- The Washington Times - Friday, June 29, 2007

NEW YORK (AP) — Scientists say they’ve created embryonic stem cells by stimulating unfertilized eggs, a significant step toward producing transplant tissue that is genetically matched to women.

The advance suggests that someday, a woman who wants a transplant to treat a condition such as diabetes or a spinal cord injury could provide eggs to a lab to create tissue that her body wouldn’t reject.

Ethicists disagreed on whether the strategy would avoid the long-standing ethical objections to creating embryonic stem cells by other means.

Such cells can develop into virtually any tissue of the body, and scientists hope to harness them for producing specialized tissues such as nerve cells or pancreas cells to treat a range of illnesses. But the process of harvesting the stem cells destroys embryos, which many people, including President Bush, oppose.

To create tissues that genetically match a patient, some scientists are trying to develop a process called therapeutic cloning, in which DNA from the patient is inserted into an unfertilized egg to produce an embryo from which stem cells are harvested. But nobody has made that work in humans so far.

The new work tries another tack: stimulating a woman’s unfertilized egg to begin embryonic development. Scientists don’t think this development can continue long enough to produce a baby, but as the new work shows, it can produce stem cells that are genetically matched to the egg donor. Such an approach could not provide matched cells for men.

The work, published online by the journal Cloning and Stem Cells, is reported by scientists from Lifeline Cell Technology, of Walkersville, Md., and from Moscow.

Jeffrey Janus, president of Lifeline and an author of the study, noted that stem cells produced by the method might be used by patients other than the egg donor in combination with anti-rejection therapy. That’s the case with standard stem-cell lines created from ordinary embryos, he said.

Mr. Janus and colleagues report producing six lines of embryonic stem cells, one of which had chromosome abnormalities. They obtained their eggs from five women who were having eggs harvested for test-tube fertilization and who agreed to donate some for the research.

Dr. George Daley, a scientist at the Harvard Stem Cell Institute, called the work interesting.

“It’s a new type of embryonic stem-cell line from a different kind of embryo,” Dr. Daley said. “We just don’t know whether these cells will be as good as embryonic stem cells from naturally fertilized embryos.”

Ronald M. Green, a Dartmouth College ethicist, said he thinks the egg-stimulation process will prove an ethically acceptable way to create stem cells.

“People will see that these are activated eggs … [which] do not of themselves ever develop into a human being,” Mr. Green said.

But the Rev. Tad Pacholczyk, of the National Catholic Bioethics Center in Philadelphia, disagreed.

“My view is that if these grow as organized embryos for the first few days and then arrest, they may just be very short-lived human beings,” he said.



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