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To Find Valuable Stem Cells, Some Scientists Focus On Fat Malcolm Ritter - Canadian Press Tuesday, October 05, 2004 (AP) - Dr. Robert Ersek, a 66-year-old plastic surgeon, invited reporters to his Texas operating room recently and, in front of their cameras, proceeded to liposuction himself. After numbing the skin near his navel, he slipped in a hollow tube about a half a centimetre wide and moved it back and forth until it had sucked out about 200 grams of fat. Ersek's office throws away tons of liposuctioned fat every year. But he shipped his own to a California company for processing and long-term storage of some of the cells. An international group of scientists is meeting this week in Pittsburgh to discuss the medical potential of the type of fat cell Ersek is having stored. As members of the fledgling International Fat Applied Technology Society will discuss at their meeting, fat is a little-discussed source of stem cells, those versatile biological building blocks that can morph into a variety of tissues. Fat-derived stem cells, researchers say, might someday provide replacement tissue for treating such conditions as Parkinson's disease, heart attacks, heart failure and bone defects. "We're trying to make fat do good," says IFATS president Dr. J. Peter Rubin. The fat-derived cells, which are being studied by relatively few labs, aren't the ones that store fat. Instead, they're found in between fat-storing cells. They're an example of so-called "adult" stem cells, different from the controversial embryonic stem cells. Some who oppose research into embryonic stem cells champion the cause of adult stem cells, which are found in bone marrow and elsewhere and theoretically could be taken from the very people who will be treated with them. In recent years, scientists have found evidence that adult cells can turn into a wide variety of cell types. While such studies have focused largely on cells from marrow, fat has "certainly been overlooked as a potential source of stem cells," and is probably the most practical source, says Dr. Adam Katz. Fat is easy to harvest - much easier than marrow, for example - and giving it up isn't likely to be medically dangerous. Plus, even slender people carry enough fat to yield a good supply of cells for their own treatment. Fat produces so many stem cells that there's no time-consuming need to grow more of them in the lab. "This is the only stem cell that people will pay you to take out of them," says Kevin Lee, chair of the neuroscience department at the University of Virginia. Ersek is banking his cells, but researchers say doctors may one day remove fat right when the cells are needed. The research into fat-derived cells is still in very early stages. Katz says he's not even convinced the cells deserve to be called stem cells, because he's not sure they really do turn into other kinds of cells when transplanted into the body. Nonetheless, he says they do show promise. Rubin says there's good evidence the fat-derived cells can morph into bone, cartilage, skeletal muscle, blood vessel tissue and fat, at least in the laboratory, with suggestive evidence they can also turn into heart muscle and nerve cells. Lee says people look at him askance when he talks about research into fat-derived cells, but some studies point to a possible payoff, including one by Dr. Kai Pinkernell, who says he found an encouraging result in pigs that were given experimental heart attacks. When he took fat-derived cells from the pigs and put them into the hearts of the same donor animals, those hearts began to work better. In fact, they worked just as well as hearts that received stem cells from marrow, the gold standard for this kind of experiment, he said. Dr. Marc Hedrick, president of Macropore Biosurgery Inc. of San Diego, which hopes to harness such cells to treat heart attacks, said there's good evidence the cells can become heart muscle cells. But they probably also stimulate nearby cells to make new blood vessels, heightening the therapeutic effect. "They're like orchestra leaders, we think, in terms of healing," Hedrick said. "They not only participate by playing an instrument, but they also direct some of the other people in the orchestra." In any case, Rubin figures fat-derived cells might also someday provide a way to grow replacement bone and cartilage to resurface joints damaged by arthritis. They might even be used to make more fat, for uses like breast reconstruction after surgery, he said. Researchers say they need to learn much more about just what the cells can do and how safe it would be to use them in treatment, especially what the long-term risks might be. Attempts to test the cells in humans have been scarce worldwide, but researchers said human studies in the United States might start within five years. Dr. Curt Civin, a stem cell expert, called the fat-derived cells intriguing but said he had some questions of his own: How do they compare with stem cells from elsewhere in the body, like bone marrow? Do they really live in fat deposits or are they just passing through via the bloodstream? Apart from their abundant supply, do they have any unique abilities? "When you really do the cost-benefits, do they come out, even if they're not unique, as superior in some respects?" Civin asked. "The jury is still out." Pinkernell, for one, is optimistic about finding a medical value in fat. "Not a lot of researchers in the world have realized this tissue might be a potential source of these types of cells," he said. "But I think it's just a matter of time." SOURCE: Halifax Daily News, Canada - Oct 3, 2004 http://tinyurl.com/44p2p * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn