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Source: GNN Genome News Network
By: Nancy Touchette
May 2, 2003
www.genomenewsnetwork.org
In February, a teenager in Michigan received injections of stem cells from his own bone marrow to repair a damaged heart. The boy had suffered a massive heart attack after being accidentally shot in the chest with a nail from a nail gun. The first choice of treatment was a heart transplant, but no donor hearts were available. Instead, doctors at Beaumont Hospital in Royal Oak, Michigan, tried a novel treatment using the 16-year-old’s stem cells.
The patient was first treated with a drug that stimulates the production of bone marrow stem cells and their release into the blood stream. Stem cells were then collected and injected into his aorta. So far, ten percent of his heart has regained function, and doctors are cautiously optimistic for greater gains.
This is an example of promising experimental therapies involving stem cells from bone marrow. Until just a few years ago, conventional wisdom held that only embryonic stem cells could turn into any cell in the body. But that thinking began to change as studies showed that stem cells from bone marrow could become heart, muscle, nerve, or liver cellsNow, the results of clinical trials conducted in Britain, Germany and Brazil show that heart patients injected with their own bone marrow cells benefit from the treatment.
In the British study, fourteen patients benefited from bone-marrow injections following heart attacks. The injections, into the scar tissue of their hearts, led to improvements in heart contraction within weeks, and the effects have persisted for more than ten months.
In the Brazilian study, fourteen patients in the late stages of heart disease improved four months after being injected with their own bone marrow cells. German researchers also reported striking improvements in five out of six heart attack patients three to nine months after receiving bone marrow cell transplants.
Bone marrow is a mixture of many cell types, including stem cells, progenitor cells, and mature blood cells. The next step, say researchers, is to identify the specific cell types that elicit the greatest response.
“Now we are in a race to find the best conditions to mobilize the bone marrow cells and make them differentiate into different types of tissues,” says Manuel Galiñanes of the University of Leicester in England, who led the British study. “We don’t know yet what cell is the one that is going to regenerate the whole tissue.”
The researchers do not yet know whether the patients improve because new heart muscle cells or new blood vessels have formed, but they suspect it may be a combination of both.
Despite these encouraging results, many researchers have expressed concerns about the treatments, pointing to the recent discovery that stem cells from bone marrow may fuse with other cells. This fusion could produce unstable cells that might trigger disease, according to some researchers.
“The cell fusion approach is not ready for the clinic,” says David Russell of the University of Washington in Seattle, who studies bone marrow stem cells in mice. “We need to show that this type of procedure is safe.“
Russell points out that bone marrow stem cells fuse with liver cells to produce hybrid cells that contain abnormal numbers of chromosomes.
“We need to show that these cells are genetically stable and will not gain or lose chromosomes and form tumors,” he says. “It’s important to know this before we talk about treating patients.”
However, Galinañes says the clinical studies should not stop while researchers try to figure out the underlying mechanisms by which bone marrow cells become heart cells.
“It is vital that we understand the mechanism,” says Galinañes. “But the reality is that our findings are already showing a benefit to people who are desperately ill. Both types of research should proceed and grow together.”
The uncertainty over how one cell type changes to another has prompted at least one prominent researcher in the field to pursue a different approach.
Now, instead of using bone marrow stem cells to treat heart disease, Piero Anversa, of the New York Medical College in Valhalla, New York, is searching for primitive cells that reside in the heart and normally replace damaged heart cells.
“We are trying to move away from these complexities by identifying resident primitive cells that are already programmed to become heart cells,” says Anversa, who was the first to show that bone marrow stem cells could replace damaged heart cells in mice.
“If we use bone marrow cells, we are asking a cell that is used to making blood to switch and now make muscle,” he explains. “The cell has to reprogram itself.”
Once these primitive heart cells are identified, Anversa says, it may be easier to devise ways to replace damaged heart tissue because these cells are already programmed to generate new heart cells. He adds that understanding the process by which heart cells regenerate may lead to new strategies to slow down aging
Stemcells are highly discussed at the moment.. Expensive operations, believes that contradict, people that reject.
But the human body produces these stemcells as well... It's self restoring. Although when we get older, the regenerative capacity becomes less and less..
But, considering the fact, there is a possability that we can help our body to boost up the production of stemcells again with a natural product that we can consume,
would this be of interest?
I would be highly interested, would you?
We take a lot of chemicals these days called medicines, with various side effects, which are sometimes even harder than the disease...
Would you consider than a natural alternative?
Let me know..
By Karen Kaplan, Los Angeles Times | April 11, 2007
LOS ANGELES -- Researchers have demonstrated for the first time that the progression of Type-1 diabetes can be halted -- and possibly reversed -- by a stem cell transplant that preserves the body's diminishing ability to make insulin, according to a study published today.
The experimental therapy eliminated the need for insulin injections for months or even years in 14 of 15 patients who were recently diagnosed with the disease. One subject, a 30-year-old male, hasn't taken insulin since his stem cell transplant more than three years ago, according to the study in the Journal of the American Medical Association.
The study suggests a new avenue for treating the intractable disease, in which the immune system destroys insulin-producing beta cells in the pancreas. Without insulin, patients can't metabolize sugar and risk developing nerve damage, cardiovascular disease, kidney failure, and blindness.
Patients with Type-1 diabetes typically compensate by monitoring their blood sugar levels every few hours and injecting themselves with insulin as many as five times a day.
