WASHINGTON — As lobbying continues over the question of whether Washington should fund research involving embryonic stem cells — research that inevitably requires the death of human embryos — some medical experts are insisting there is no scientific need to for such research.
New studies indicate that stem cells harvested from the umbilical cells of newborns and stored in “lifebanks,” and those taken from adult patients, may have far greater medical potential and fewer risks of dangerous side effects than using embryonic stem cells.
Stem cells have the potential to develop into tissue of any type. In recent years scientists have learned how to extract them from both embryos and adults, and are exploring their use to treat a host of diseases and disabilities. While most research so far has involved animals, the goal is human therapies.
In 1996 Congress outlawed federal support for any research that causes the death of embryos. However, the Clinton administration subsequently interpreted the law as not applying to research that utilized embryonic cells obtained from privately funded sources, and invited researchers to apply for funding.
During a visit to the National Institutes of Health Feb. 18, Health and Human Services Secretary Tommy Thompson said the Bush administration would announce a decision on embryonic stem cell research funding by the summer. Bush has previously expressed his opposition to such funding, but pro-life activists remain alarmed due to Thompson's support of embryonic stem cell research while he was governor of Wisconsin.
The presidents of more than 100 universities sent a letter to Thompson March 26 in support of the funding. Citing an earlier letter signed by 80 Nobel laureates, the presidents claimed, “It is premature to conclude that adult stem cells have the same potential as embryonic stem cells … impeding human pluripotent stem cell research risks unnecessary delay for millions of patients who may die or endure needless suffering while the effectiveness of adult stem cells is evaluated.”
Advantages of Adult Cells
David Prentice, professor of life sciences at Indiana State University and adjunct professor of medical and molecular genetics at the Indiana University School of Medicine, told the Register the debate “should already be put to rest, because the adult stem cells seem to have shown, over even just the last year, that they can do everything that the embryonic can do and do it ethically and do it without the problem of tissue rejection.”
Prentice explained that with adult cells, a patient can be treated with his own tissue, thus eliminating the problem of rejection inherent in transplants. He added that adult stem cell experiments have shown none of the medical risks associated with embryonic cells.
For example, Geron Corporation reported last fall that in one experiment, embryonic cells injected into the brain failed to generate new tissue and actually killed surrounding tissue. John Gearhart of Johns Hopkins University, a pioneer in the field, has recently reported cases in which embryonic cells caused tumors.
Prentice added that the Nobel laureates' claim that adult stem cells have less “differentiation potential” than embryonic cells is false, pointing to research showing adult cells can produce muscle, cartilage, blood, and heart, liver and brain tissue. Such cells have been used to treat leukemia for years, and recent studies indicate promise in treating many other illnesses, including strokes, arthritis, and lupus.
On Feb. 23, the company that cloned Dolly the sheep in 1997 announced it had succeeded in creating heart tissue from adult stem cells. And a group of researchers at a Feb. 18 meeting of the American Association for the Advancement of Science reported success in reprogramming stem cells (in this case, cells from a newborn's umbilical cord blood) to become brain cells.
Stem Cell Banks
In fact, umbilical cord blood is quickly becoming recognized as the most promising of all sources of “adult” stem cells. Prentice explained, “Normally in our blood as an adult maybe at most one per cent of the cells are stem cells … whereas it's something like 20% of the cells in umbilical cord blood are stem cells.”
To collect and store such cells, “cord blood banking” has begun. Families are deciding to store blood from their newborns' umbilical cords, in order to treat any future illnesses their children may have, and a small industry has grown up to meet the demand.
One such company is Lifebank in Cedar Knolls, N.J. Lifebank's chief science officer Dr. Robert Hariri told the Register that the potential of cord blood stem cells is vast.
“People now see stem cells being used to treat things like sickle-cell anemia and rheumatoid arthritis and multiple sclerosis and Lou Gehrig's disease,” Hariri said. “People are doing it not solely because of their concerns about leukemia and cancer but because they say, ‘Look, this is a resource that is available today and only today, and if we don't collect it at the time the baby is born we won't have an opportunity to collect it again.’”
In spite of the evidence in favor of adult stem cells, David Prentice doubts the advocates of embryonic cells will give up. “Whether [their] motivation is grant dollars, just getting more money into science, or the thrill of discovery, of being the first one to do this and that without any real consideration of the ethics involved, unfortunately I don't think we're going to put the scientific question to rest very soon.”
Msgr. William Smith, professor of moral theology at St. Joseph's Seminary in Yonkers, N.Y., says many scientists know that embryonic stem cell research involves the destruction of human life, but have become “numb” to that fact in order to avoid facing the issue.
Msgr. Smith said that all of the current sources of embryonic stem cells (mostly “spare” embryos from in vitro fertilization procedures) must be rejected as intrinsically immoral, apart from any benefit the cells may provide. “The problem with all of these [methods] is that they involve the intentional killing of unborn children,” he said. “It's not enough to say [human embryonic stem cell research] starts off with a little negative baggage. [It] starts with an intrinsic evil.”
But the heart of the problem, Msgr. Smith said, is society's acceptance of abortion, and that makes him doubt whether the stem cell issue will be resolved soon. “We've had 25 years of abortion now. Whether you like abortion or you don't like abortion, it has effects. It has cheapened human life,” he said “When you lower the God profile, whatever's made in the image and likeness of God is also lowered.”
David Curtin writes from Toronto.