Stem Cells without the Embryos

[andresont]

http://www.technologyreview.com/Biotech/19742/


Two groups of scientists appear to have independently achieved one of regenerative medicine's holy grails: reprogramming human adult cells to behave like embryonic stem cells, without the use of an embryo or a human egg. The method could provide a way to make patient-specific stem cells, a feat not yet achieved in humans. Such cells could eventually be used for studying complex genetic diseases, or for cell or tissue transplants without fear of immune rejection.

The new technique also removes the major ethical objections to embryonic stem-cell research: the creation and destruction of human embryos. "It's been 10 years since we derived the first embryonic stem-cell lines, which unleashed a storm of controversy that has lasted until today," says James Thomson, a biologist at the University of Wisconsin-Madison who isolated the first human embryonic stem cells in 1998 and led the new work. "I believe these results are the beginning of the end of this controversy."

Two groups--one led by Shinya Yamanaka at Kyoto University, in Japan, and one led by Thompson and Junying Yu at the University of Wisconsin--separately engineered human skin cells to express four different genes. For reasons not yet clear to scientists, exposing cells to these genes appears to turn back the developmental clock. Both groups found that the resulting cells exhibit two major properties that define embryonic stem cells. They are pluripotent, meaning that they can develop into any type of cell in the body, and they can divide apparently indefinitely in their undifferentiated state.

[IceTurf]

now they just need a cell that hasn't been damaged