, it will be one of the first examples of stem cells being used to treat disease. Embryonic stem cells can be grown in culture dishes. A pinkish solution provides the sugars and other compounds the cells need to grow. When people think of the possible medical benefits of stem cell research, they usually think of cells and organs being grown for transplanting into people with critical illnesses. But stem cells may have an even bigger impact by giving researchers new ways to study disease and by speeding up the development of new drugs. Embryonic stem cells have the potential to turn into almost any type of cell—including diseased cells. South Korean researchers have already created stem cells from patients with diabetes, and from others with a rare immune disease called CGH, or congenital hypogamma-globulanemia. These varieties or “lines,” of stem cells will allow researchers to look closely at the actual cellular mechanisms involved in these diseases. Recreating a specific disease in a dish using stem cells may also speed up the development of lifesaving drugs. Thousands of drugs could be quickly tested on almost unlimited supply of diseased cells that might be grown from stem cells. Such rapid screening could make useful drugs available years earlier than they might be otherwise.