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Bone Marrow Cells Can Become Brain Stem Cells Transplants from patient's body may someday fight Alzheimer's, Parkinson's By E.J. Mundell HealthDay Reporter THURSDAY, April 29 (HealthDayNews) -- Cells found in a patient's own bone marrow might someday be a safe, ethical source for replacing brain cells lost to Alzheimer's, Parkinson's and other neurological conditions, researchers report. The potential breakthrough may also allow doctors to bypass complex moral issues surrounding the use of stem cells derived from human embryos. "It's exciting to think that some day a person with Alzheimer's disease could use their own bone marrow to create brain cells that could potentially restore their functioning and make up for cells that were lost," lead researcher Dr. Alexander Storch of the University of Ulm, Germany, said in a statement. The research was presented Thursday in San Francisco at the annual meeting of the American Academy of Neurology. The profound disability that characterizes degenerative brain disorders such as Alzheimer's, Parkinson's, Huntington's and amyotrophic lateral sclerosis (Lou Gehrig's disease) is caused by the steady destruction of cells within the brain. Experts have long speculated that the introduction of new brain cells could restore neurological function. Stem cells are unique in that they have the potential to convert into any type of cell found in the body -- heart, bone, muscle, organ, even brain cells. Stem cell research has come under fire in recent years, however, due to moral issues surrounding the use of cells sourced from human embryos. Looking for less controversial alternatives, Storch and his team focused on a type of cell found in bone marrow called the stromal cell. "Bone marrow is the repository of a lot of tissues in the body," explained Samuel Saporta, a brain disease expert at the University of South Florida's Center for Aging & Brain Repair, in Miami. "It's the source of white blood cells and red blood cells, and the stromal cells can be the source for other kinds of tissues as well." The German researchers removed stromal cells from human bone marrow and then cultured them in the lab using special growth factors. Within a few weeks these bone marrow stromal cells had multiplied into "neuroprogenitor cells" -- brain stem cells capable of maturing into either neurons or glial cells, the two most common types of neural cells. The fact that Storch's team used human bone marrow cells is what makes this study "unique," Saporta said. "People have taken rat and mouse bone marrow and have pushed it into a neuronal, glial type of cell, but these researchers are taking from the knowledge that's been gained from the animal model and applied it to humans," he said. Saporta cautioned, however, that it's one thing to create brain stem cells, and quite another to get them to survive and thrive within the brain. "You have to get them into the brain or the nervous system someplace," he said. "They have to engraft into the nervous system and actually form some kind of functional arrangement with the existing cells, if we're talking about cell replacement therapy." So far, in experiments done with cell replacement in the human heart, "not a lot of the cells survive," Saporta noted. "That's the real challenge." Still, cells derived from a patient's own bone marrow would provide a way around certain medical and moral issues. Tissue transplants sourced from other than the patient's own body can be rejected by the body's immune system, Saporta pointed out. Suppressing this immune response with powerful drugs "is very, very onerous therapy, it's really hard on the individual and the system," he said. "If you can find a way of minimizing the amount of immunosuppression you have to do -- or not have to do any at all --- that's the ideal situation." Stem cells derived from bone marrow stromal cells also avoid moral and legal issues surrounding embryonic stem cells. "Bone marrow donations are done all the time, there are thousands done every day in the United States," Saporta said. "There's not the ethical issue here of obtaining stem cells from an embryo." Bone marrow now joins the growing list of body sites with known reservoirs of stem cells or "stem-like" cells, Saporta added. "People have already described stem-like cells in fat tissue, in bone, skin, and in tooth pulp. Each organ seems to have its own niche of stem-like cells. Even the brain has stem cells that produce neurons," he said. However, much more research lies ahead before stem cell research translates into effective bedside therapies. "The problem is that we don't understand enough about the 'instructions set' that makes the stem cell become what we would like it to become," Saporta said. "A lot more basic biology needs to be done." More information Information on stem cell research and its implications for the treatment of disease can be found at the National Institutes of Health and Northwestern