Posted on April 13, 2008 at 8:58 PM

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By Ricki Lewis

This is the first of a two-part post. Tomorrow, Ricki will examine how this gap is widening on genetic testing.

The disconnect between what biomedical scientists know and what health care consumers believe is growing, particularly for stem cell treatments.

The ability to send a skin cell back in developmental time to reinvent itself is a giant step forward, if expected since cell biologists started cataloging stemness genes years ago, George W. Bushs partial claim to the idea notwithstanding. Even the glitch that some of those reprogramming genes cause cancer will vanish with refined recipes for making the coveted induced pluripotent stem (iPS) cells.

Researchers have also quietly coaxed pluripotent cells from the likes of testes, teeth, fat, and bone marrow, as well as from the medical trash heap, including placenta and umbilical cord membranes and even menstrual blood. Stem-like cells also hail from fetal cells lingering in womens bloodstreams and self-fertilized eggs.

So far the new contenders in the human embryonic stem (hES) cell stakes seem to be the real deal iPS cells have normal chromosomes, surfaces like those of true hES cells, and they can self-renew while also giving rise to all tissue layers of the embryo. However, because appearances can be deceiving, the International Society for Stem Cell Research warns that a great deal of work remains before these methods can be used to generate stem cells suitable for safe and effective therapies. In just a few months, though, iPS cells have proven themselves able to recapitulate more than a dozen diseases in vitro, providing unprecedented glimpses of the genesis of pathology. Their potential is staggering. Still, they are not quite ready for prime time in the clinic.

Youd never know it from the Web.



I recently lost a dear friend to amyotrophic lateral sclerosis (ALS, aka Lou Gehrigs disease). I googled ALS and stem cells, knowing all too well that the one approved drug only modestly extends life in a few patients. Within seconds, the website for an Israeli company, Brainstorm Cell Therapeutics, materialized, sharing the good news that ALS patients treated with the companys NurOwnTM therapeutic cells are expected to enjoy a rapid recovery and much enhanced quality of life. Are expected were the operative words. In fact, the company, from which my inquisitive e-mails boomeranged, is initiating a series of efficacy and safety studies toward a cure for ALS that will place human bone marrow stem cells into the mouse model used to develop the one existing drug, and then test the rodents on a rotating rod, a standard technique. Brainstorm would not have been much help to my friend.

More disturbing was EmCell, a Ukrainian company that claims the worlds (sic) largest clinical experience in embryonic stem cell transplants for various diseases and conditions. Their 16 years of international clinical experience in transplantation of human embryonic/fetal stem cells raised the first red flag, since human ES cells debuted 10 years ago, not 16. The second alert was the mention of types of ES cells, a contradiction in terms. But it was the description of their ALS therapy that revealed the mistaken identity.

The embryonic stem cells that EmCell uses to treat ALS come from cell suspensions obtained from growth zones of 4-8 weeks old cadaverous embryos systems and organs. Maybe the methods were lost in translation, but a dissected full-fledged embryo does not yield hES cells. Those cells are born in cell culture, descended from much simpler structures. Would a desperate ALS patient who pays $15,000 for the treatment know that? EmCell is selling false hope that could taint the promise of actual hES cell therapies being developed at many companies.

The gap looms between experimental and medical science. I do not think it is ethical to market treatments that have not undergone randomized, controlled clinical trials, replication, and validation.

Tomorrow: how a similar gap is opening up on genetics

Ricki Lewis is the author of the novel Stem Cell Symphony and the textbook Human Genetics: Concepts and Applications, now in its 8th edition. She is a fellow of the Alden March Bioethics Institute.