The trigger, as reported in Development, is the same as that used in mouse ES cells; it just takes longer.
Scientists from the University of Wisconsin report that they have successfully generated oligodendrocytes from human embryonic stem (ES) cells that can make myelin.
For the past decade, researchers have reportedly failed to persuade human neural stem cells to become oligodendrocytes. There has, however, been success in changing mouse ES cells into oligodendrocytes through the exposure to a protein called Sonic Hedgehog. This protein produces oligodendrocytes in the spinal cord of developing embryos.
In the current study, which will be published in May issue of Development, the investigators found that treating human ES cells with this same protein also turns them into oligodendrocytes; they just take longer to do it, 14 weeks as opposed to the two weeks taken by mouse ES cells.
They also report that a growth factor called Fgf2, which promotes oligodendrocyte development in mouse ES cells, actually stalls it in human ES cells.