Stem Cells Regenerate in the Mouse Inner Ear

Stem Cells Regenerate in the Mouse Inner Ear

CBS reported last night that scientist at Stanford have been able to use stem cells to regenerate the tiny hairs in the inner ear that are a key part of hearing. (The hairs transmit the sound signals to the nerves.) The work was done by injecting the stem cells into mouse embryos; it has yet to be done on live mice. The story, being for TV and therefore almost devoid of any real information, did not say what kind of stem cells were used. It is also belated; the San Francisco Chronicle had a story on the subject back in January, and Stanford itself, reporting in May 2005 that the scientist was coming, also spoke to the fact that pluripotent cells had been identified in ears.

The sad thing is reading the comments—people are asking desperately if they or a family member would be eligible for this treatment, or how to find out about it. If it hasn’t even happened in live mice, there is certainly no clinical study in humans going on right now. I believe that CBS has a responsibility to have stated this clearly in the story—this is indeed what I would call an example of media hype. People are not always good at understanding what information their source is giving them—I sometimes get comments to this blog asking me similar questions even when I have identified the state of the research and who is doing it—but precisely because this happens the media have a responsibility to be clear that a therapy is not imminent. People should always discuss a study with their physician, not with a journalist, even if it is a journalist who brings it to their attention. The Chronicle story quotes the researcher as saying it might take 10,000 mice and 10 years, which is the kind of info that the public needs.

Don’t get your science news from TV, folks! Print is better by far.

Australian Brain-Drain Feared

Australian Brain-Drain Feared

Now Australian researchers and scientists fear that if restrictions on embryonic stem cell research are not lifted, scientists will leave for greener pastures. The same fear has been frequently expressed about American scientists as well; the apparent recipient would be the United Kingdom, which is supportive of the field. An article on ABC (Australian) quoted two scientists who are worried that Australia is falling behind, and the Age has a similar story.

This is perceptual and has not been backed up a study with hard data, but the perception that Americans were falling behind was confirmed by a report that showed that scientists in other nations were publishing at a higher rate. So I expect that the perception has some validity.

Regenerative Protein Identified in Planaria

Regenerative Protein Identified in Planaria

Scientists have identified a protein which is necessary for planaria (freshwater flatworms) to regenerate. The worms have the ability to regenerate an entire new organism from a single piece of a chopped-up planarian. This obviously makes them interesting to stem cell researchers. (See Post of 11/25/05 for info on the smedwi-2 gene in flatworms.) Researchers at the University of Illinois used RNA interference to shut off most of the “Bruli” proteins in flatworms. The result, according to the press release, was that the stem cells migrated to the site of the injury and began repairing it but were unable to maintain their population; they did not also make replacement stem cells. One of the researchers suggested that this might be because without the Bruli protein, other proteins were expressing themselves instead and causing the stem cells to differentiate rather than to maintain themselves.

Obviously for this to have any future therapeutic applications, the researchers need to see if a similar protein exists in higher-order animals and, if so, what happens when the protein that encourages regeneration is switched on.

I will say that regeneration makes me nervous—the fact that so few animals can do it when it seems like such an obvious benefit suggests to me that it comes with some other attributes that were an evolutionary failure. In theory it seems pretty straightforward, and I certainly believe research on it should go forward, but I would be wary.