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University of Texas Medical Branch at Galveston 11-Nov-02 Researchers Make Stem Cell Breakthrough Library: MED Keywords: STEM CELL NEURON SPINE BRAIN ALZHEIMER'S ALS Description: In a breakthrough with great significance for the use of stem cells in central nervous system therapies, researchers at UTMB have found a way to make the majority of human fetal stem cells implanted into rat brains and spinal cords develop into neurons. (Nature Neuroscience, Dec-2002) University of Texas Medical Branch at Galveston Public Affairs Office 301 University Boulevard, Suite 3.102 Galveston, Texas 77555-0144 Jim Kelly, (409) 772-8791 Pager: (409) 643-1837 [log in to unmask] EMBARGOED FOR RELEASE: 2 p.m. EST, Nov. 10, 2002 UTMB RESEARCHERS MAKE STEM CELL BREAKTHROUGH GALVESTON, Texas--For years, scientists have dreamed of using stem cells--cells that can become any cell type in the human body -- to replace neurons damaged by brain or spinal cord injury or such neurological disorders as Parkinson's disease, Alzheimer's disease or amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease). But a major obstacle has always stood in the path of making such a therapy work: Whether derived from embryonic or adult tissue, only a few stem cells transform themselves into neurons when placed in most areas of the brain and spinal cord. Most simply fail to develop, or become glial support cells, not the neurons that need to be replaced. Now, in a breakthrough with great significance for the use of stem cells in central nervous system therapies, researchers at the University of Texas Medical Branch at Galveston (UTMB) have found a way to make the majority of human fetal stem cells implanted into rat brains and spinal cords develop into neurons. A Nature Neuroscience paper entitled "Region-specific generation of cholinergic neurons from fetal human neural stem cells grafted in adult rat" (published in the journal's December issue and appearing online November 11) describes experiments by Ping Wu, Yevgeniya Tarasenko, Yanping Gu, Li-Yen Huang, Richard Coggeshall and Yongjia Yu in which they pre-treated human fetal stem cells with a mixture of chemicals important to neuron development. When injected into the prefrontal cortex, medial septum and spinal cord of adult rats -- all "non-neurogenic" regions that normally do not produce new nerve cells -- the "primed" cells almost all differentiated into neurons. Moreover, they developed into exactly the right kind of neurons for the central nervous system area into which they were implanted. "This priming seems to get the cells into a plastic intermediate stage, and then after they're injected they acquire environmental cues and become specific kinds of neurons according to where they're located," said Wu, an assistant professor of anatomy and neurosciences at UTMB. Wu, who holds a doctorate in neuroendocrinology from UTMB in addition to a medical degree, has worked for two years to find a way to get fetal stem cells to develop into cholinergic motor neurons -- nerve cells that release the neurotransmitter acetylcholine and also provide the link between the central nervous system and the muscles. "As an M.D., my ultimate goal is to find a way to help patients with neurological disorders and brain and spinal cord injury, and cholinergic neurons are what degenerate in disorders like Alzheimer's and Lou Gehrig's disease, as well as being damaged in spinal and brain trauma," Wu said. "Until now, nobody's been able to get a significant number of cholinergic neurons from primarily cultured stem cells, but using this primer we can get over 55 percent such neurons with transplanted stem cells." Funded by a new researcher grant from the Sealy & Smith Foundation and a grant from The Institute for Rehabilitation and Research (TIRR) Mission Connect project, Wu's group is continuing to investigate the possibilities for stem cell implantation -- extending the studies it has already conducted on healthy rats to those with spinal cord injury and motor neuron disease. "We will see if we can produce the same results in those diseased animals, and then the next challenge will be to see if the neurons can actually make the right contact to the right targets -- for example, if motor neurons are transplanted into the spinal cord, whether they can send fibers, or axons, to muscle," Wu said. "Then we'll see if they can release the neurotransmitters, and then look at function to see if there is a long-term functional recovery. We also need to confirm that there is no tumor formation from the implanted stem cells. Then we're talking about real clinical significance and real clinical trials. And hopefully after we sort out those critical issues, we can think about clinical applications to treat neurodegenerative diseases and spinal and brain trauma." --UTMB-- SOURCE: Newswise http://www.newswise.com/articles/2002/11/STEMCELL.TMB.html * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn