stem cells, cosmetics – and unexpected consequences

I’m starting to think about this year’s teaching: what I’m planning, what worked last year & what didn’t, things that need to be revised. One thing I’ll be doing a bit more of is ‘flip teaching’, something that worked well last semester in helping students learn about & gain an understanding of recombinant DNA technologies. I’d already found that for this particular topic, students seemed to gain far more from tutorial-group discussions rather than the lecture itself, and so tried something  a bit different. The class could view a previous lecture recording, plus look at my updated powerpoint slides, before class, and then in the actual lecture I spent about 5 minutes setting the scene, gave them some ‘starters’ for discussion (based on things that had come up in those tuts), and 10 minutes for small-group discussion (which was happy, noisy, & extremely animated) while I circulated & answered questions. Then we came up with a list of ideas & topics generated by those groups, & the discussion began. It was interesting & stimulating & fun – well, that was my impression & the class  feedback suggested that the students found it extremely valuable. Which is great as that was my hope & intention in setting things up that way.

Anyway, one of the topics was stem cells (something I blogged about quite a while ago now), & we talked quite a bit around things like ethics, as well as the practicalities. And the potential risks. Reviewing this particular class, I was reminded of a recent Scientific American article about an unexpected and undesirable outcome of a cosmetic use of stem cells. 

Now, stem cells are in the news periodically, often in relation to desperately-ill people who are willing to try just about anything in the hope of achieving a cure. And certainly there is ongoing research into the use of stem cells for things like motor neurone disease, for example. However, the US Food & Drug Administration has so far approved just one stem cell product: the use of cells derived from umbilical cord blood as a treatment for leukaemia. 

But cosmetics? Well, yes. Apparently there are quite a few cosmetic uses of stem cells out there – in fact, I’d previously come across the promotion of extract of apple stem cells as a skin rejuvenation treatment. (They are said to come from a strain of apples where the fruit keeps very well & doesn’t wither… And I must say, it was a pleasant surprise to see the Daily Mail being reasonably sceptical of this one.) But these uses can have rather unexpected consequences.

In this particular case, back in 2009 a woman had undergone a ‘facelift’ that used her own adult stem cells taken from abdominal fat: specifically, mesenchymal stem cells, which can differentiate into the cells that make up fat, bone, & cartilage. These cells had been cultured & then injected into the woman’s face, particularly the area around her eyes, where they would supposedly stimulate growth of new cells and help repair existing tissues. The process went well, but 3 months later she consulted another cosmetic surgeon, telling him that it hurt to open one eye – & that when she did, she heard a strange clicking noise. The surgeon ended up removing pieces of bone from her eyelid and the tissue around her eye – these were the source of the clicking noise, & they’d also scratched the surface of her eye.

Why bone? Because during the original treatment the doctor had injected a dermal filler, routinely used to reduce wrinkles by ‘filling’ them in. (The cynic in me wonders whether any perceived improvements in appearance were due to this, rather than the action of stem cells.) These fillers contain a substance called calcium hydroxylapatite – used by cell biologists to trigger differentiation of mesenchymal stem cells into bone; in other words, this outcome could have been predicted.

So, unregulated treatments may well pose risks for consumers. In addition, they may also indirectly affect research into possible applications of stem cells in therapies for actual, serious illness (in contrast to what one could describe as ‘vanity’ treatments), as the Scientific American article concludes:

Beyond the considerable risks to consumers, unapproved stem cell treatments also threaten the progress of basic research and clinical trials needed to establish safe stem cell therapies for serious illnesses. By harvesting stem cells, subsequently nourishing them in the lab and transplanting them back inside the human body, scientists hope to improve treatment for a variety of medical conditions, including heart failure, neurodegenerative disorders like Parkinson’s, and spinal cord injuries—essentially any condition in which the body needs new cells and tissues. Researchers are investigating many stem cell therapies in ongoing, carefully controlled clinical trials. Some of the principal questions entail which of the many kinds of stem cells to use; how to safely deliver stem cells to patients without stimulating tumors or the growth of unwanted tissues; and how to prevent the immune system from attacking stem cells provided by a donor. Securing funding for such research becomes all the more difficult if shortcuts taken by private clinics and cosmetic manufacturers – and the subsequent botched procedures and unanticipated consequences – imprint a stigma on stem cells.

I’ll be giving this article to my 2013 class to read. It should provoke some interesting discussion.


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