Stanford scientists reached a milestone today with their publication in Nature of research showing that human skin cells can be converted directly into functional neurons. The research, which parallels an earlier study by the group on mouse skin cells, is notable because it skips what many stem cell experts used to think was a necessary step in the transformation - that of first treating the skin cells with a variety of factors to make them very developmentally flexible, or pluripotent. In our release, senior author and stem cell expert Marius Wernig, MD, describes:
We are now much closer to being able to mimic brain or neurological diseases in the laboratory. We may perhaps even be able to one day use these cells for human therapies.
Interestingly, this direct conversion technique may offer a way around the recently reported rejection of genetically identical iPS cells by laboratory mice. That unexpected finding, which I blogged about a couple of weeks ago, has researchers worried about the potential therapeutic value of the cells. But preliminary investigations suggested that the immune response was targeted at proteins used to make the original cells pluripotent, which shouldn't be an issue with this approach. Wernig cautions against abandoning any one form of research, however:
The iPS cell approach is doable and has been shown to work. We need to keep working on both strategies. It’s possible that the best approach may vary depending on the disease or the type of research being done.