点击显示 收起
Aug. 24, 2006 -- Stem cells can be harvested without harming the embryos that donate them, Advanced Cell Technology scientists report.
The stem cells are plucked from embryos using a technique used to test the genetic health of preimplant embryos. The stem cells can then be grown into any other kind of human cell.
It's widely hoped that stem cells will one day be used to treat a wide variety of currently incurable diseases by regenerating damaged or diseased organs. But stem cell research has been greatly slowed by ethical objections. The main issue: Embryos are destroyed in the process of obtaining stem cells.
"This technique overcomes this hurdle and has the potential to play a critical role in the advancement of regenerative medicine," Dartmouth ethicist Ronald Green, PhD, head of ACT's ethics advisory board, said in a news release. "It also appears to be a way out of the current political impasse in this country and elsewhere."
ACT researchers Irina Klimanskaya, PhD; Robert Lanza, MD; and colleagues used a technique called preimplantation genetic diagnosis, or PGD; it is used during in vitro fertilization techniques. This basically means plucking out one of the eight cells from a blastomere, a very early stage of embryo development.
Such "biopsied" embryos are perfectly healthy and, after implantation in a woman's womb, develop into normal fetuses. More than 1,500 PGD children have been born.
The researchers cultured 19 stem-cell-like "outgrowths" derived from these harvested stem cells. From these, they were able to get two stable lines of human embryonic stem cells. Under proper conditions, these cells showed the potential to become any cell type of the human body.
Klimanskaya and colleagues predict that the technique will become more efficient in the future.
"Blastomere-derived human embryonic stem cells could be of great potential benefit for medical research, as well as for children and siblings born from transferred PGD embryos," they conclude.
The findings appear in an advance online issue of the journal Nature.
SOURCES: Klimanskaya, I. Nature, 2006; advance online publication. News release, Advanced Cell Technology.