- The Washington Times - Thursday, July 19, 2001

The biochemists, physicians and other scientists doing embryonic stem-cell experiments say the research has gone too far to stop — regardless of what politicians decree.
The work is too exciting, the potential for new therapies and cures too promising, and the opportunity to accumulate new and fundamental knowledge so assured that researchers say they will find ways to continue their efforts.
They say that once again the pace of research has made the policy debate passe, while the dust it raises keeps the public from seeing where stem-cell science really is.
Stem cells are tiny organisms that can be seen only when viewed through microscopes that magnify their size 20 to 40 times. They have the ability to divide endlessly in the nutrients, or culture, provided in the laboratory, and they can grow into specialized cells within the body.
Some of the cells have the potential to develop into cells that become one or a few of the body's parts. They are "multipotent." Others, called "pluripotent," can develop into most of the body's parts, but they can't become a fetus. Still others, called "totipotent," have unlimited capacity and can develop into any of the body's membranes and tissues.
Human pluripotent and totipotent stem cells are believed to have most potential for revolutionizing medicine and have created the most research interest. But they currently are obtained from 4-day-old embryos. There lies a relentless policy debate.
Removing the stem cells from the embryo ends its viability. So some say that removing them is tantamount to murder, and that funding such research with taxpayer money should be banned. Others — especially those in the medical communities — call "harvesting" cells from embryos a needed step in the quest to save lives.
Sen. Bill Frist, Tennessee Republican, the only physician in the Senate, sides with the medical researchers. He declared yesterday, "I conclude that embryonic and adult stem-cell research should be federally funded within a carefully regulated, fully transparent framework."
Mr. Frist's endorsement is expected to carry considerable weight. He is a close ally of President Bush, who is expected to make a decision about the federal funding of stem-cell research next week.
If Mr. Bush decides against the use of federal funds to support the research, private interests will do so, says Evan Snyder, a Harvard University biochemist. He says the scientific community generally understands the work will be supported mainly by biotech companies that envision gigantic profits from expected new therapies.
And if companies provide research money, academic scientists will gravitate to company labs where the results of their work will be corporate secrets, and research progress will slow. That's because accounts of both successful and failed company experiments will be unavailable to others: Scientists will be barred from building on each others' work as they do in the academia.
Ultimately, Mr. Snyder predicts, stem cell therapies for Alzheimer's disease, diabetes, spinal cord injuries, stroke, heart disease and the rest will be priced exorbitantly so companies can quickly recoup research costs. Only the richest patients will be able to afford the treatments, he says.
Although harvesting embryonic cells is a major issue, research has gone beyond the point where harvesting stem cells is a prime goal. As Mr. Snyder explains, "The goal is to pull out just enough cells to establish cell lines that can dwell in the lab. That will keep us from ever having to go back to the well."
Cell lines can be thought of as colonies of stem cells that live and flourish in the lab. Since the cells duplicate endlessly, a cell line can produce an abundant supply of research cells for years.
The same cannot be said of adult stem cells, says Larry Goldstein, a biochemist at the University of California at San Diego. His words echo the findings of a study the National Institutes of Health released yesterday. It reports that embryonic cells have a great advantage over adult cells for medical research.
The study and the biochemist both note, as Mr. Goldstein puts it: "We're pretty near the beginning in terms of figuring out how to harness either embryonic or adult stem cells into therapeutic intervention in humans."
It's true that doctors are using stem cells found in blood and in bone marrow with relative sophistication to treat certain cancers. Still, as Mr. Goldstein explains, almost everything scientists know about embryonic stem cells comes from thousands and thousands of experiments on mice and a few primates.
Researchers have amassed huge amounts of data over 25 years, proving that, "If treated in the right environment and in the right way, embryonic stem cells can develop into every cell in the body in fully integrated fashion."
The knowledge gained from animal studies of embryonic stem cells is extensive, reliable and "reproducible." But, says Mr. Goldstein, "We don't quite known how to take cells in a petri dish and order them to make a piece of pancreas in the dish. In animal experiments, that has not been an objective."
Now though, it is an objective in human experiments. And pursuing the research requires human stem cells because it's risky to conclude that results obtained in experiments on mice would apply to humans.
Nonetheless, the knowledge gleaned from animal experiments has convinced researchers that embryonic stem cells have value for therapy. Practitioners in practically all medical specialities forecast their eventual use.
Meanwhile, there is fresh interest among scientists in "multipotent" stem cells that become committed to a particular function or two and are found in the bone marrow of every child and adult and to a lesser extent in their blood. These are adult stem cells.
As the new National Institutes of Health document states, "At this point, there is no isolated population of adult stem cells that is capable of forming all the kinds of cells of the body. Adult stem cells are rare. Often they are difficult to identify, isolate and purify. There are insufficient numbers of cells available for transplantation, and adult stem cells do not replicate indefinitely in culture."
Recently researchers have discovered evidence indicating there are adult stem cells in the brain and other body tissues. But in many instances, the cells haven't actually been identified.
Consequently, scientists consider adult stem-cell research interesting, but at this point only potentially useful. In general, scientists are skeptical of the cells' therapeutic value if only because the research is in most cases new.
"We don't have 20 years of data and an understanding of the cells' stability and behavior as we do with embryonic cells. Besides, if all goes as it normally does in such research, many of the current studies on adult cells will turn out to be flawed or incomplete. We still have lots of questions about embryonic cells, and we have the same questions about adult cells — plus a whole lot more," Mr. Goldstein says.
Even as the research proceeds, however, stem cells will increasingly be used to treat disease. "We'll find certain things work, even though we don't know how they work," Mr. Snyder says.
"It's like aspirin. For centuries, people have been using it for pain. We just recently figured out how it works and that it can prevent stroke and heart attack." Likewise, stem cells will change medicine as scientists' depth of knowledge about them increases, Mr. Snyder concludes.



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