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Researchers find 'ultimate stem cell' - Cells in adult marrow offer hope for future medical miracles Friday 4 May 2001 - WASHINGTON -- An adult stem cell that may be able to create any organ in the body has been discovered in bone marrow, offering wide-ranging promise for curing disease similar to that of embryonic stem cells but without the ethics debate, researchers said yesterday. Dr. Neil Theise of New York University School of Medicine, who made the discovery along with Dr. Diane Krause of Yale University School of Medicine, said the finding in a study involving mice provides the strongest evidence to date that the adult body harbours stem cells that are as flexible as embryonic stem cells. The findings appear in the journal Cell. Dr. Theise said that, in theory, any organ in the body could be repaired using cells generated from this stem cell, and bone marrow-derived cells could be used to target gene therapy to a specific organ. "This would appear to be the ultimate stem cell -- or the closest we've gotten to it," Dr. Theise said. But Dr. Theise and Dr. Krause said their study should not be used to justify squelching research into embryonic stem cells. In the experiment, female mice were irradiated and received a single, male-derived bone marrow cell transplant. The scientists then used the Y chromosome, a marker for male cells, to identify all of the progeny of that one cell in the body of the female mice. As expected, they found the male chromosome in the bone marrow and blood, but were astonished to find it also in tissue from the lung, esophagus, stomach, small and large intestine, liver and skin. The researchers said it appears the cell can generate most, if not all, of the organs in the body. They said it was a good assumption the finding would apply to humans. Stem cells are master cells that, with chemical prompting, can develop into different types of cells, offering the possibility of providing treatments for a variety of maladies, including diabetes, cystic fibrosis, heart disease, Alzheimer's disease, Parkinson's disease, stroke and spinal cord injury. Stem cells can come from adult tissue -- as was the case in this study -- as well as from the cells of aborted fetuses and from blood cells from umbilical cords. Anti-abortion advocates oppose the use of embryonic stem cells. Some opponents of embryonic stem cell research point to the promise shown by recent studies involving adult stem cells. "It's of grave concern to me that our data not be used as an argument for discontinuing work on embryonic stem cells and fetal tissue," Dr. Krause said. "The reason for that is that as exciting as our data are, they really are just the beginning. We're really at the beginning of this field of understanding stem cells, stem cell plasticity, all these potentials and which cells have it. And if we discontinue embryonic research and fetal tissue research, we'll slow the field down," Dr. Krause added. "To close down those options prematurely, I think, is to close down the possibility of curing people. There's a long way to go between what the potential of something is and what its actual practicality is," Dr. Theise added. In the two-part study, stem cells in the bone marrow were isolated and purified. Some of the cells were labelled with a fluorescent colour. These cells then were injected into female mice that had been irradiated, which destroys the cells in the bone marrow. After two days, the stem cells were recovered from the bone marrow of the female mice, and only those cells with the brightest colour were used in the next part of the study. The bright colour indicated that the cells had not yet divided, assuring the scientists that the cells had the greatest likelihood for transforming into other types of cells. In the second part, a single one of the bright-coloured cells was plucked out of solution and transplanted into other female mice that had been irradiated. By killing the bone marrow, the stem cell would be forced to generate cells to repopulate the bone marrow of the recipient female mouse. Thirty female mice received the lone stem cell. Five of the mice survived 11 months. Cells containing Y chromosomes were found in multiple organs in all five surviving mice. by Will Dunham, Reuters Copyright 2001 CanWest Interactive, a CanWest company. All rights reserved http://www.ottawacitizen.com/national/010504/5013931.html . janet paterson, an akinetic rigid subtype, albeit perky, parky PD: 54/41/37 CD: 54/44/43 TEL: 613 256 8340 EMAIL: [log in to unmask] "a new voice" home page: http://www.geocities.com/janet313/ . "new voice news" latest posts: http://groups.yahoo.com/group/nvnNET/ . ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn