Here's the skinny from my one of my favorite journalists, Kristen Philipkoski:
Stem Cells Key to Diabetes Cure.
Dr. Fred Levine, an associate professor of pediatrics at the University of California at San Diego, is doing similar work."There's a lot of ambiguity about what constitutes a stem cell, and it's becoming less and less clear, rather than more, in this field," Levine said.
He and his colleagues have succeeded in forcing insulin-secreting beta cells to grow in culture, which causes them to revert to an earlier stage of development.
The problem is, cells like to do one of two things: revert to an earlier stage of development and replicate indefinitely, or differentiate into a specific type of cell.
Here's the full text of the article in case the link goes bad:
http://www.wired.com/news/medtech/0,1286,55239,00.html
Stem Cells Key to Diabetes Cure
By Kristen Philipkoski
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2:00 a.m. Sep. 20, 2002 PDT
Diabetes sufferer Bob Marks may never again have to stick himself with an insulin injection.
Marks is part of a lucky group of about 100 diabetes patients chosen for a University of Pennsylvania clinical trial of a new procedure called islet cell transplantation. Still, Marks waited a year before doctors called to tell him they'd found a matching donor who could give him islet cells -- the cells in the pancreas that secrete insulin.
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But the 31-year-old attorney from Danville, Pennsylvania, says it was worth the wait. And even though he takes 18 pills a day to prevent the cells from being rejected, Marks has no regrets.
"Almost right away after the surgery I felt better than I have in years," he said. "I could concentrate better and my mind was clear because my sugars weren't going high, then super low."
Marks still has to inject three-quarters the amount of insulin he needed before the surgery, but the life change is extreme, he said.
The biggest plus: Since the cells were transplanted into his liver, his body now gives him warning signs when his blood sugar is low. Before, it could sneak up on him. He no longer fears blacking out while driving his 11-year-old son to school, or arguing a case in court.
Marks is waiting for a second donor, which could eliminate his need to inject insulin, as it has for many other clinical trial participants.
Unfortunately, there are not nearly enough donors to go around. Seven hundred thousand people in the United States have type 1 diabetes (islet cell transplantation can't treat most cases of type 2 diabetes).
Meanwhile, only 6,000 donor organs were available last year -- 2,500 of which were not viable for donation. Moreover, most patients need two transplantations to get off insulin injections.
"Islet cell transplantation is wildly successful in the sense that it's been done in living people who are off insulin and leading a normal life. But it can only help a few people as opposed to many," said Dr. Robert Goldstein, chief scientific officer of the Juvenile Diabetes Research Foundation.
If the FDA approves islet cell transplantation, which could take three more years, doctors and hospital administrators will have to find a fair way to decide who will qualify for the procedure first.
"The bad news is that with this protocol, there are only enough donor pancreases in the country to meet the needs of 0.2 to 0.5 percent of those who need them. It's an ethical issue who gets them," said Dr. Joel Habener, director of the molecular endocrinology laboratory at Massachusetts General Hospital and Harvard Medical School.
Habener has an answer. Unfortunately it's unattainable, at least for now.
"The solution is to make islets in the lab," he said.
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Stem Cells Key to Diabetes Cure
2:00 a.m. Sep. 20, 2002 PDT
(page 2)
No one has figured out how, but they've gotten closer using stem cells -- both the controversial embryonic stem cells, and the kind taken from adults.
The political and ethical debate surrounding stem cells has been widely reported. People who believe that life begins at conception oppose embryonic stem cell research because the cells are extracted from human embryos, which are destroyed in the process.
Embryonic stem cells have not yet "differentiated" into mature human cells, and they have the ability to become any of the 200,000 types of cells in the human body: hair, blood, skin, toenail and so on.
Embryonic stem cell opponents cite adult stem cells, taken from adult bone marrow, blood or brains, as an answer to the ethical conundrum. But a study published recently in Science by Stanford researchers raised serious questions about the viability of these cells as therapies.
In August 2000, President Bush limited federally funded stem cell research to cells that had already been taken from 64 embryos; that number was bumped up to 72 stem cell "lines" (called that because they can replicate indefinitely) a year later.
Amidst the political and ethical controversy, scientists like Habener continue the search for a diabetes cure.
In July, he and his colleagues reported a study in which an intestinal hormone caused stem cells taken from a pancreas to become the islet cells that secrete insulin, called beta cells, and to proliferate.
"We discovered a totally unexpected population of cells in islets and we can grow and keep them in culture for as long as we want to keep them," he said.
Not surprisingly, scientific controversy exists on top of the ethical one.
Since Habener's research has not yet been replicated, it's not certain that stem cells even exist in the pancreas, let alone whether they can really proliferate new insulin-producing cells.
Dr. Fred Levine, an associate professor of pediatrics at the University of California at San Diego, is doing similar work.
"There's a lot of ambiguity about what constitutes a stem cell, and it's becoming less and less clear, rather than more, in this field," Levine said.
He and his colleagues have succeeded in forcing insulin-secreting beta cells to grow in culture, which causes them to revert to an earlier stage of development.
The problem is, cells like to do one of two things: revert to an earlier stage of development and replicate indefinitely, or differentiate into a specific type of cell.
"We force (beta cells) to grow, then we will try to do our best using various tricks of genetic modification to try to keep that growing cell in a state such that it remembers that it was a beta cell," Levine said.
In the meantime the Juvenile Diabetes Research Foundation (JDRF) -- which is free of President Bush's stem cell research restrictions because it raises money privately -- has funded several embryonic stem cell studies around the world.
The studies are in the early stages, but many scientists think they hold the most promise for success because they say embryonic stem cells are the most flexible kind.
"The field of (embryonic) stem cell research is clearly one of the most promising because it has such a wide impact. We're not just studying stem cells for one disease, it has broad implications for treating disease and understanding human development," said the JDRF's Goldstein.
And the success of islet cell transplantation only gives researchers another reason to hope for the same success with stem cell research.
"It gives us the clinical success story, it provides the basis for us wishing to do stem cell research," Goldstein said, "so we can get an unlimited supply (of islets), instead of a limited supply."
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