November 6, 2000

2 min read

Google Logo Add Us On GoogleAdd SciAm

Reversing Paralysis with Stem Cells

By Kate Wong

Join Our Community of Science Lovers!

Image: Courtesy of DAVID ANDERSON California Institute of Technology

Stem cells injected into the spinal fluid of newly paralyzed mice and rats can restore movement, according to a study described yesterday in New Orleans at the annual meeting of the Society for Neuroscience. Unlike most stem cell research, which has focused on repairing damage to small areas of the central nervous system (such as injuries caused by a stroke), this study is among the first to demonstrate the efficacy of stem cell treatment in restoring function over a large region of the central nervous system. Researchers say the new findings may lead to better treatments for human patients afflicted with motor neuron diseases such as amyotrophic lateral sclerosis (ALS) and spinal motor atrophy (SMA), which ultimately lead to paralysis and death.

Investigators led by neurologist Douglas Kerr of Johns Hopkins University injected neural stem cells (like those shown in the photograph) into the cerebrospinal fluid of 18 rodents infected with the Sindbis virus, which normally leads to permanent paralysis. Several weeks later the cells had migrated from the injection site at the based of the spinal cord up to the so-called ventral horn, a region that contains the bodies of motor nerve cells. "After eight weeks we saw definite functional improvement in half of the mice and rats," Kerr reports. "From 5 to 7 percent of the stem cells that migrated to the spinal cord appeared to differentiate into nerve cells."

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Exactly how so few nerve cells can confer this considerable improvement in function is a question the team is working to explain. "It could be that fewer nerve cells are needed for function than we suspect," Kerr surmises. "The other explanation is that the stem cells themselves haven¿t restored the nerve-cell-to-muscle units required for movement but that, instead, they protect or stimulate the few undamaged nerve cells that still remain." Whatever the answer, the results do offer hope. "Under the best research circumstances," says team member Jeffrey Rothstein, "stem cells could be used in early clinical trials within two years."

Kate Wong is an award-winning science writer and senior editor for features at Scientific American, where she has focused on evolution, ecology, anthropology, archaeology, paleontology and animal behavior. She is fascinated by human origins, which she has covered for nearly 30 years. Recently she has become obsessed with birds. Her reporting has taken her to caves in France and Croatia that Neandertals once called home to the shores of Kenya’s Lake Turkana in search of the oldest stone tools in the world, as well as to Madagascar on an expedition to unearth ancient mammals and dinosaurs, the icy waters of Antarctica, where humpback whales feast on krill, and a “Big Day” race around the state of Connecticut to find as many bird species as possible in 24 hours. Wong is co-author, with Donald Johanson, of Lucy’s Legacy: The Quest for Human Origins. She holds a bachelor of science degree in biological anthropology and zoology from the University of Michigan. Follow her on Bluesky @katewong.bsky.social

More by Kate Wong

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe