It's unclear if the procedure could be the answer to the long and bitter debate over stem cell use.
By Wire services
Published August 24, 2006
NEW YORK - A California biotech company says it has found a new way of making stem cells without destroying embryos, touting it as a way to defuse one of the country's fiercest political and ethical debates.
Advocates for stem cell research seized on the new method, saying it removes the principal objection to stem cell research. Dr. Robert Lanza, an executive with Advanced Cell Technology, which created the new stem cell lines, said: "This will make it far more difficult to oppose this research."
A spokeswoman for President Bush, who vetoed legislation last month that would have allowed federal funding for embryonic stem cell research, called it a step in the right direction.
But opponents of stem cell research said the new approach still poses moral dilemmas, pointing out the possible risk to an embryo from using the technique, and the fact that it depends on in-vitro fertilization, the generation of embryos outside the womb from a couple's egg and sperm.
Stem cells have become a Holy Grail for advocates of patients with a wide variety of illnesses because of the cells' potential to transform into any type of human tissue, perhaps leading to new treatments. But the Vatican, President Bush and others have argued that the promise of stem cells should not be realized at the expense of human life, even in its most nascent stages.
Embryonic stem cells exist briefly when the embryo grows into a hollow ball of about 80 cells. Extracting these cells kills the embryo, an act that abortion foes equate with murder.
Rather than wait for stem cells to be present in the embryo, Lanza's team capitalized on the fact that an even earlier embryo - of only 8 to 10 cells - is very resilient and adaptable. Such an embryo can give up one or even two of its cells, called blastomeres, and keep developing normally. Each extracted blastomere is theoretically capable of generating all the tissue types in the body.
Using 16 such embryos, all donated by infertility clinics, Lanza's team extracted blastomeres and chemically signaled them to begin dividing in lab dishes. Then, to trigger the blastomeres to produce embryonic stem cells, the researchers embedded them with embryonic stem cells that had already grown in a separate colony.
In the end, two new human embryonic stem cell colonies were generated from 91 blastomeres. Last year, Lanza accomplished the same feat using mice cells, establishing the scientific feasibility of the approach.
Although Lanza's research did not specify the fate of the donated embryos, he said "some" managed to continue growing and were put in frozen storage at the stage where they could be implanted in a womb.
The method was described online Wednesday in the British journal Nature. The journal published a similar paper by Advanced Cell Technology last year demonstrating the technique's viability in mice.
"The science is interesting and important," said John Harris, a professor of bioethics at the University of Manchester in Great Britain, commenting on the biotech company's efforts.
"I think this will become a standard way of producing stem cell lines," said Ronald M. Green, a Dartmouth College professor of religion who is an unpaid bioethics adviser to Advanced Cell Technology.
The company, which has been struggling financially, owns about 300 patents that it hopes to develop into medical treatments. After news of its announcement broke on Wednesday, the price of its over-the-counter stock shot up from 42 cents to close at $1.83 per share.
However, both experts and critics see potential problems with the new approach.
Some stem cell researchers say the new approach, though it may hold future promise, isn't as efficient as their current method of creating stem cells.
That procedure involves the destruction of embryos after about five days of development, when they consist of about 100 cells.
"The notion that it solves some kind of a scientific, social or ethical dilemma - I can't say that it does," said molecular biologist Kevin Eggan of the Harvard Stem Cell Institute, which is trying to clone human embryos to harvest stem cells.
Meanwhile, opponents of stem cell science argue that the technique solves nothing, because even the single cell removed by the new approach could theoretically grow into a full-fledged human.
Critics also say that removing a blastomere may not be completely harmless. Infertility clinics have been using the procedure for several years to diagnose and discard embryos with certain inherited diseases. The resulting babies seem healthy, but even Lanza says more data is needed.
"We don't want to solve one ethical problem," said Princeton University constitutional law expert Robert George, "by creating another one."
The method "raises more ethical questions than it answers," said Richard Doerflinger of the U.S. Conference of Catholic Bishops.
U.S. law currently bans federal funding of any research that harms human embryos. A White House spokeswoman said the method's eligibility for funding could not yet be determined, "but it is encouraging to see scientists at least making serious efforts to move away from research that involves the destruction of embryos."
President Bush has said that he personally opposes any research that sacrifices embryonic life, even to save an existing person. In August 2001 the president limited federal funding to research on a few dozen stem cell lines that had been created up to that point.
Some scientists say the decree has severely crippled progress in the field. But recent developments have moved them toward their twin goals of attracting nonfederal money for stem cell research and overturning the restrictions.
Several states, including California, New Jersey and Illinois, have set up ways to fund the research. A number of Democratic candidates in this year's congressional elections are focusing on the issue.
