Stem Cell Advance

Last week scientists reported that they had cloned a primate and were successfully able to harvest stem cells from the cloned embryo, raising the possibility that the same procedure could be carried out in human. Today the Washington Post reports that researchers have been able to turn human skin cells into cells similar to embryonic stem cells:

The unencumbered ability to turn adult cells into embryonic ones capable of morphing into virtually every kind of cell or tissue, described in two scientific journal articles to be released today, has been the ultimate goal of researchers for years. In theory, it would allow people to grow personalized replacement parts for their bodies from a few of their own skin cells, while giving researchers a uniquely powerful means of understanding and treating diseases.

As news of the success by two different research teams spread by e-mail, scientists seemed almost giddy at the likelihood that their field, which for its entire life has been at the center of so much debate, may suddenly become like other areas of biomedical science: appreciated, eligible for federal funding and wide open for new waves of discovery.

"These are enormously important papers," said George Q. Daley, a stem cell researcher at Children's Hospital Boston, who was not involved in the work. Like others, he spoke with stunned elation reminiscent of scientists' reactions in 1997 to the cloning of Dolly the sheep from a skin cell, the first proof that adult mammal cells could have their genetic clocks turned back.

Their enthusiasm notwithstanding, scientists warned that medical treatments are not immediately at hand. The new method uses genetically engineered viruses to transform adult cells into embryo-like ones, and those viruses can trigger tumors.But the cells will be instantly useful for research purposes -- "to move a patient's disease into a Petri dish," as Daley put it. And some scientists predicted that, with the basic secret now in hand, it could be a mere matter of months before virus-free methods for making the versatile cells are found.

This development is absolutely incredible. It goes beyond what the cloned primate researchers did, which was to replace the nucleus of a fertilized egg with the nucleus of an adult primate skin cell. Instead, these scientists utilized a retrovirus to transform a human adult skin cell-as if by magic-into a cell that has many of the same characteristics of an embryonic stem cell, thus eliminating the need to use a fertilized embryo at all and skipping the most contentious step in the stem cell debate. The cells are not exactly the same as embryonic stem cells, but they're close, enabling researchers to utilize them for further research even as the debate over the use of embryonic stem cells continues.