Stem Cells FAQ
Your Stem Cell Questions Answered
Q: Why all the excitement about stem cells?
A: A relatively small number of stem cells taken from the body can be grown in the laboratory until they have created millions and millions of new stem cells. This makes it possible for researchers to explore cell-based therapies.
Cell-based therapies, collectively known as regenerative medicine, hold the promise of repairing or even replacing damaged or diseased organs.
Depending on which tissues they come from, stem cells have very different properties. Those from umbilical cord blood are quite different from those from fat, for example.
Q: Are there current stem cell treatments?
A: Yes. Stem cells from bone marrow have long been used to treat certain types of leukemia.
The bone marrow is a rich source of blood stem cells. These cells replace the white blood cells crucial to the immune system.
When used for leukemia, the goal is to to wipe out all of a person's white blood cells with radiation and/or chemotherapy -- and then to replace them with a bone marrow transplant from a matched donor. Stem cells from the donor marrow replace the diseased blood cells with healthy blood cells.
A stem cell product designed to avoid the need for a matched donor recently received limited approval in Canada. The product, Prochymal, appears to rescue bone marrow transplant patients who are rejecting their transplant.
In the U.S., the FDA has approved a product called Hemacord, which contains blood stem cells derived from cord blood. The product is approved for patients with diseases that affect their ability to make new blood cells, such as certain blood cancers and immune disorders.
Q: Are stem cell treatments safe?
A: That remains to be seen. Potential dangers include:
- As stem cells renew themselves and can become different kinds of cells, they might become cancer cells and form tumors.
- Stem cells grown in the laboratory, or adult cells reprogrammed to be stem cells, might have genetic damage.
There is also risk in some of the procedures used to get stem cells out of the body (such as from liposuction or spinal tap) or to deliver stem cells to the body (such as implanting them in the heart, brain, spinal cord, or other organs). That's not so much about the stem cells, but because of the procedures themselves.