Stem Cells Stop MS in Mice

In the fall of 2010, a team of scientists in California injected human stem cells into the spinal cords of mice with a crippling condition similar to multiple sclerosis, figuring that the mice would reject the cells as they might reject an organ transplant. According to Tom Lane, a University of California, Irvine pathologist who now works at the University of Utah, the research was designed to better understand the common problem of stem cell rejection. It was funded by the National Multiple Sclerosis Society and the California Institute of Regenerative Medicine. Then, two weeks later, Lane’s postdoctoral fellow, Lu Chen, noticed something else. The mice were walking. They went from being paralyzed to walking around the cage. Repeated experiments had the same results, which were published in the journal Stem Cell Reports. What works in mice may not work in humans, but the findings could lead to a possible new avenue for treating multiple sclerosis (MS), a debilitating disease affecting more than 2.3 million people worldwide. Lane said he had never seen anything like it. "This result opens up a whole new area of research for us to figure out why it worked," said co-senior author Jeanne Loring, director of the Center for Regenerative Medicine at The Scripps Research Institute in La Jolla, California. "We spent the last year convincing ourselves that the amazing results we saw were reproducible. It was just such a surprise. We’re really into mystery time now." MS is a disease in which the immune system attacks and erodes myelin, a fatty protective sheath surrounding nerve fibers. Damage to this insulating layer disrupts the transmission of nerve impulses, resulting in an array of debilitating symptoms, from numbness and tingling to blindness and paralysis. Today’s treatments mostly manage symptoms. Those drugs include anti-inflammatories and muscle relaxants. Some drugs suppress patients’ immune systems and prevent white blood cells from infiltrating the brain and spinal cord and ravaging the myelin sheath, which can slow progression of the disease. None of the current therapies repair damaged nerve tissue.