The new findings, reported online today (Jan. 30, 2005) in the journal Nature Biotechnology by scientists from the University of Wisconsin-Madison, are important because they provide critical guideposts for scientists trying to repair damaged or diseased nervous systems.
Motor neurons transmit messages from the brain and spinal cord, dictating almost every movement in the body from the wiggling of a toe to the rolling of an eyeball. The new development could one day help victims of spinal-cord injuries, or pave the way for novel treatments of degenerative diseases such as amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease. With healthy cells grown in the lab, scientists could, in theory, replace dying motor neurons to restore function and alleviate the symptoms of disease or injury.
Much sooner in the future, the advance will allow researchers to create motor neuron modeling systems to screen new drugs, says study leader Su-Chun Zhang, an assistant professor of anatomy and neurology in the Stem Cell Research Program at the Waisman Center at UW-Madison.
Scientists have long believed in the therapeutic promise of embryonic stem cells with their ability to replicate indefinitely and develop into any of the 220 different types of cells and tissues in the body.
But researchers have struggled to convert blank-slate embryonic stem cells into motor neurons, says Zhang. The goal proved elusive even in simpler vertebrates such as mice, whose embryonic stem cells have been available to scientists for decades.
One reason scientists have had difficulty making motor neurons, Zhang believes, may be that they are one of the earliest neural structures to emerge in a developing embryo. With the ticking cloc
Source:University of Wisconsin-Madison