The Stem Cell Cover-Up
By Michael FumentoInsight on the News, May 16, 2004
Copyright 2004 Insight on the News
Stem-cell research constitutes one of the most exciting areas in medical science. It promises to prevent, ameliorate and cure diseases for which there are now few if any treatments. Far easier is listing what stem cells don't have the potential to do, but here are a few of the wonders in progress:
More than 30 anticancer uses for stem cells have been tested on humans, with many already in routine therapeutical use.
By some accounts, the area in which stem-cell applications are moving fastest is autoimmune disease, in which the body's own protective system turns on itself. Diseases for which stem cells currently are being tested on humans include diabetes, lupus, multiple sclerosis, Evans syndrome, rheumatic disease and amyotrophic lateral sclerosis (Lou Gehrig's disease), among many others.
Just last February, two different human-autopsy studies demonstrated that stem cells transfused into the marrow work their way into the brain, where they can repair neurons and other vital cells. Other studies have shown that when injected into animals with severed spinal cords, stem cells rush to the injury site effecting repairs. "I think the stem cells may act as a repair squad," says the leader of one of the two studies, Helen Blau of the Stanford University Brain Research Institute. "They travel through the bloodstream, respond to stress, and contribute to brain cells. They clearly repair damage in muscle and other tissues."
At a conference in late 2002, French researchers reported that during the last 14 years they had performed 69 stem-cell transplants with an 85 percent disease-free survival rate. Since improving their procedure in 1992, all 30 of the last transplants have been successful.
Stem cells have been injected into damaged hearts and become functional muscle. This destroyed the dogma that heart muscle cannot be repaired, just as stem-cell research also wrecked the firmly held belief that brain tissue cannot regenerate.
Activists such as Christopher Reeve have it backward when they say that restrictions on funding for embryonic stem-cell research will prevent him from walking again.
Unless you've spent the last several years stranded on a deserted island, you've probably heard of at least some of these medical miracles. But here's what you may have missed. While the overwhelming majority of favorable media coverage of stem cells concerns those pulled from human embryos, called embryonic stem cells (ESCs), not a single treatment listed above has used that kind of cell. In fact, while activists such as spinally injured actor Christopher Reeve rage that but for Bush administration and congressional restrictions on ESC funding he might be walking in a few years, there are no approved treatments – and have been no human trials – involving embryonic stem cells. Each of the above therapies and experiments has involved cells that require no use of embryos.
These are called "adult stem cells" (ASCs), though they also refer to cells found in nonadult tissue such as umbilical cords, placentas and amniotic fluid. Like ESCs, they are precursors that eventually will become a mature, specialized cell. ASCs actually have been used therapeutically to treat leukemia and other diseases since the 1980s. A bone-marrow transplant is a transplant of stem cells from marrow.
Yet when an ESC so much as hiccups, it makes international news, while tremendous breakthroughs with ASCs are as a rule ignored. Welcome to what's been called "stem-cell wars," a deliberate effort to downplay the proven value of ASCs to attract more attention to the potential of ESCs. It is a war that is being fought partly over ethics, but mostly over money.
Okay, so if ASCs have such a huge advantage over ESCs then why did anybody begin researching ESCs anyway, to a point where labs and researchers all over the world now are working with them?
Blame it on the dogma – scientific dogma that is. It's long been acknowledged that ESCs carry a boatload of physiological and ethical problems. For example, ESCs implanted into animals have a nasty tendency to cause malignant tumors. That's a major hurdle to overcome, as is the fact that the body rejects them just as it rejects donated organs. Yet it was always believed that ESCs had one huge advantage over their ASC counterparts – that while an ASC could become or "differentiate" into only a few types of mature tissue with those tissues dictated by the source of that ASC, the ESCs could become any type of tissue in the entire body. In medical terminology this is known as "plasticity."
But this has never been more than theory, and lately that theory has begun crumbling under the weight of empirical findings. Or, in other words, it's had a run-in with reality.
"We do not yet know enough about adult stem cells or ESCs to make dogmatic statements of either," declared Dr. Darwin Prockop, director of the Gene Therapy Center at Tulane University, in a letter that appeared in Science.
"There's no law of physics or such that I know of that says that [ASCs] are inherently more limited than embryonic stem cells," Prockop told Citizen...
There is alot more written in this article on stem cells-at the below link:
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