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[IP] New York Times report on sucessful cell implants (Sat)

(From the New York Times, 5-27-00)

May 27, 2000

Cell Transplants Offer Hope for Severe Cases of Diabetes


n an important advance, researchers in Canada are reporting that
transplants of insulin-producing cells have freed eight patients with a
severe form of diabetes from insulin injections.

Two to 14 months after being transplanted in a simple procedure
resembling a transfusion at the University of Alberta in Edmonton, the
cells are still working in all eight patients, half of whom were treated
almost a year ago.

The patients, who had Type 1 diabetes, in which the body produces little
or no insulin, no longer have any symptoms of the disease.  Although
they no longer need insulin to control their blood sugar, they now must
take other drugs to prevent rejection of the transplants.  So far, the
researchers report that the only side effect from the drugs has been
mild mouth sores, which healed.

The transplanted cells, isolated from the pancreas, were harvested from
deceased organ donors.  The goal of the treatment is to provide an
easier and safer alternative to transplanting the entire pancreas, a
major operation that is not commonly done.

"This is something people have wanted for a long time," said Dr. Judith
Fradkin, acting director of the division of diabetes, endocrinology and
metabolic diseases at the National Institutes of Health in Bethesda,
Md.  Noting that the procedure worked in eight out of eight patients,
Dr. Fradkin said, "If, when it's done in a larger number of patients,
you get anything like that success rate, it's a quantum leap."

Dr. Bernard Hering, director of the islet transplant program at the
University of Minnesota, said, "This shows that cell transplants can
reverse diabetes.  Here is something that can really work and can
transform a patient's life."

The Juvenile Diabetes Foundation, a nonprofit group that supports
research, called the work "a very significant step forward in curing
Type 1 diabetes."  Type 1 is sometimes referred to as juvenile diabetes.

The diabetes foundation and the health institutes will help pay for a
study to test the new procedure within a few months at eight transplant
centers in North America and Europe.  Each center will treat four
patients.  The American sites have not yet been named.

Researchers have been trying cell transplants for diabetes for more than
20 years, but most failed, or worked only briefly.  The success in eight
consecutive patients in Edmonton has been attributed to several factors,
like the use of a new combination of drugs to prevent rejection, and the
transplantation of many more pancreas cells than in the past.

The pancreas cells are transplanted into the patient's liver, where they
lodge in tiny blood vessels and begin doing their normal work of
monitoring and regulating blood glucose levels by secreting insulin and
another hormone, glucagon.

"They can now control glucose within a very tight range, as in a normal
individual," said Dr. Ray Rajotte, director of the pancreatic cell
research group at Edmonton.

To perform the transplant, doctors insert a catheter into the patient's
abdomen and snake it into the portal vein, which carries blood into the
liver.  The patient needs only a local anesthetic to numb the skin. 
About a teaspoonful of cells are injected through the catheter, and they
spray out and disperse through the liver.  The entire procedure can take
as little as 20 minutes.  Patients undergo it twice, with a few weeks
between transplants, to get enough of the insulin-secreting cells.

Dr. A.  M.  James Shapiro, part of the 44-member Canadian research team,
presented the research last week at medical meetings in Chicago and
Washington.  It will be published in The New England Journal of
Medicine, and an editor, Dr. Robert Utiger, said the study would be
posted within about two weeks on the journal's Web site, before it
appeared in print.  The journal's editors reserve this "early release"
policy for papers with especially important implications for patients.

The patients in the Canadian study were 29 to 53 years old.  All had
severe Type 1 diabetes that was poorly controlled by insulin shots. 
About a million Americans have the disease, which usually develops early
in life.  Most need several insulin shots a day.

An additional 15 million are thought to have Type 2 diabetes, in which
the body may make insulin, but cannot use it properly.  Type 2 tends to
come on later in life, and patients may or may not need insulin shots.

Together, the two forms of diabetes cause nearly 200,000 deaths a year
in America, and even with treatment they are a leading cause of
blindness, kidney failure and amputations.

Dr. Fradkin said that if the Canadian findings were confirmed by other
studies, cell transplants would be used first for Type 1 patients.  But
eventually, she said, they might also be given to some Type 2 patients. 
For now, Dr. Shapiro recommends the procedure only for severe Type 1

If the results are confirmed, it will create an unprecedented demand for
donor organs, Dr. Fradkin said.  The procedure devised in Edmonton
required two donor pancreases for every patient treated in order to
provide enough of the insulin-producing cells.  It costs $100,000.

Other research groups, like those at the University of Minnesota and the
University of Miami, are experimenting with techniques they hope will
allow them to use one pancreas per patient.  Still other scientists are
trying to find ways to grow pancreatic cells in culture.

There is great interest in cell transplants because many doctors feel
that transplanting the entire pancreas is too big an operation to be an
acceptable treatment for diabetes, even though the disease has
devastating complications and the surgical success rate matches that of
other organ transplants.

"It's a tender issue," said Dr. Paul Robertson, scientific director of
the Pacific Northwest Research Institute.  "There generally has not been
as much acceptance as there has been of heart, liver and kidney
transplants.  Physicians who don't do it say diabetes is not a
life-threatening disease."

That attitude angers some doctors and many patients, but, nonetheless,
pancreas transplants are not often performed.  Dr. Robertson estimated
that doctors did 1,200 transplants a year worldwide, with perhaps half
of them in the U.S. The vast majority are done only in people who also
need kidney transplants because of renal failure brought on by
diabetes.  In those cases, many doctors feel the pancreas operation can
be justified because the kidney failure demonstrates that the diabetes
is out of control, and because the patient will already be on
immune-suppressing drugs to prevent rejection of the kidney.

"But patients say, 'Do I have to get kidney failure before I can get a
pancreas?'  " Dr. Robertson said.

The earliest work on cell transplants was published in 1972, by Dr. Paul
Lacey, of Washington University in St. Louis, who showed in rats that
the procedure could cure diabetes.  Dr. Lacey transplanted the
pancreatic tissue known as islets of Langerhans, which makes up only 3
percent of the pancreas but contains all the insulin-producing cells,
called beta cells.

"Everybody thought, this is how we'll cure diabetes," Dr. Robertson
said.  But when researchers tried the procedure in people, it usually
failed.  Occasionally, the islets would function for a few weeks,
sometimes longer.  Doctors could not explain it.

But during the 1990's, they began to suspect that standard
anti-rejection drugs like steroids and cyclosporine might be damaging
the islets, because the islets sat in the liver, where those drugs
become most highly concentrated.

"There were plenty of hints in the medical literature" that the drugs
needed to be changed, Dr. Robertson said.  "But Edmonton gets the
credit.  They went ahead and did it."

Instead of steroids and cyclosporine, the Edmonton team used a
combination of three other antirejection drugs, tacrolimus, sirolimus
and daclimuzab.

But Dr. Rajotte said the drugs alone could not account for the group's
success.  He said it helped that the patients did not have kidney
failure and therefore were in an earlier stage of the disease than were
those in other studies.  In addition, he said, the new work was based on
30 years of research on how to isolate healthy insulin-making cells from
the rest of the pancreas.
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