December 21, 2009
Stem Cell Dangers Expected To Decrease

Dr. Shinya Yamanaka, a scientist who did key scientific experiments to turn adult cells into pluripotent stem cells is the subject of a New York Times story on the bright prospects for stem cell research. Yamanaka sees both embryonic and induced pluripotent stem cells as still risky for therapies. But he's optimistic about solving these problems.

As for the cells with which he now works, iPS cells, many hurdles remain before they are truly as versatile as the embryonic stem cells they mimic. “Embryonic stem cells are not safe,” he said. “But at the moment, iPS cells are more dangerous.”

For instance, many skin cells only partly complete the transition to stem cells, and there are no reliable markers yet to flag those that are incomplete. Embryonic stem cells also tend to form benign tumors made of a mix of muscle, bone and other cell types. For unknown reasons, Dr. Yamanaka’s stem cells are more prone to produce them. One of the trigger genes can cause cancer, and the viruses that ferry the transforming genes into a target skin cell may not deliver them where they are needed.

To turn stem cells into other cell types requires many changes in the regulatory state of the cells. DNA has many sites on it where proteins bind, methyl groups get placed, and other changes are made to regulate the behavior of tens of thousands of genes. Each type of cell in the body has a different pattern of regulation. To develop control over cell state is a very difficult undertaking.

The iPS (induced pluripotent stem) cells made by transforming adult cells (e.g a piece of skin tissue) hold much promise for two reasons. First, since creation of the cells avoids use of an embryo the iPS cells do not elicit big ethical objections. Second, iPS cells can be made using a person's own starter cells. So they are much more likely to be immunologically compatible. Dr. Yamanaka’s work in figuring out how to create iPS cells will eventually result in therapies that many of us will get. If you are still alive 30 years from now expect to get in line for stem cell therapies for all that ails you.

What I first want from stem cell therapy: the quality of eyesight I had as a teenager.

Share |      Randall Parker, 2009 December 21 10:39 PM  Biotech Stem Cells

Clarium said at December 22, 2009 1:09 AM:

"the quality of eyesight I had as a teenager?"

What? Are you myopic? Or your eyes lost the ability to focus on near objects? How would stem cells rectify this?

What do you think stem cell therapies will cost? Of course, an absolute answer is not necessary. If they are cheaper than paying for long-term care because they can prevent the decreptitude that disables people from performing the activities of daily living, then it would be a no-brainer to use these therapies. Would using stem cells to treat diseases be cheaper than current therapies? Would they create new demand, or displace existing demand with better treatments?

Lou Pagnucco said at December 22, 2009 7:52 AM:

As pointed out in Futurepundit a couple of years ago, many stem cell types in old bodies can be coaxed into functioning again by restoring (or possibly diluting) unknown factor(s) circulating in the blood.

Here are a couple of recent articles on how parabiosis restores function in tissues of old lab animals:

"A Hidden Youthfulness"

"Faulty fountains of youth: adult stem cells may contribute to aging."

Hopefully, the pharmaceutical industry is trying to identify these factors.
It seems like a big market opportunity.

Lambo said at December 22, 2009 3:49 PM:

It was the Bush adminstrations restrictions on use of embryonic stem cells which resulted in the use of iPS cells.

Randall Parker said at December 22, 2009 8:32 PM:


I need to use reading glasses. I used to have 20:15 vision. I really miss it. Incredibly handy.


Good to see you here again.

Regards the unknown factors in the blood that restrain or restore stem cell vigor: But what about the cancer risk?

I'd love to see some evidence for why we could restore some depleted factor and up-regulate stem cell activity without increased risk of cancer.

Post a comment
Name (not anon or anonymous):
Email Address:
Remember info?

Go Read More Posts On FuturePundit
Site Traffic Info
The contents of this site are copyright ©