MS is an autoimmune disorder in which the immune system mistakenly attacks myelin, a material that covers nerves and neurons like insulation, as well as oligodendrocytes, the supporting brain cells that produce myelin. As this myelin disappears, signals become lost and disrupted, resulting in the sensory, motor and cognitive problems characteristic of the disease.

So for the new study, the researchers set out to find a way to replenish these oligodendrocytes. But to do that, the researchers had to go a few steps upstream. First, they manipulated the chemical signaling of stem cells to make them produce a type of brain cell called glia. Then they isolated a subtype of these, known as glial progenitor cells, which in turn produce new oligodendrocytes.