Feb 2, 2011

Improved Technique for Producing Adult Stem Cells

As I wrote about on this blog here, and at greater length for the Public Discourse, stem cell scientists continue to develop faster and safer techniques for developing induced pluripotent stem cells (iPS cells) from adult tissue. Last fall, a team at the Harvard Stem Cell Institute pioneered a method that used mRNA to produce iPS cells from skin cells, an important improvement over techniques that used viruses and created an elevated risk of cancer for patients receiving stem cell treatment.

In January, a paper published in the journal Cell Research demonstrates an improvement over the mRNA technique. [1] Rather than mRNA being used to produce iPS cells from skin cells, a fragment of DNA is used to produce iPS cells from blood cells. Since blood cells culture faster, the cells can be converted more quickly once they are harvested. Besides being more efficient, the technique may lower the cancer risk to patients receiving stem cell therapy, since the DNA needed for the transformation does not become a permanent part of the cells' genome.

There is an ongoing debate among stem cell scientists about whether iPS cells are just as good as embryonic stem cells for therapeutic purposes. Are they, for example, as safe and as pluripotent? An article published online in Nature today provides a nice overview of the state of the question. Both kinds of stem cells, it seems, have their limitations, and it is not yet clear whether either one is superior for therapeutic use.

These are important issue for ethicists and policymakers to keep tabs on. Unsettled ethical and legal issues with adult stem cell research will become more pressing as the science advances.

[1] "Efficient human iPS cell derivation by a non-integrating plasmid from blood cells with unique epigenetic and gene expression signatures." Cell Research.