Turning a cell into an induced pluripotent stem cell (iPSC) is tricky. It turns out that blood cells have an edge—they already epigenetically resemble iPSCs.
When U.S. and Chinese researchers poked around the DNA of human CD34+ cells from umbilical cord blood and adult blood, they found that the promoters’ methylation patterns looked a heck of a lot like those in embryonic stem cell and iPSC lines. In contrast, promoters in non-blood cells were methylated very differently.
Next, they worked their magic and turned blood cells into iPSCs. Here’s what they learned in the process:
- A novel plasmid expressing reprogramming factors efficiently reprogrammed CD34+ and regular ol’ non-fractionated blood cells into iPSCs without integrating into the genome.
- Cord blood-derived cells did this better than adult blood cells.
- Reprogramming was boosted when a second plasmid containing the SV40 large T antigen was included.
- Sodium butyrate provided another boost.
- With this new method, iPSCs can be created in only a few days (instead of weeks with other approaches) using only a few milliliters of blood.
The researchers also say that the results back up claims that epigenetic differences are the reason that some cells turn into pluripotent cells more easily than others.
If you wanna do a little magic of your own, check out the details in Cell Research, January 18, 2011.