LONDON, England – Landmark research published today by scientists in America and Japan is likely to render plans to clone human embryos redundant in the quest for revolutionary new treatments.
Both research groups have found a way to reprogram human skin cells so they cannot be distinguished from embryonic stem cells.
Although at an early stage, the technique holds out the promise of turning a scrape of cells from inside the cheek into embryonic like cells which can be used to repair almost any part of the body without having to clone human embryos, or use those donated by patients undergoing fertility treatment or abortions.
This will spur research to develop these so called stem cells into the next generation treatments of degenerative diseases such as Parkinson’s, diabetes and Motor Neuron Disease, or repair damage caused by a stroke or heart attack.
As if to underline the significance of the breakthrough, Sir Martin Evans, the British stem cell pioneer who won the Nobel prize this year, said today that his team at Cardiff University will now study the new method to help make it simpler, safer and more straightforward so it could be used on patients. “We have been waiting for this.”
The head of the Japanese team, Prof Shinya Yamanaka of Kyoto University added that it may also be possible to grow egg and sperm cells for infertility treatments, which raises the controversial possibility of growing eggs from men and sperm from women so that same sex couples could conceive a baby. “At least in theory, it’s possible,” Prof Yamanaka told The Daily Telegraph.
There is still work to be done to check and perfect the method but it looks likely to change the political and ethical landscape of this research as human embryos and eggs may no longer be needed to obtain blank slate “stem cells” capable of becoming any of the 220 types of cells in the body, though many scientists are pressing for cloning to continue in basic research.
In one study, published in the journal Science, a team of University of Wisconsin-Madison researchers led by Jungian Yu and Prof James Thomson report the genetic reprogramming of type of human skin cells, called fibroblasts, to create cells indistinguishable from embryonic stem cells.
“It’s going to completely change the field,” said Prof Thomson, adding they could be used today to create stem cells from patients with diseases to screen drugs.
The same feat is reported in the journal Cell by Prof Yamanaka with colleagues in Japan and America, the scientist who pioneered this approach of “nuclear reprogramming” in mice. He too reports that a simple recipe turns human skin cells into embryonic stem cell-like cells, he calls “iPS” cells.
“This efficiency may sound very low,” said Prof Yamanaka but in practice it means a single experiment in a Petri dish will yield several lines of embryo like cells, while cloning would require dozens of human eggs to achieve the same feat.
Although the technique is expected to speed development of new cell-based therapies, researchers caution much work remains to be done. They need to figure out how to remove the viruses used to ferry the genes into the skin cells. And the genes, one of which has been associated with cancer, need to be turned off or removed once they’ve completely their job.
The scientists also claim that research needs to continue on stem cells from human embryos to better characterize and understand the cells. These cell lines, including some produced in Canada, are created by harvesting cells from leftover embryos donated by people who have undergone fertility treatment. The embryos are days old when the cells are removed, a process that destroys the embryo. This research is legal in Canada and overseen by a federal stem cell oversight committee.
– With reports from The Daily Telegraph and National Post, Nov. 21, 2007