What if you could use fingernail clippings to grow a new liver? Or create fresh blood from a small sample of your skin? It turns out that only one of these scenarios is far-fetched.
In the most recent issue of Nature, researchers from McMasters University in Canada announced that they've successfully transformed mature skin cells into functional blood cells. The age of the skin cell doesn’t matter; skin from both young and old patients could be converted into new blood cells. The research group, led by Dr. Mickie Bhatia, has actually transformed skin cells into heart muscle and neurons in the past. What makes this recent achievement so remarkable is that the conversion from skin cell to blood cell seems to skip a hazardous dedifferentiation step – a step where the cell is first regressed into a state more like an embryonic stem cell.
It was thought that in order to transform one cell type into another, the cell had to first be reformatted, like a hard drive wiped clean, so that new programming could be installed to direct the cell to become a new cell type. This is what has always made embryonic stem (ES) cells attractive for research; ES cells are already blank slates with the ability to be programmed into any new cell. However, scientists have since realized that this dedifferentiation step often leads to the formation of tumors, a fairly nasty side effect noted in mice transplanted with reprogrammed stem cells. Dr. Bhatia believes that because direct conversion of skin to blood is more straightforward, it will also prove to be safer. Assuming all is well, the most optimistic views predict that clinical trials could begin as soon as 2012.