After the stem cell treatment, "patients are absolutely medication-free; they're off insulin," said Dr. Richard Burt, chief of the division of immunotherapy at Northwestern University's Feinberg School of Medicine and senior author of the study.
The strategy is similar to an approach showing some success in treating other immune-system disorders, such as rheumatoid arthritis, lupus, and multiple sclerosis.
"We all realize that without addressing the problem at the level of the immune system, we'll never really beat Type-1 diabetes," said Dr. Francisco Prieto, who treats diabetics in Elk Grove, Calif., and wasn't involved in the study. "This is very encouraging work."
Burt and his colleagues cautioned that they don't yet know whether the fix is permanent and, if it is not, how long it will last. One of the subjects was insulin-free for one year but then relapsed after a respiratory viral infection, said lead author Dr. Julio Voltarelli, associate professor at Ribeirao Preto Medical School at the University of Sao Paulo in Brazil.
The researchers also cautioned that the process is not without risk, with patients vulnerable to infection during part of the therapy.
But other doctors said that even if the benefits of the therapy are temporary, the research provides valuable insight into the mechanism behind the disease.
The Juvenile Diabetes Research Foundation in New York estimates that as many as 3 million Americans have Type-1 diabetes, with between 30,000 and 35,000 new cases diagnosed each year.
The age of onset is considerably younger than for Type-2 diabetes patients, who can still make insulin but can't use it efficiently.
The stem cell approach mirrors the bone marrow transplants used to treat patients with certain cancers and blood diseases. The idea is to wipe out the faulty immune system and replace it .
In the study, 15 Brazilian patients were treated within a few months of their diagnosis, before their immune systems had the chance to eradicate all of their insulin-producing cells.
The study was conducted in Brazil because of Voltarelli's interest in the experiment. It was funded by the Brazilian Ministry of Health and other sources.
The patients, who ranged in age from 14 to 31, were treated with drugs and hormones that prompted the body to produce hematopoietic stem cells and send them from the bone marrow into the bloodstream, where they were extracted by a special machine.
About two weeks later, the patients checked into the hospital and received chemotherapy and other drugs to kill off their immune systems over five days.
After a day of rest, they were infused with their own hematopoietic stem cells, which took about eight to 12 days to establish a new immune system. In the interim, they were given antibiotics to protect against infections.
The treatment had no effect on one patient, whose disease had already progressed too far, doctors decided. Of the remaining 14 patients, 12 were able to stop taking insulin shortly after their transplants. Altogether, five patients have not needed insulin injections for at least 23 months, and two have been insulin-free for more than 18 months.
Even if patients continue to require insulin shots, the treatment should be considered a success if it halts the destruction of beta cells, said Dr. Jay Skyler, with the Diabetes Research Institute at the University of Miami Miller School of Medicine, who wrote an editorial accompanying the study.
Repost of article from the Globe Newspaper Company
© Copyright 2007 Globe Newspaper Company.
With the life expectancy of average Americans heading as high as 75 to 80 years, it is our responsibility to do everything possible to protect the quality of life of the present and future generations. A critical factor will be what we do with human embryonic stem cells. These cells have the potential to cure diseases and conditions ranging from Parkinson's and multiple sclerosis to diabetes and heart disease, Alzheimer's, Lou Gehrig's disease, even spinal-cord injuries like my own. They have been called the body's self-repair kit.
Their extraordinary potential is a recent discovery. And much basic research needs to be done before they can be sent to the front lines in the battle against disease. But no obstacle should stand in the way of responsible investigation of their possibilities. To that end, the work should be funded and supervised by the Federal Government through the National Institutes of Health. That will avoid abuses by for-profit corporations, avoid secrecy and destructive competition between laboratories and ensure the widest possible dissemination of scientific breakthroughs. Human trials should be conducted either on the NIH campus or in carefully monitored clinical facilities.
Fortunately, stem cells are readily available and easily harvested. In fertility clinics, women are given a choice of what to do with unused fertilized embryos: they can be discarded, donated to research or frozen for future use. Under NIH supervision, scientists should be allowed to take cells only from women who freely consent to their use for research. This process would not be open ended; within one to two years a sufficient number could be gathered and made available to investigators. For those reasons, the ban on federally funded human embryonic stem-cell research should be lifted as quickly as possible.
But why has the use of discarded embryos for research suddenly become such an issue? Is it more ethical for a woman to donate unused embryos that will never become human beings, or to let them be tossed away as so much garbage when they could help save thousands of lives?
Treatment with stem cells has already begun. They have been taken from umbilical cords and become healthy red cells used as a potential cure for sickle-cell anemia. Stem-cell therapy is also being used against certain types of cancer. But those are cells that have significantly differentiated; that is, they are no longer pluripotent, or capable of transforming into other cell types. For the true biological miracles that researchers have only begun to foresee, medical science must turn to undifferentiated stem cells. We need to clear the path for them as rapidly as possible.
Controversy over the treatment of certain diseases is nothing new in this country: witness the overwhelming opposition to government funding of AIDS research in the early '80s. For years the issue was a political football--until a massive grass-roots effort forced legislators to respond. Today, the NIH is authorized to spend approximately $1.8 billion annually on new protocols, and the virus is largely under control in the U.S.
While we prolong the stem-cell debate, millions continue to suffer. It is time to harness the power of government and go forward.
Article from Time.com by Christopher Reeve, Sunday, April 23rd 2000
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