By Steve Sternberg, USA TODAY

Scientists have changed bone marrow cells into nerve cells, an advance that could lead to treatments for stroke, Alzheimer's disease and spinal injuries, researchers said Monday.

"We can now reliably convert 80% of these cells into neurons," says lead researcher Ira Black of the University of Medicine and Dentistry of New Jersey.

"It's a very important paper," says neurologist John McDonald of Washington University in St. Louis. "For the first time, they've developed really excellent methods for deriving only neurons, and not other kinds of cells, from bone marrow cells in rats and humans."

The method has some advantages over the use of embryonic stem cells, which scientists covet because stem cells readily turn into any cell type in the body. The federal government won't finance experiments using stem cells from embryos, and bone marrow cells are easier to obtain than neural stem cells, which must be taken from brain tissue.

Black and his team have shown that by exposing bone marrow cells to certain chemicals, they can take them back to an earlier stage of development, before the cells became bone marrow cells, and change them into nerve cells.

McDonald and Black both note that other researchers have shown the conversion is possible by simply infusing the cells into the brains of research animals.

But Black and his team were able to convert marrow cells to nerve cells in the test tube, using a combination of antioxidant chemicals and a potent growth factor, FGF.

"We were able to isolate important influences that would convert these cells," Black says.

The report, in Monday's Journal of Neuroscience Research, says, "The rapid cellular growth and self-renewal provides a virtually limitless source of cells."

Black says they may ultimately serve as an abundant source of replacements for cells that have been damaged by disease or injury.

(From US TODAY)