Wednesday, November 15, 2006

Researchers spur growth of adult brain stem cells

By Will Dunham

WASHINGTON (Reuters) - Researchers have found a way to spur the growth of neural stem cells in the brains of adult mice with an eye toward harnessing the brain's innate capacity for repair to help people with diseases such as Alzheimer's.

Determining how these stem cells can be deployed to replace cells in mice whose brains are damaged in ways resembling Parkinson's disease, Alzheimer's disease and multiple sclerosis in people is the next key step, researchers said.

The study, appearing on Tuesday in the Journal of Neuroscience, provides a fresh example of the potential for using so-called adult stem cells to treat illness by replacing cells damaged by disease or injury.

But Paul Patterson of the California Institute of Technology, senior author of the study, said it is important for scientists to continue to study embryonic stem cells as well.

Patterson and colleague Sylvian Bauer injected a natural protein from the body -- leukemia inhibitory factor, or LIF -- into a part of the brain of adult mice where stem cells reside. This fostered the production of up to six times the usual count of adult neural stem cells.

Using a person's own cells, rather than foreign cells, in future regenerative therapies avoids the transplantation of stem cells that the body's immune system might reject.

While this study involved mice, the researchers noted that human adults also harbor neural stem cells in their brains. The brains of neurodegenerative disease patients appear to try to marshal their own neural stem cells to replace dying cells, but not in the numbers sufficient to do the job.