Wednesday, April 3, 2013

Alan Trounson discusses iPS cell advances and a new stem cell type in his monthly update

Each month CIRM President Alan Trounson gives his perspective on recently published papers he thinks will be valuable in moving the field of stem cell research forward. This month’s report, along with an archive of past reports, is available on the CIRM website.

My reports the past few months have had many examples of people making valuable discoveries using stem cells made through reprogramming, so called iPS cells. This month has another. This one provides proof of the value of using iPS cells made from patients with genetic diseases to test drugs for toxicity in those patient populations. My colleague wrote about that work here.

But today I want to focus on a paper that surprised many people in the field, though I must admit that because it is work funded by CIRM I have been discussing it with the head of the research team for a year or more. During that time she ran exhaustive experiments to back up the findings. Those findings did initially induce head scratching because they were so unpredicted. The team led by Thea Tlsty at UCSF found a new type of cell in adult tissue that seems to be pluripotent in that it can make all kinds of tissues. But unlike a pluripotent stem cell, it is mortal; it stops multiplying and dies after a certain amount of time in a laboratory dish. You can keep pluripotent stem cells, either embryonic or iPS, growing in the laboratory indefinitely.

If other teams are able to replicate and verify this finding, these cells could potentially become a source of replacement cells for tissues from any of the three “germ layers,” of the embryo, for example to replace intestine, bone or nerves. Currently researchers working with adult cells for these repairs are limited to adult stem cells that can generally only make tissues from one of those germ layers. Much work lies ahead, but there is some possibility these cells could be a universal starting material for replacement tissue.

Thea’s team worked with breast tissue and, although they were able to isolate these unique cells, they found very few of them. Being quite rare, they could prove difficult to work with, so intriguing questions like whether they could be harnessed in the body where they reside naturally, could take a long time to answer.

One of my colleagues wrote about the work here, and UCSF issued this press release.

My full March report is available online, along with links to my reports from previous months.

A.T.

2 comments:

  1. Whatever Happened to Stem Cells

    In 1998, the stunning promise of embryonic stem cells was discovered, and it was thought that we just might be on the threshold of an age of miracles. But no miracle is a match for politics.

    But stem cells — the potential to make broken men walk again and take half a million Americans off dialysis and revolutionize our treatments for cancer? To potentially unlock the secrets to all disease? To unleash a wholly new medical field and economic engine? That was put on ice for a decade because the politics were too hard.

    "It's almost impossible to do [stem cells] in the United States," says Dr. Richard Fessler, who led what was supposed to be the first-ever human trial using embryonic stem cells for Geron before it was abruptly canceled in late 2011. "The paperwork you have to go through, the years of preparation, the politics that go on with it... So that the scientists who are interested in doing this and who have their careers staked on stem-cell research are leaving the United States."

    Dr. Ed Wirth, former medical director at Geron, recently told a conference of stem-cell doctors that what doomed the $145 million study was the burden of paying for basic research. It was the equivalent of asking a private space company to build a new rocket without any of the institutional know-how developed over decades by NASA.

    That itself is a new development in the stem-cell battle. There's no longer a zero-sum game, embryonic stem cells versus amniotic stem cells versus iPS cells. Scientists have realized that, as Rao says, there's no perfect stem cell. "Really the right cell for the right job." So we need to develop them all.

    Dr. Tom Okarma, the former CEO of Geron, now CEO of a biotech company called BioTime Acquisition, is purchasing back all of Geron's stem-cell assets — the embryonic-stem-cell lines, the equipment, the research. He's getting his old team back together. He believes that with a better economy and advances in deriving highly purified stem cells, he can finish the work he started at Geron a decade ago. They haven't published anything yet, but he says the results from that first canceled trial are in. It was safe. No tumors. Slowly, incrementally, cautiously, more trials are being outlined and planned, and everyone in the field is holding his breath that one wrong move — one patient who gets a tumor — won't doom the whole endeavor.

    Read more: Stem Cells Research - Politics of Stem Cell Research - Esquire http://www.esquire.com/features/stem-cells-research-politics-0413-5#ixzz2PVXoZiFe


    If what they say about Gern trial is true, why didn't CIRM pick up the project? With all the money floating around for fancy energy efficient subsidized cars and and money losing projects, why didn't someone step in to help change prospects for those affected by spinal cord injuries? Instead of big pay packages for the administrators and nice big buildings, why wasn't there a real fight to complete this trial? I think a lot of you guys are ethically challenged.

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  2. Dear Tom
    When Geron cancelled the spinal cord injury trial we were as disappointed as anyone. We worked hard to make the trial possible and are every bit as committed today to working with anyone who has a promising treatment for spinal cord injury, or any other disabling disorder or deadly disease. When the trial ended Geron returned all the money we had given them, with interest, and we have been using that to fund other research. Our goal is to directly address the obstacles listed in the article, namely by helping fund basic research, helping companies navigate the regulatory process, and working to move the most promising therapies into clinical trials.
    Yours
    Kevin McCormack, Communications Director, CIRM

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