Stem Cell Research Q & A
Noted Cancer Biologist, Mary J.C. Hendrix, PhD, president and scientific director of the Children’s Memorial Research Center, provides insight on the topic of stem cell research.
1. What are embryonic stem cells?
They are undifferentiated cells that can both renew themselves and give rise to specialized cells. This means that they can divide indefinitely to produce as much tissue as needed for therapy, and they can be coaxed to develop into virtually any type of body cell.
2. Where do embryonic stem cells come from?
With a donor’s consent, they can be transplanted from frozen embryos (at the 150-200 cell stage) at In Vitro fertility clinics because they are in excess of a couple’s clinical need.
Stem cells can also be derived through somatic cell nuclear transfer. This involves removing the nucleus of a donor’s unfertilized egg and replacing it with the nucleus of an adult cell, such as a skin, heart or nerve cell. No sperm is used in the procedure, and thus, there is no fertilization. The cell, with its new nucleus, is placed in a lab dish and stimulated to begin dividing. After a few days, it develops into a cellular ball from which researchers can transplant embryonic stem cells. These stem cells are genetically identical to the individual in whom they will be transplanted, which eliminates the danger of immune rejection and dramatically increases the potential for successful therapy.
3. How might stem cells help cure diseases?
Because embryonic stem cells have the potential to give rise to many different types of tissues, they could provide cures through cell replacement therapies for diseases and disorders. This could help treat or cure diseases such as arthritis, diabetes, cancer, heart disease, Alzheimer's, cystic fibrosis, multiple sclerosis, sickle cell disease, Parkinson's, HIV/AIDS, osteoporosis, ALS, autism, severe burns and spinal cord injury.
4. What’s the difference between adult and embryonic stem cells?
Both adult and embryonic stem cells hold promise for curing diseases, but they are not interchangeable. Adult stem cells are more difficult to identify and isolate in the body; they are more restricted in their ability to differentiate into the wide range of cell types present in the human body, and their ability to replicate is not as robust. Thus, it is more difficult to generate the amount of tissue required for many types of transplantation. Embryonic stem cells can divide indefinitely and differentiate into all cell types in the body.
5. Does stem cell research involve reproductive cloning?
No. Cloning a human being requires transfer to a uterus and further development and gestation. A blastocyst cannot develop on its own into a human being unless successfully implanted into a woman’s uterus.
6. Is there any evidence that embryonic stem cells will produce cures?
Yes, and the evidence is growing as more research is encouraged in other countries. For specific evidence related to diabetes, neurological disease and cancer, please see my 2005 testimony before the Illinois House Executive Committee.
7. Why is good public policy for stem cell research important?
Public policy and/or public funding can ensure that stem cell research is done ethically by making it subject to public oversight and establishing controls. For example, there is currently no federal or state law that bans human reproductive cloning.
Researchers have discovered that all of the stem cell lines derived before August 9, 2001 on which the National Institutes of Health may fund research are contaminated with animal molecules from the culture medium used to sustain them.
Therefore, several states are considering legislation or funding mechanisms to support this research and to attract and retain stem cell researchers. States that are successful in passing this kind of legislation are likely to be the first ones to develop breakthroughs and treatments, and the first ones to offer these treatments to their citizens through clinical trials.