Science often opens areas of investigation that rouse intense public debate. Such is the case with the rapidly advancing field of stem cell research.
In Missouri, debate over the use of embryonic stem cells for research &emdash; and ultimately for treatment of disease &emdash; has risen to new heights. State legislators have introduced bills in both the Missouri House and Senate to ban a technique known as somatic cell nuclear transfer (SCNT), criminalizing certain kinds of research into medical uses of embryonic stem cells in Missouri.
SB160 was recently approved by the Senate Judiciary Committee and will go to the full Senate for vote.
Missouri research institutions, including Washington University, have come out in strong opposition to the legislation, joining with other organizations to form the Missouri Coalition for Lifesaving Cures.
More than 60 leading state and national patient advocacy, business, medical, academic, research and civic organizations are members of the coalition.
SCNT creates stem cells by inserting the nucleus containing genetic material from one of a patient’s cells into an egg cell that has had its nucleus removed.
The resulting cell can be coaxed into producing embryonic stem cells that are genetically identical to the cells of the nucleus.
These stem cells are in an immature state and are able to become virtually any type of cell in the body &emdash; unlike adult stem cells found in bone marrow, intestine, nervous system and skin, which appear to be capable of transformation into only a limited number of cell types.
Physicians hold hope that stem cells created by SCNT can be used to replace malfunctioning cells in the body &emdash; for example, replacing nerve cells damaged by spinal cord injury, or cardiac cells affected by congenital heart disease or heart attacks.
Other anticipated applications include the production of pancreatic islet cells to treat diabetes and various types of nerve cells to treat Parkinson’s and Alzhei-mer’s diseases. Stem cells grown from a patient’s cells can also be used to test the effect of drugs or to assess the genetic composition of a cancerous tumor.
SCNT creates stem cells with a distinct advantage over those derived from in vitro fertilization or from older stem cell lines maintained in culture and approved by the federal government.
The stem cells created by SCNT can be individualized for each patient’s case. They would be genetically and immunologically compatible with the patient and could be used without risk of immune rejection.
Some Missouri legislators object to SCNT because of a belief that, like the union of sperm and egg during reproduction, SCNT creates an embryo.
“On the contrary, SCNT is fundamentally different from sexual reproduction,” said Steven L. Teitelbaum, M.D., the Wilma and Roswell Messing Professor of Pathology and Immunology.
“The cells produced by SCNT are genetically derived from a single person, are grown in the laboratory and will never be implanted in a uterus. SCNT cannot at this time and never should be used for human cloning &emdash; which all reasonable people are opposed to.”
Many physicians believe stem cells allow for superior treatment options over previous therapeutic methods.
As an example, one could look to the potential application of SCNT for treatment of type 1 or juvenile diabetes. Stem cells could possibly be used to replace the insulin-producing cells missing in these patients.
In non-diabetics, pancreatic islet cells respond instantly and accurately to sugar levels, releasing insulin in the right proportions to move sugar out of the bloodstream.
But people with type 1 diabetes lack functional islet cells. They need to monitor their own blood sugar levels several times a day and inject insulin to compensate for high sugar levels.
Because of the difficulty of balancing their energy intake and output, diabetics often have high and continually fluctuating blood sugar levels, which is physically harmful and can lead to retinal, kidney, heart and nerve problems.
Some success in treating diabetes has been seen with islet-cell transplants, but for the rest of their lives transplant patients must take anti-rejection drugs, which can have side effects such as anemia and kidney disease and can increase the risk of cancer and serious infection.
On the other hand, using stem cells matching the patient’s cells to replace defective pancreatic islet cells would cure the diabetes without the risk of transplant rejection. Experiments with mice have shown initial success with this approach.
Alan Permutt, M.D., professor of medicine and of cell biology and physiology and director of the Diabetes Research and Training Center, has been diabetic since he was 16. He personally knows the effect the disease has on daily life and long-term health and is enthusiastic about the potential of stem cell therapy.
“Diabetes tends to run in families,” Permutt said. “I am hopeful that before my grandson gets out of his childhood, we will have found a cure for diabetes using stem cells.”
The passage of the bill would have far-reaching negative effects on the University and the state of Missouri, according to Chancellor Emeritus William H. Danforth.
“Criminalization of SCNT would affect science, patient care and economic development,” Danforth said. “All scientists wanting to do research with SCNT would avoid this medical center and this state.
“Furthermore, the general atmosphere would make it harder to recruit and hold scientific faculty involved in related areas. Patients would be forced to travel to other states to seek appropriate, up-to-date treatment.
“In addition, Missouri would find it harder to attract startup companies in the biomedical field, which will affect the job market and future commercial development.”
Organizations and citizens who support SCNT research and oppose the effort to ban SCNT in Missouri may become members of the Missouri Coalition for Life-saving Cures. Membership is free and available through the group’s Web site, missouricures.com, or by calling (800) 829-4133.
