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Skin makes embryonic stem cells Maggie Fox Reuters Thursday, 7 June 2007 Four studies have looked at alternative ways of producing embryonic stem cells, the body's master cells (Image: iStockphoto) Researchers have taken ordinary skin cells from a mouse and reprogrammed them to look and act like embryonic stem cells in a long-promised experiment that provides an alternative way to get these valued and controversial cells. Three studies published today in the journals Nature and Cell Stem Cell show various ways to turn the clock back and make an ordinary cell act like an embryonic stem cell, the body's ultimate master cells. A fourth, also published in Nature, showed a way to use discarded, abnormal embryos from fertility clinics to make embryonic stem cells. All the researchers worked in mice and say it will be a while before they can demonstrate their techniques using human cells. In one of the studies, Professor Rudolf Jaenisch of the Whitehead Institute in Cambridge, Massachusetts and colleagues turned mouse skin cells into embryonic stem cells. They identified four proteins, or factors, that are only active in mouse embryonic stem cells and not in adult cells. "You introduce those four factors, which induce or kick these cells into a process which we call the reprogramming process," Jaenisch says. The ordinary skin cells, which normally would only make skin and which would die in the lab after a while, instead proliferated in lab dishes. And when injected into other mouse embryos, they created chimeras, animals with the genetic characteristics of two different individuals. This opens the possibility of using stem cells to treat genetic disease, some scientists say. Japanese researcher Professor Shinya Yamanaka of Kyoto University and colleagues, who invented this technique, report similar findings in a second paper. Fertilised eggs In another report, Dr Kevin Eggan, an assistant professor at the Harvard Stem Cell Institute, and colleagues tried a different way to clone an adult cell, using a fertilised egg instead of an unfertilised one. The traditional method of somatic cell nuclear transfer involves removing a nucleus and injecting DNA into the cell. But scientists have just shown there may be another way (Image: iStockphoto) The cloning method called somatic cell nuclear transfer, used to make Dolly the sheep, involves removing the nucleus from an unfertilised egg, and replacing it with the nucleus of an adult cell. Eggan's team used abnormal embryos from fertility clinics. Some fertilised embryos at in vitro fertilisation or IVF clinics contain two or more sperm. "They cannot develop into a normal embryo," Eggan says. They have too many chromosomes, and would die. Eggan's team removed this genetic material and replaced with the DNA of an adult cell. This worked just like somatic cell nuclear transfer to get the egg dividing. Eggan calculated that tens of thousands of such abnormal embryos are created, and discarded, each year. He says both methods are being tried now using skin samples from patients who have amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig's disease, a fatal and incurable paralysing condition. Embryonic stem cells are the source of every cell, tissue and organ in the body. Scientists study them to understand the biology not only of disease, but of life itself, and want to use them to transform medicine. But their use is controversial, with opponents saying it is wrong to use a human embryo in this way. Rayilyn Brown Board Member AZNPF Arizona Chapter National Parkinson's Foundation [log in to unmask] ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn