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Biotech / Medical : Stem Cell Research -- Ignore unavailable to you. Want to Upgrade?

To: SnowShredder who wrote (44)	8/3/2004 12:13:16 PM
From: keokalani'nui	Respond to of 495

[Ron Reagan's address at DNC 7/04] Good evening, ladies and gentlemen. A few of you may be surprised to see someone with my last name showing up to speak at a Democratic convention. Let me assure you, I am not here to make a political speech, and the topic at hand should not—must not—have anything to do with partisanship. I am here tonight to talk about the issue of research into what may be the greatest medical breakthrough in our or in any lifetime: the use of embryonic stem cells—cells created using the material of our own bodies—to cure a wide range of fatal and debilitating illnesses: Parkinson’s disease, multiple sclerosis, diabetes, lymphoma, spinal cord injuries, and much more. Millions are afflicted. Every year, every day, tragedy is visited upon families across the country, around the world. Now, we may be able to put an end to this suffering. We only need to try. Some of you already know what I’m talking about when I say “embryonic stem cell research.” Others of you are probably thinking, hmm, that’s quite a mouthful, what is this all about? Let me try and paint as simple a picture as I can while still doing justice to the incredible science involved. Let’s say that ten or so years from now you are diagnosed with Parkinson’s disease. There is currently no cure and drug therapy, with its attendant side-effects, can only temporarily relieve the symptoms. Now, imagine going to a doctor who, instead of prescribing drugs, takes a few skin cells from your arm. The nucleus of one of your cells is placed into a donor egg whose own nucleus has been removed. A bit of chemical or electrical stimulation will encourage your cell’s nucleus to begin dividing, creating new cells which will then be placed into a tissue culture. Those cells will generate embryonic stem cells containing only your DNA, thereby eliminating the risk of tissue rejection. These stem cells are then driven to become the very neural cells that are defective in Parkinson’s patients. And finally, those cells—with your DNA—are injected into your brain where they will replace the faulty cells whose failure to produce adequate dopamine led to the Parkinson’s disease in the first place. In other words, you’re cured. And another thing, these embryonic stem cells, they could continue to replicate indefinitely and, theoretically, can be induced to recreate virtually any tissue in your body. How’d you like to have your own personal biological repair kit standing by at the hospital? Sound like magic? Welcome to the future of medicine. By the way, no fetal tissue is involved in this process. No fetuses are created, none destroyed. This all happens in the laboratory at the cellular level. Now, there are those who would stand in the way of this remarkable future, who would deny the federal funding so crucial to basic research. They argue that interfering with the development of even the earliest stage embryo, even one that will never be implanted in a womb and will never develop into an actual fetus, is tantamount to murder. A few of these folks, needless to say, are just grinding a political axe and they should be ashamed of themselves. But many are well-meaning and sincere. Their belief is just that, an article of faith, and they are entitled to it. But it does not follow that the theology of a few should be allowed to forestall the health and well-being of the many. And how can we affirm life if we abandon those whose own lives are so desperately at risk? It is a hallmark of human intelligence that we are able to make distinctions. Yes, these cells could theoretically have the potential, under very different circumstances, to develop into human beings—that potential is where their magic lies. But they are not, in and of themselves, human beings. They have no fingers and toes, no brain or spinal cord. They have no thoughts, no fears. They feel no pain. Surely we can distinguish between these undifferentiated cells multiplying in a tissue culture and a living, breathing person—a parent, a spouse, a child. I know a child—well, she must be 13 now—I’d better call her a young woman. She has fingers and toes. She has a mind. She has memories. She has hopes. And she has juvenile diabetes. Like so many kids with this disease, she has adjusted amazingly well. The insulin pump she wears—she’s decorated hers with rhinestones. She can insert her own catheter needle. She has learned to sleep through the blood drawings in the wee hours of the morning. She’s very brave. She is also quite bright and understands full well the progress of her disease and what that might ultimately mean: blindness, amputation, diabetic coma. Every day, she fights to have a future. What excuse will we offer this young woman should we fail her now? What might we tell her children? Or the millions of others who suffer? That when given an opportunity to help, we turned away? That facing political opposition, we lost our nerve? That even though we knew better, we did nothing? And, should we fail, how will we feel if, a few years from now, a more enlightened generation should fulfill the promise of embryonic stem cell therapy? Imagine what they would say of us who lacked the will. No, we owe this young woman and all those who suffer—we owe ourselves—better than that. We are better than that. A wiser people, a finer nation. And for all of us in this fight, let me say: we will prevail. The tide of history is with us. Like all generations who have come before ours, we are motivated by a thirst for knowledge and compelled to see others in need as fellow angels on an often difficult path, deserving of our compassion. In a few months, we will face a choice. Yes, between two candidates and two parties, but more than that. We have a chance to take a giant stride forward for the good of all humanity. We can choose between the future and the past, between reason and ignorance, between true compassion and mere ideology. This is our moment, and we must not falter. Whatever else you do come November 2nd, I urge you, please, cast a vote for embryonic stem cell research. Thank you for your time.

To: SnowShredder who wrote (44)	11/8/2004 11:54:40 AM
From: tuck	Respond to of 495

[JunB Deficiency Leads to a Myeloproliferative Disorder Arising from Hematopoietic Stem Cells] >>Cell, Vol 119, 431-443, 29 October 2004 JunB Deficiency Leads to a Myeloproliferative Disorder Arising from Hematopoietic Stem Cells Emmanuelle Passegué,1 Erwin F. Wagner,2 and Irving L. Weissman1 1Institute of Cancer and Stem Cell Biology and Medicine, Departments of Pathology and Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305 USA 2Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria Correspondence: Emmanuelle Passegué 650-723-7389 (phone) 650-498-6255 (fax) passegue@stanford.edu The AP-1 transcription factor JunB is a transcriptional regulator of myelopoiesis. Inactivation of JunB in postnatal mice results in a myeloproliferative disorder (MPD) resembling early human chronic myelogenous leukemia (CML). Here, we show that JunB regulates the numbers of hematopoietic stem cells (HSC). JunB overexpression decreases the frequency of long-term HSC (LT-HSC), while JunB inactivation specifically expands the numbers of LT-HSC and granulocyte/macrophage progenitors (GMP) resulting in chronic MPD. Further, we demonstrate that junB inactivation must take place in LT-HSC, and not at later stages of myelopoiesis, to induce MPD and that only junB-deficient LT-HSC are capable of transplanting the MPD to recipient mice. These results demonstrate a stem cell-specific role for JunB in normal and leukemic hematopoiesis and provide experimental evidence that leukemic stem cells (LSC) can reside at the LT-HSC stage of development in a mouse model of MPD.<< Cheers, Tuck

To: SnowShredder who wrote (44)	11/11/2004 10:10:47 PM
From: SnowShredder	Read Replies (1) \| Respond to of 495

Body fat may hold bonanza: Stem cells fwiw... Best of Luck, SS philly.com >>> Posted on Sun, Oct. 17, 2004 Body fat may hold bonanza: Stem cells By Marie McCullough Inquirer Staff Writer PITTSBURGH - Every year, Americans have 150,000 gallons of fat liposuctioned out of their bodies, no doubt unaware that each pint could yield up to 200 million stem cells. But the scientists behind that calculation are acutely aware. They enjoy pointing out that the most dispensable, detested human flesh turns out to be loaded with the elusive cells that are key to the dream of regenerating and repairing body parts. That dream is fast taking shape, judging from a meeting here earlier this month of IFATS, the fledgling International Fat Applied Technology Society. It was only three years ago that a team from UCLA and the University of Pittsburgh isolated stem cells from fat, technically called adipose tissue. Since that breakthrough, a flurry of experiments, mostly in animals, have revealed these cells to be surprisingly adaptable. Given the proper cues, the cells can act like - if not actually become - bone, cartilage, nerve, heart, or blood-vessel cells. Already, fat stem cells are showing promise in reconnecting severed nerves, strengthening damaged hearts, healing inflamed intestinal holes, and cosmetically enhancing breasts. This is tantalizing evidence that "adult" stem cells - the type found in specialized tissue such as fat and bone marrow - may have greater powers of transformation than scientists thought. Maybe not as wondrous as embryonic stem cells, which can generate every tissue and organ in the body. But then, sacrificing flab to create therapies is a lot less controversial than sacrificing embryos. "We have people volunteering to donate every day," said Kacey Marra, director of Pitt's plastic-surgery research laboratory as she clicked to a PowerPoint slide of one such donation - a yellow glob of liposuctioned blubber. A genetic match If the potential pans out, fat would be an ideal source for regenerative medicines for several reasons, researchers say. A personal, or "autologous," fat supply could be readily obtained from the patient, even in an emergency. The resulting stem-cell therapy would be a genetic match, so it would not be rejected by the patient's body. And virtually everyone has fat to spare. "Stem cells have been isolated from brain tissue, but how much brain would you be willing to give up?" quipped Patricia Zuk, research director of UCLA's Regenerative Bioengineering and Repair Laboratory. "No human tissue is as dispensable as adipose tissue. That alone makes it a very advantageous source." Bone marrow - until now the most accessible source of adult stem cells for autologous use - must be withdrawn from the hip using a large needle. A cubic centimeter of bone marrow has about 500 stem cells, compared with 7,000 of the precious precursor cells in the same amount of fat, research shows. (Obese people do not have proportionately more fat stem cells, apparently because fatty-acid molecules dilute their adipose tissue.) Scientists long suspected fat stem cells existed, but the team from UCLA and Pitt, led by Zuk, was the first to publish convincing evidence. The work involved processing adipose tissue, which contains connective tissue, nerves, blood and collagen, as well as fat cells. Next, the stem cells were identified by distinctive cell-surface markers. Then, since true stem cells are able to reproduce indefinitely and "differentiate" into specialized cell types, the researchers used growth chemicals to prompt the fat stem cells in lab dishes to form colonies of cartilage, heart and bone cells. Even so, Zuk was asked at the IFATS conference how she could be sure that fat stem cells were real - not just, say, bone-marrow stem cells that have strayed into fat. "We feel relatively confident that they are a stem-cell population," she said. "I think the problem is the definition of stem cells." Some purists are not convinced that adult stem cells meet the criteria of being self-renewing and self-converting. Maybe these mature stem cells are simply merging or "fusing" with unrelated cells, thus appearing to change form and function. "Fusion," said Marra of Pitt's plastic-surgery research lab, "is a hot debate right now." Other experts say that what matters most is that fat stem cells appear to have therapeutic powers, even if the precise nature of those powers isn't clear. "It would be a home run if fat stem cells can make new heart cells," said John Fraser, who is researching such cardiovascular applications for MacroPore Biosurgery in San Diego. "But even if the stem cells are just stopping heart cells from dying, that's therapeutic." Advancing rapidly In any case, fat stem-cell research - a field in which plastic surgeons are as numerous as molecular biologists - is advancing quickly. Among the studies described at the conference: At the University of Virginia, damaged hearts in mice showed improved pumping strength a month after being injected with human-fat stem cells; autopsies showed the stem cells had become engrafted in their hearts. In another experiment, fat stem cells injected into the stroke-damaged brains of rodents migrated to the injured area, although no reparative effect was shown. At Tulane University, fat stem cells in a lab dish developed cardiac-cell characteristics, including rhythmic beating, after seven days of chemical treatment. Also, pigs with damaged hearts showed measurable cardiac improvement after treatment with stem cells from either fat or bone marrow, while the damaged hearts of untreated pigs in a comparison group got worse. In Nice, France, government researchers have used fat stem cells to repair damaged skeletal muscles in mice. At Pitt, researchers have been trying to repair severed sciatic nerves in rats. The limping rats' hind legs showed hints of improvement after human-fat stem cells, encased in a tiny biodegradable tube, were implanted at the severed spot in the nerve. Dramatic results Only one tiny study, involving five Crohn's disease patients, has been completed so far in humans, but the results were so encouraging that a new trial with 50 patients is under way, researchers at the conference said. Garcia-Olmo, a surgeon at the University of Madrid, Spain, said he had injected fat stem cells into rectal tissue to stimulate healing of surgically repaired holes in the patients' intestinal walls. These holes, called fistulas, are a recurring complication of Crohn's, an inflammatory bowel disease. Repeated surgery to close the holes can become ineffective. In the first study, within eight weeks of stem-cell treatment, 75 percent of the fistulas had completely healed. "We do not know whether the stem cells differentiate into connective or muscle or scar tissue, or secrete a growth factor" that repairs inflamed cells, Garcia-Olmo told the conference. A small trial also is under way in Tokyo to see whether fat stem cells could cosmetically enhance breasts. J. Peter Rubin, a Pitt plastic surgeon and IFATS president, hopes the treatment can be used to rebuild breasts after cancer surgery, but questions remain, including how to control shape and size. Fat stem cells remain mostly mysterious. What pudgy spot is the best source? Do the cells deteriorate with age? Are they the cellular version of career-changers, completely switching occupations, or more like temp workers or disaster-relief helpers? But MacroPore Biosurgery is not waiting for definitive answers. In August, the company, led by pioneers in fat stem-cell research, obtained the crucial first patent covering the technology. If street buzz is any predictor, their prospects are supersize: The rich and the beautiful are already bringing their liposuctioned fat to the entrepreneurs for frozen storage, banking on its future therapeutic value. "It's sort of on the QT. But we've got a lot of patients," said MacroPore president Marc Hedrick. "Some are quite famous." -------------------------------------------------------------------------------- Contact staff writer Marie McCullough at 215-854-2720 or mmccullough@phillynews.com.