WEDNESDAY, July 28, 2004 (HealthDayNews) -- Stem cell research stayed in the public spotlight Tuesday night as Ron Reagan, son of the late 40th President, took his plea to loosen White House restrictions on such science to the Democratic National Convention in Boston.
Most experts sensed irony in the younger Reagan's address, which he hopes will help prevent others from suffering the ravages of Alzheimer's disease, the degenerative neurological condition that killed his father. They say that Alzheimer's is not going to be the main -- or even the first -- beneficiary of this cutting-edge research.
Breakthroughs are more likely to happen with other neurological disorders such as Parkinson's disease, diabetes, head and spinal cord injuries, and damage from strokes and heart attacks, said Paul R. Sanberg, director of the Center for Aging and Brain Repair at the University of South Florida College of Medicine.
Stem cells have been the subject of both scientific and political scrutiny.
These types of cells are blank slates that can turn into any type of cell and, as a result, have enormous scientific potential. It is hoped that one day they may be a source of cells to replace damaged or lost ones in humans. There are several sources of stem cells, namely human embryos, certain adult tissues (such as the bone marrow), and the umbilical cords of newborn babies.
Embryonic stem cells are the most controversial type. Their use in federally funded research is limited to those derived before Aug. 9, 2001, a Bush administration policy. The National Institutes of Health has about 15 such lines available, but by most accounts, they are difficult to obtain and ill-equipped for rigorous research.
In March, scientists announced the creation of 17 new human embryonic stem cell lines that would be available to other researchers and which would not be subject to current restrictions. The cells are being grown at the new Harvard Stem Cell Institute.
While embryonic stem cells seem to hold the most medical potential because they are "pluripotent" (able to develop into any kind of cell), advances have also been made with adult stem cells, considered to be "multipotent" (able to develop into many but not all cells).
Earlier this month, British researchers used adult skin cells to generate nerve precursor cells, which may have implications for Parkinson's and other diseases.
Similarly, German researchers recently succeeded in using a person's own bone marrow stem cells to help repair the heart after a heart attack.
More hope is resting with embryonic stem cells.
"Thus far, the most innovative work from the human standpoint is being done with embryonic stem cells," said Dr. Philip E. Stieg, a professor and chairman of neurological surgery at Weill Medical College of Cornell University and neurosurgeon-in-chief at New York Presbyterian Hospital.
Embryonic cells have been coaxed into becoming different components of the central nervous system, Stieg added, and scientists may be close to a clinical trial with spinal cord injury patients. And a study just reported this week detailed the first successful use of fetal stem cells to grow neurons in stroke-damaged brain areas of rats.
Researchers have also had success instructing embryonic stem cells in mice to become insulin-secreting cells, a feat that holds possibilities for curing type 1 diabetes, said Dr. Bob Goldstein, chief scientific officer of the Juvenile Diabetes Research Foundation.
Stem cells may also have surprise applications in gene therapy. "The next hope will be can we modify [stem cells'] gene composition and also direct them into becoming specific cell types," Stieg said.
"Everyone is moving forward, but nothing is really in clinic at this point," Sanberg said. "Adult stem cells and cord blood cells are probably closer to clinic. In fact, they are in clinic in cancer patients."
"I think most scientists agree that we need to continue research in both areas [embryonic and adult]," he continued.
One other point is that stem cells may not need to survive in the body to be therapeutic. "It's not so much cell replacement, it's these new cells are inducing the body to repair itself," Sanberg explained.
Another question is where this research will take place. In February, South Korean researchers announced they had managed to extract stem cells from cloned human embryos.
Restrictions on the use of embryonic stem cells in the United States, Stieg said, "will drive research to other environments," among them Sweden, Israel, Australia, England and Canada.
"If America wants to lead the scientific community, it's not going to do it from the point of view of saying, 'We won't do it,'" Stieg said. "It's going to go on without us."
More information
Visit the International Society for Stem Cell Research for more on stem cells.
