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Biotechnology Safer Stem Cells? Matthew Herper and Robert Langreth 02.27.08, 12:01 PM ET http://www.forbes.com/business/2008/02/27/biotech- research-cells-biz-cx_mh_0227stem.html A small California biotech company backed by billionaire John Tu claims to have created stem cells without destroying human embryos or introducing cancer-causing genes, in what could be a major step toward using these stem cells for human trials. But the company provided almost no details of how its method worked, leading to skepticism among many scientists. Instead of publishing its method in a scientific journal, the company, PrimeGen Biotech <http://www.primegenbiotech.com/pg08/index.php> of Irvine, Calif., released the news during a brief presentation at a stem cell industry conference in New York. That means that it sidestepped the careful anonymous vetting that normally accompanies discoveries published in journals like Science or Nature. PrimeGen's work builds on the stunning news last fall that researchers in Japan and Wisconsin had reprogrammed skin cells to make primordial stem cells without destroying embryos. Little-noted in the news reports at the time was that to make these cells, the scientists needed to introduce cancer-causing genes into the cells using gene-altered viruses. This makes the resultant cells unsuitable for human therapy, although they are a boon for lab research. PrimeGen claimed Tuesday it had circumvented this problem. Instead of genes, it uses unspecified carbon-based "delivery particles" to insert four proteins into cells to stimulate the reprogramming process. This caused some of the cells to revert to being much like embryonic stem cells, PrimeGen said. PrimeGen said it has done the experiment with retinal, skin and testicular cells. "Our goals are ambitious--we believe with this therapy, we can be in clinic in 2010," said PrimeGen president John Sundsmo in an interview. He said he couldn't release details on what the delivery particles are until the company finalizes an agreement with a corporate partner. Many outside scientists said they weren't familiar with the work and weren't quite sure what to think. "Until the work goes through [peer-review], it would be difficult to evaluate," says James Thomson, the researcher at University of Wisconsin, Madison, who created the first embryonic stem cells in 1998. George Daley, of Harvard University, said he was "pretty suspicious of publication by press release." Nonetheless, "if this is real it really is a significant step," says Arnold Kriegstein, director of the Institute for Regenerative Medicine at U.C.-San Francisco. "They could be on to something." "It's promising, but there's still a long way to go," says U.C.-Santa Barbara stem cell expert Dennis Clegg, one of the few outside scientists who has studied the cells directly. He says that so far they behave much like embryonic stem cells, but he expressed surprise over the company releasing the news. "I think we've just seen the tip of the iceberg. There are going to be a lot of ways to do this." PrimeGen's Sundsmo says the company is writing up scientific papers on the method, and plans to release more details at a stem cell scientific meeting later this year. However, he released the news at the industry conference in hopes of finding a corporate partner to help produce cells in large volumes. "We need partners to help us expand the cells," he said. The company hopes to test the cells in humans for either bone marrow transplants and eye disease treatments in as little as two years. Sundsmo announced the work Tuesday at a presentation at the Third Annual Stem Cell Summit, an industry meeting in New York, and in a follow-up interview. Embryonic stem cells are nascent bits of biological potential that could give rise to any kind of tissue in the body, potentially opening doors to treating Parkinson's, spinal cord injury and diabetes. But their use is ethically controversial because creating the cells requires destroying five-day-old human embryos. One potential advantage of the new techniques is the creation of cells that are genetically matched to patients who need cell transplants. "That would be so much better than having a stem cell where you have to worry about immune rejection," says Clegg. PrimeGen says an independent lab has tested its cells and it has brought in top researchers to vet the results. But the real test of what PrimeGen has will be what happens when the cells are implanted in rodents. If they're the real deal, they'll form a kind of tumor called a teratoma, a mixed-up collection of different kinds of tissues. Some of the studies might not use the embryonic cells, but more intermediate cells created by PrimeGen's process. Many of these cells are incompletely time-warped, but these might be perfect, for instance, for replacing dead retina cells in the eye to treat macular degeneration and prevent age-related blindness. PrimeGen was founded five years ago, and has largely been funded by entrepreneurs Tu, the billionaire founder of flash-memory drive maker Kingston Technology, and Thomas C.K. Yuen, the chief executive of audio equipment maker SRS Labs (nasdaq: SRSL <http://finapps.forbes.com/finapps/jsp/finance/com pinfo/CIAtAGlance.jsp?tkr=SRSL> - news <http://www.forbes.com/markets/company_news.jhtml? ticker=SRSL> - people <http://www.forbes.com/peopletracker/results.jhtml ?startRow=0&name=&ticker=SRSL> ). Most of its work has focused on other stem cell approaches, but more than a year ago it started working on the stem cell technique. More data on the carbon profiles will come in a week, and the research has been submitted to medical journals and a scientific conference. One reason that scientists are cautious is that the stem cell field has had more than its share of disappointments. Geron (nasdaq: GERN <http://finapps.forbes.com/finapps/jsp/finance/com pinfo/CIAtAGlance.jsp?tkr=GERN> - news <http://www.forbes.com/markets/company_news.jhtml? ticker=GERN> - people <http://www.forbes.com/peopletracker/results.jhtml ?startRow=0&name=&ticker=GERN> ), a publicly traded company testing embryonic stem cell treatments, has been promising to begin human trials of embryonic stem cells for years; it still hasn't. Far more ominously, several research claims published by Woo-Suk Hwang, a Korean researcher, turned out to be fraudulent. PrimeGen said in its presentation it is working with Thomson, the Wisconsin stem cell discoverer. But Thomson says he has not directly worked with PrimeGen. "I am not PrimeGen's collaborator, and know essentially nothing about their work," he says. Carolyn Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, champagne in one hand - strawberries in the other, body thoroughly used up, totally worn out and screaming "WOOHOO - What a Ride!" -- Attributed to an octogenarian named Mavis Leyrer, of Seattle ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn