Cells Weekly – November 25, 2012

by Alexey Bersenev on November 25, 2012 · 0 comments

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This is a digest of news and events in stem cell research and cell therapy – Cells Weekly. During the last month of the year, we will summarize results and analyze the most significant discoveries and achievements. We’re going to pick “the method of the year”, the best scientific publications, the most interesting discussions on the web, the best blog posts and notable industry events. In order to do that, we would love to hear your opinions. Please send us your suggestions via comments of contact.

1. Discovery of genetic mosaicism and its significance
It was the paper of the week. Researchers used iPS cell generation model to study genomic differences between the lines and discovered phenomenon of genetic mosaicism between single fibroblasts, from which iPS cells were originated. In other words, our cells are not genetically identical. This is a big discovery in cell biology! I’d highly recommend you to read 2 blog posts about this paper – by Jalees Rehman and by Paul Knoepfler:

… what does this paper mean for iPSCs and the stem cell field?
Well, on the one hand, the fact that tons of genomic changes do NOT seem to occur during iPSC formation itself seems like good news. However, they did find on average two large (10kb or bigger) CNVs per iPSC cell line that had occurred during the production of those iPSC so that’s still potentially a problem. In addition, the fact that human cells are so mosaic to begin with also presents a challenge because it means that if you generate many iPSC lines from a single patient, they are likely to be genomically heterogeneous. This could have huge implications for issues such as biological function of the iPSC and their derivatives, but also for immunologic recognition of iPSC therapies by a seemingly autologous recipient.

2. Mesencymal stromal cells infusion for treatment of type 1 diabetes
Results of Chinese clinical study were published online in Endocrine J and freely available. Trialists used umbilical cord Wharton’s jelly-derived mesenchymal stem cells expanded ex vivo in 4 passages. The trial was randomized and double-blinded. The authors reported good results. However the number of patients was low – 15 in “cells group” and 14 in placebo group.

3. Detailed study of conditionally reprogrammed cells
We’ve written about conditional immortalization method this year. Richard Schlegel’s group from Georgetown University continues to explore this methodology. This week, new study shed more light on a properties of conditionally immortalized cells:

The induction of CRCs is rapid (occurs within 2 d) and results from reprogramming of the entire cell population rather than the selection of a minor subpopulation. CRCs do not overexpress the transcription factor sets characteristic of embryonic or induced pluripotent stem cells (e.g., Sox2, Oct4, Nanog, or Klf4). The induction of CRCs is also reversible, and removal of Y-27632 and feeders allows the cells to differentiate normally.

We’re very excited about the possibilities of this new method and will continue to follow it!

4. Ethical and moral issues around iPS cells could be underestimated
Excellent thought-provocative post on Signals blog, ask the question:

Will iPS cells move into the same space as ES cells?

The strongest claims preventing iPS cells from truly being considered ES cells’ equivalent is that they still require ES cells to shepherd development of an organism.
This might not always be the case: What happens if researchers change the game yet again and devise ways to transform iPS cells from ES cell counterparts to their lab-grown alter ego?

If iPS cells can truly be made totipotent, it will be ironic development indeed: the same techniques that solve ethical problems in mice will reopen much larger ones in humans.

You can add here the recent development in generation of sperm/ oocytes from iPS cells and you will get the whole bunch of new ethical/ moral/ political issues.

Highly recommended to read and discuss!

5. FDA moves on regulation of stem cell marketing claims
We’ve written about possible FDA involvement in regulation of “stem cell marketing claims”. This week I came across a warning letter, which supports this FDA’s intention. The agency warns a firm, which makes and sells fat processing device, about illegal stem cell marketing claims:

FDA cleared the Aquavage Systems “for use in aspirating subcutaneous fatty tissue including autologous fat collection.” However, your firm promotes and distribute its device for uses for which it does not have FDA clearance. Specifically,your firm’s websites (www.mdresource.com and www.aquavage.com) make numerous claims for the Aquavage Systems that are not covered by the above-identified 510(k). Examples include:

1. “The Aquavage is a highly versatile fat grafting system for high and low volume autologous fat transfer. Designed for liposculpture, body contouring, buttock and breast augmentation and stem cells derived from adipose tissue.”

This is a good news!

6. NeoStem CEO on FDA regulation stem cells as drugs
To continue regulation topic, I’d like to share very interesting post from recent GEN – Understanding FDA Oversight of Cell Therapies. NeoStem CEO, basically represents the opinion of compliant industry:

Contrary to the view that FDA oversight and guidance of regenerative medicine will slow progress, one could cogently argue that an appropriate regulatory framework will actually enhance advancement of the field. Instead of squelching innovation, these steps provide consistency and predictability for medical product developers.

That, in turn, will allow investors to make smarter decisions, doctors and patients to better understand products, and insurance companies to integrate economic analyses into more rapid coverage determinations.

She argues that the notion “FDA regulate your own cells” is rather distorting the reality:

The FDA is not regulating our cells, per se, and articles with provocative titles such as “The FDA Wants to Regulate Your Cells” run the risk of both missing the mark and oversimplifying the issue. FDA is regulating the process by which cells are turned into a therapeutic under certain conditions that they feel may present risks to individuals in order to assure both safety and efficacy for the intended purpose. In this way, the field of regenerative medicine can gain public trust, as have the drug, device, and biologics industries that preceded it.

7. An update on stem cell treatment fraud case
We’ve written about the case of stem cell treatment fraud, which is under federal trial on a court in Las Vegas. This week, an update was posted:

Henderson pediatrician Ralph Conti testified in his own defense Tuesday in the third week of his federal trial on charges of defrauding chronically ill patients through an experimental stem cell implant procedure.

I think, this is very interesting case, because we can see how motivations and moral/ ethical values interplay when physician makes decision to try new experimental “stem cell procedures”. Read more here.

8. Oocytes from stem cells – Jonathan Tilly’s profile
Nature published an excellent piece on Jonathan Tilly and oocyte stem cells controversy:

But his work has been dogged by doubt. Some researchers question his methods and reasoning. Others have tried, and failed, to repeat his experiments. Tilly “always makes what I call ‘big satellites’, something tremendous in the sky,” says molecular biologist Kui Liu at the University of Gothenburg in Sweden. “He exaggerates,” Liu says, and produces a “big press release”. “A few years later, people realize, ‘Oh, not right’.”

Very interesting read!

That’s all for the week. Please send us your suggestions about “the best of method/ news/ paper/ event/ blog post/ scandal… of the year”.


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