Monday, November 21, 2011

Simpler, Better

The New Scientist recently ran a rather remarkable editorial, “In praise of stem cell simplicity.”

“We should keep all avenues of stem-cell research open but be grateful when simpler alternatives emerge,” the editorial asserts.  Pointing to recent advances using adult and induced pluripotent stem cells (iPSCs), the article says these “could spawn novel, personalized stem-cell treatments that, if not simple per se, are simpler than what has gone before.”

Not only are these advances simpler (compared to using human embryonic stem cells (hESCs) to try and treat disease), but “[w]hat marks these treatments out is that they are eminently practical and ethically unquestionable. This is in stark contrast to much previous work, which has focused on human embryonic stem cells, or hESCs.”

Drawing out that contrast, the article notes that hESC research has always been ethically questionable.  It then refers to the so-called “breakthrough” in October using cloning to produce human stem cells.  However, the article notes, the process still required eggs, an embryo was still killed and the resulting stem cells were genetically malformed, “rendering them useless for medical uses.”  Three strikes and that so-called breakthrough is out.

The article specifically refers to two advances demonstrating how non-embryonic stem cell research is simpler than and superior to hESCR.  Diabetic rats cured with their own stem cells” tells how researchers transformed brain stem cells that had been extracted through the nose into insulin producing cells in the pancreas.”  The researchers did this “without genetic trickery.”

The second advance tells how scientists used stem cells taken from a baby’s own amniotic fluid to repair congenital defects such as holes in the diaphragm.

So it would certainly appear clear that non-embryonic approaches to stem cell research are turning out to be simpler and more effective in terms of actually producing therapies than hESCR.  Despite these advantages, however, the article concludes by calling for all avenues of stem cell research to continue.  For instance, the article notes, iPSCs are reprogrammed using a virus and the reprogrammed cells do not yet match embryonic stem cells.

However, the process of producing iPSCs has vastly improved in the relatively short time since they were first discovered in 2007.  Researchers have used a particular RNA viral vector that carries no risk of integrating into the host genome, to produce iPSCs that have no foreign gene insertions and that are viral/factor-free.  The researchers reported that “the resulting iPSCs expressed human embryonic stem cell markers and exhibited pluripotency.”  Another study has found that proteins produced by iPSCs and human embryonic stem cells (hESCs) are 99 percent similar.  According to one of the researchers the study suggests that iPSCs and hESCs are quite similar.  “According to some measurements, the protein production of an embryonic stem cell was closer to that of an IPS cell than to a second embryonic stem cell. “

As the Do No Harm Coalition has frequently pointed out, in 1999, when President Clinton’s National Bioethics Advisory Committee (NBAC) first recommended federal funding for hESCR, it did so conditionally: “In our judgment, the derivation of stem cells from embryos remaining following infertility treatments is justifiable only if no less morally problematic alternatives are available for advancing the research…The claim that there are alternatives to using stem cells derived from embryos is not, at the present time, supported scientifically. We recognize, however, that this is a matter that must be revisited continually as science advances.” (Ethical Issues in Human Stem Cell Research, Volume I, p.53, emphasis added).
In other words, they recognized that, given the ethical problems associated with hESCR, it should not be undertaken if viable alternatives exist.  

Such viable alternatives exist.  Advances in non-hESCR to treat disease are many, ongoing and well documented in the peer-reviewed literature.  It’s time that proponents of human embryonic stem cell research revisit, in the light of scientific advances, their earlier premature judgments on the need to pursue such destructive research.

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