- Fat-Fighting Foods Slideshow
- Take the Human Body Quiz
- Causes of Fatigue Slideshow Pictures
- Patient Comments: Stem Cells - Experience
- Stem cell facts
- What are stem cells?
- Why are stem cells important?
- Embryonic stem cells
- Fetal stem cells
- Adult stem cells
- Peripheral blood stem cells
- Umbilical cord stem cells
- Induced pluripotent stem cells
- Why is there controversy surrounding the use of stem cells?
- What are some stem cell therapies that are currently available?
- What are experimental treatments using stem cells and possible future directions for stem cell therapy?
Why is there controversy surrounding the use of stem cells?
Embryonic stem cells and embryonic stem cell lines have received much public attention concerning the ethics of their use or non-use. Clearly, there is hope that a large number of treatment advances could occur as a result of growing and differentiating these embryonic stem cells in the laboratory. It is equally clear that each embryonic stem cell line has been derived from a human embryo created through in-vitro fertilization (IVF) or through cloning technologies, with all the attendant ethical, religious, and philosophical problems, depending upon one's perspective.
What are some stem cell therapies that are currently available?
Routine use of stem cells in therapy has been limited to blood-forming stem cells (hematopoietic stem cells) derived from bone marrow, peripheral blood, or umbilical cord blood. Bone marrow transplantation is the most familiar form of stem cell therapy and the only instance of stem cell therapy in common use. It is used to treat cancers of the blood cells (leukemias) and other disorders of the blood and bone marrow.
In bone marrow transplantation, the patient's existing white blood cells and bone marrow are destroyed using chemotherapy and radiation therapy. Then, a sample of bone marrow (containing stem cells) from a healthy, immunologically matched donor is injected into the patient. The transplanted stem cells populate the recipient's bone marrow and begin producing new, healthy blood cells.
Umbilical cord blood stem cells and peripheral blood stem cells can also be used instead of bone marrow samples to repopulate the bone marrow in the process of bone marrow transplantation.
In 2009, the California-based company Geron received clearance from the U. S. Food and Drug Administration (FDA) to begin the first human clinical trial of cells derived from human embryonic stem cells in the treatment of patients with acute spinal cord injury.