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On the Omaha World site.... Sanford M. Goodman said... The following link provides a concise argument for the continuation of human embryonic stem cell research, despite recent indications that stem cells may exist in adult tissues and placentas. http://www.faseb.org/opar/news/docs/adultembyonic.htm Why Adult Stem Cell Research is Not Sufficient? Laura Lyman Rodriguez, Ph.D. – FASEB Office of Public Affairs Tim Leshan – American Society for Cell Biology Quantity, potential, laboratory lifespan: We do not know whether adult stem cells have the same potential to specialize (or in this case re-specialize) into as many different cell types as embryonic stem cells have the potential to form. Beyond their ability to be re-trained as a new cell type, it is unknown, and very questionable, that they could be harvested in sufficient quantities to develop the required cell collections for research into possible disease treatment. Or, once a treatment measure was established, that a sufficient number would be available for clinical application. Should a line of adult stem cells be successfully established in the laboratory, it is not known if they will contain the same ability to grow indefinitely – and thus provide a stable supply source – as can embryonic stem cells. Adult stem cell lines may be molecularly different than their embryonic counter parts, which could cause a problem when they are used for treatment of disease. It may prove extremely difficult to obtain adult stem cells from organs such as the brain. Proof of Principle: Unlike work with adult stem cells, the potential clinical value of human embryonic stem cells is founded on more than 20 years of scientific studies with mouse embryonic stem cells, and the accumulated knowledge that has resulted from these experiments. Specifically, mouse embryonic stem cells have been used in a variety of "proof of therapeutic principle" studies in animal models of human diseases and afflictions, such as spinal cord damage, Parkinson’s disease and Alzheimer’s disease. (These mouse embryonic stem cells appear to be able to produce neural cell progenitors – useful for spinal cord damage – and reconstitute brain cells that produce chemicals for cognition, motion and sensory perception that are relevant to Parkinson’s and Alzheimer’s disease.) Regardless, it is not known if adult and embryonic stem cells are interchangeable such that they would be equally receptive to manipulations that would make them useful for therapy. Ethics and Urgency: It is likely to take years to unravel the differentiation potential and therapeutic usefulness of adult stem cells. For diseases that prove not to be treatable with adult stem cells, we risk unnecessary delays for patients suffering from these diseases, and for those that succumb to them. The source for embryonic stem cells already exists in the freezers of in vitro fertilization clinics across the country (estimated to number 100,000). These frozen cells will be legally and ethically destroyed regardless of their potential to serve the public benefit. Federal funding guarantees that the broadest array of cogent scientific questions are asked in a public arena and subject to federal oversight and ethical standards. This, in turn, will result in the greatest benefit as opportunities will be pursued for their scientific potential not for their expected commercial value. What about recent progress using adult stem cells?: The interpretation of work recently cited by members of Congress as negating the need to pursue embryonic stem cell research has been refuted by the scientists themselves. In one example, the cells utilized in the study were of fetal origin, not adult. In general, the researchers express dismay that their work, and that of their colleagues, is being used to hinder or prohibit "crucial and essential" embryonic stem cell research. Specifics regarding a reported cure for diabetes? The adult cells transplanted to produce insulin in the patients were harvested from donor pancreases. Approximately 6,000 pancreases are donated per year, but there are more than 1,000,000 individuals with type I diabetes. Results must be confirmed in a larger study before they can be implemented, and long-term safety and efficacy remain to be determined. This treatment requires patients to take a combination of three immunosuppressive drugs, which result in an increased risk of cancer and infection. Due to this high risk, this treatment is not recommended for children or individuals whose diabetes is already under control. Short summary statements: While scientists hope that fetal and adult stem cells may be therapeutically useful for some diseases in the future, embryonic stem cells currently appear to be one of the best opportunities, with perhaps the broadest potential, to treat the large variety of devastating diseases that afflict the nation’s citizens. Embryonic stem cells have many unique properties of growth, laboratory handling and cell type potential that adult stem cells have not yet been shown to have. It is too early to know which diseases adult (or embryonic) stem cells may be most suited to treat, therefore, both research avenues should be aggressively and responsibly pursued. We should not hold up the progress of embryonic stem cell research while we wait to see if adult stem cells will be useful in treating disease. http://www.faseb.org/opar/news/docs/adultembyonic.htm ******** On the Omaha World site, Sanford M. Goodman also said... Additional information can be found at http://www.nebraskansforresearch.org. Sanford M. Goodman Executive Director *********** I looked.... There are some more good links.... murray *********** ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn