Thursday, August 30, 2007

"Personalized" Embryonic Stem Cells for Sale

Continued from page 1

By Emily Singer

However, critics say that the service is premature. Extra embryos can remain in frozen storage for years. And in the case of the paraplegic man, no treatments using neural stem cells are yet available. "There is no reason to take your embryos out of cryopreservation and make a line of stem cells and then freeze them again until the technology is available to actually use them," says Eric Chiao, a stem-cell biologist at Stanford's Institute for Stem Cell Biology and Regenerative Medicine, in Palo Alto.

Chiao and others argue that by the time scientists have figured out how to use embryonic stem cells as therapies, they will likely have developed better ways of generating the stem cells themselves, possibly using cloning, in which scientists would generate perfectly matched stem cells from an adult cell of the patient to be treated. "My offspring would be better off if they used cloning to generate stem cells for themselves," says Arthur Caplan, an ethicist at the University of Pennsylvania. "In America, the best thing you can do is take the money you would have used and invest it in an insurance policy to maximize the likelihood that your kid will have health insurance someday."

Krtolica counters that because it takes two to three months to generate the cells, it's better to have them ready before an approved use in case a client needs them immediately.

Stem-cell scientists also say that StemLifeLine's description of its product as "personalized" stem cells is misleading. As with organ transplants, cell transplants require that the immune profile of the transplanted cells match the host as closely as possible. Scientists generally use the term personalized stem cells to refer to a type of stem cell not yet possible to create: those generated through cloning, making them a perfect genetic match to the donor. Cells made from discarded embryos would not be a perfect match to family members, says Doug Melton, codirector of the Harvard Stem Cell Institute, in Cambridge, MA. "This would be like having stem cells from a sibling, so immunosuppression is still an issue."

The prospect of generating stem-cell lines from embryos is likely to ignite new ethical arguments over embryonic stem cells. Critics of embryonic-stem-cell research oppose generating stem cells from embryos for any reason. But this service could spark growth of a practice that some find even more problematic: the creation of embryos solely as a source of cells. For example, some people might want to undergo IVF expressly for the stem cells, not to have a child. Krtolica says that she hasn't yet fielded any such requests but that ultimately, it would be up to the fertility clinics. Foulk, for one, says he would not perform IVF under these circumstances.

*Due to a typo in a previous version of this piece, Russel Foulk was incorrectly stated to have said that he would perform IVF for someone who wanted to create embryos solely to generate stem cells.