Stem Cell Breakthrough May Lead to MS Treatments

April 10 -- THURSDAY, April 9 (HealthDay News) -- U.S. scientists say they've coaxed human embryonic stem cells into generating cells that might someday be used to repair nerves damaged by multiple sclerosis.

The researchers pushed the stem cells to grow into critical nervous system support cells called oligodendrocytes, according to a report released Thursday.

Oligodendrocytes produce the myelin sheath that surrounds nerve fibers like wire insulation. The findings represent an important step toward embryonic stem cell-based therapies in general, experts say, and also for cell-based therapies for myelination disorders such as MS in particular. At the very least, the findings should lead to a laboratory model of the illness' pathology.

"They are definitely laying the groundwork for being able to apply these cells in terms of a therapeutic application," said Timothy Coetzee, executive director of Fast Forward, a wholly-owned subsidiary of the National Multiple Sclerosis Society, which partially funded the study.

Yet at the same time, he added, "It illustrated for me the critical importance of not assuming that because you can do something with a mouse cell, that a human cell is going to behave in the same manner."

The research was published in the May issue of the journal Development.

At the heart of this study is a fundamental question: What's the difference between mouse and man?

It's not as silly as it sounds. Human experimentation being both morally and legally forbidden, researchers often use model organisms such as mice as proxies for human development. The underlying assumption, of course, is that these organisms have fundamentally the same biology as we do. Sometimes, though, that assumption turns out to be wrong.

For years, researchers using mouse embryonic stem cells (ESCs) knew that if they added one of two proteins, FGF2 or SHH, to the cells' growth media, they could reliably induce those cells to become oligodendrocytes. The human application was obvious: ESC-derived oligodendrocytes could either be used directly as a cell therapy for MS and related diseases, or serve as research tools to study them.