University. SOURCES: Samuel Saporta, Ph.D., professor, Center for Aging & Brain Repair, University of South Florida, Miami; April 29, 2004, presentation, annual meeting of the American Academy of Neurology, San Francisco SOURCE: ScoutNews / HealthDay http://www.healthday.com/view.cfm?id=518652 Reference: Bone marrow transdifferentiation in brain after transplantation: a retrospective study Christopher R Cogle, Anthony T Yachnis, Eric D Laywell, Dani S Zander, John R Wingard, Dennis A Steindler, Edward W Scott Program in Stem Cell Biology and Regenerative Medicine, University of Florida Shands Cancer Center, Gainesville, FL, USA (C R Cogle MD, A T Yachnis MD, E D Laywell PhD, D S Zander MD, Prof J R Wingard MD, Prof D A Steindler PhD, E W Scott PhD) Correspondence to: Dr Edward W Scott, University of Florida Shands Cancer Center, 1600 SW Archer Road, ARB R4-244, PO Box 100232, Gainesville, FL 32610, USA (e-mail:[log in to unmask]) SOURCE: The Lancet http://www.thelancet.com/journal/journal.isa * * * The Bone Marrow That Turned Into Brain By Nigel Hawkes - The Times, UK April 30, 2004 ADULT bone marrow can turn itself into brain, US scientists have discovered. The finding, published in The Lancet, may have huge potential for treating degenerative brain diseases and strokes. It also provides further evidence that adult stem cells are remarkably “plastic”, adapting to new circumstances by developing into specialised cells. A team of scientists at the University of Florida, led by Edward Scott, examined brain tissue from three women who had suffered from leukaemia. As part of the treatment, they had been given bone marrow transplants from their brothers. All three women subsequently died, the longest surviving for six years after treatment. A scan of the autopsy brain tissue from all three revealed cells containing a Y chromosome, which meant they must have come from the male bone marrow donors. The woman who survived the longest after the transplant had three different types of brain cell deriving from her brother — 1 per cent of the cells in some parts of her brain came from him. This, according to the team, shows that bone marrow stem cells can migrate into the brain, be influenced by their new environment, triggering their development into specialised brain cells — or, as the authors put it, “bone marrow can make brain”. The next stage of research is to identify the cues that cause the cells to become brain cells. If they could be found and manipulated, bone marrow stem cells could be used as a source of readily harvestable cells for reconstructing brain damaged by diseases such as Parkinson’s. An advantage, especially in the US where embryonic research is controversial, is that the cells would come from adults and hence raise no ethical issues. SOURCE: The Times, UK http://www.timesonline.co.uk/article/0,,8122-1093219,00.html * * * Bone Marrow Cells Turn Into Brain Cells, Lancet Study Finds April 30 (Bloomberg) -- Stem cells from bone marrow can migrate to the brain and develop into nerve cells, suggesting bone marrow may one day be used to help repair damage caused by diseases such as Parkinson's, a Lancet study suggests. Examining the brain tissue of three dead women who had bone marrow transplants to treat leukemia, researchers at the University of Florida Shands Cancer Center found signs that the cells had spurred growth of new brain tissue. The three women had each received bone marrow transplants from their brothers. Researchers found that brain cells containing the Y chromosome, indicating male origin, were present in all three women's brains up to six years after they received bone marrow therapy. The findings suggest that the donor stem cells may have responded to a signal from an injured site in the brain, where they answered the call to generate new cells, said Edward Scott, the Lancet study's lead researcher. ``What we're seeing is part of the body's natural repair process and we're becoming more aware of how this is occurring,'' Scott, director of stem cell biology at the University of Florida, said in an interview. ``Now that we know it happens, the question is can we get it to happen better so it can become a therapy.'' The women may have suffered damage to tissue in the brain because of chemotherapy, Scott said. Transplantation of bone marrow, a source of stem cells, is performed to replace bone marrow destroyed by disease or high doses of chemotherapy or radiation. Additional research is needed to better understand the processes or ``developmental cues'' in the body that turns bone marrow cells into brain cells, researchers said. ``The promise of stem cells is that they can turn into anything when you put them in the right environment,'' Scott said. ``It's a tantalizing first step.'' To contact the reporter on this story: Angela Zimm in London at at [log in to unmask] To contact the editor of this story: Mark Rohner at [log in to unmask] SOURCE: Bloomberg http://tinyurl.com/2477y * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn