Embryo-friendly technique produces stem cells

WASHINGTON (Reuters) - A company that devised a way to make embryonic stem cells using a technique it said does not harm human embryos reported on Thursday it has grown five batches of cells using this method and urged President George W. Bush to endorse it.

Massachusetts-based Advanced Cell Technology has been working with a method sometimes used to test embryos for severe genetic diseases. Called preimplantation genetic diagnosis, it involves taking a single cell from an embryo when it contains only eight or so cells.

The method usually does not harm the embryo, which is frozen for possible future implantation into the mother's womb. The ACT team also froze the embryos and used the single cell that was removed as a source of human embryonic stem cells.

Dr. Robert Lanza, ACT's scientific director, said it provides a way to create mass quantities of embryonic stem cells without harming a human embryo. Current stem cell technologies require the embryo's destruction.

"This is a working technology that exists here and now. It could be used to increase the number of stem cell lines available to federal researchers immediately," Lanza said by e-mail. "We could send these cells out to researchers tomorrow."

Embryonic stem cells are the body's master cells. They can give rise to every other cell type and are found in the earliest-stage embryos.

Researchers agree they could transform medicine. But some people including Bush object to methods that might destroy human embryos, and federal funding for such research is strictly limited.

CELLS FROM SKIN, EGGS

Companies such as ACT can do what they please, and other teams are looking for ways to make ordinary cells act like embryonic stem cells. Three teams of researchers reported progress last year in making what they call induced pluripotent stem cells -- transformed skin cells that look and possibly act like embryonic stem cells.

Another team generated similar cells using human egg cells only, a process called parthenogenesis.

But all the researchers also said scientists must continue to study true embryonic stem cells.

"If the White House approves this new methodology, researchers could effectively double or triple the number of stem cell lines available within a few months. Too many needless deaths continue to occur while this research is being held up," Lanza said.

"I hope the president will act now and approve these stem cell lines quickly."

In a letter to the journal Cell Stem Cell, Lanza and colleagues at the University of California, San Francisco, said they took single cells from five embryos, re-froze the embryos, and used the cells to grow batches of embryonic stem cells.

They thrived in lab dishes, as do true embryonic stem cells, and began to change into the various cell types, Lanza said.

"We discovered a new trick that allowed us to redirect the fate of the removed cell," he said.

"The stem cells we generated were completely normal and differentiated into all the cell types of the body, including insulin-producing cells, blood cells and even beating heart cells."

(Editing by Julie Steenhuysen and Xavier Briand)