The need to make islet replacement successful as a viable cure
for patients with juvenile diabetes (also known as Type 1 diabetes)
received a boost last month with the launch of a new Juvenile Diabetes
Research Foundation (JDRF) Center for Islet Transplantation at Emory.
The center is being funded with a three-year, $4.1 million grant
and will address an important issue facing islet transplantation:
rejection of donor islets by the patients immune system. Although
islet transplantation from donor pancreases can restore normal insulin
production in patients with Type 1 diabetes, several problems exist
with current immunosuppressive protocols. The Emory center will
ambitiously explore various initiatives toward the goal of insulin
independence for these patients, without long-term immunosuppression.
Researchers will explore various interrelated approaches to reduce
the requirements for immunosuppressive drugs. They also are investigating
the use of less toxic drugs than current therapies and testing whether
donor islets transplanted from animals can be protected in a delicate
membrane from the bodys immune response.
Collin Weber, director of the new JDRF center, has had a distinguished
career that includes 30 years of investigations in the field of
diabetes research. Webers co-director is Christian Larsen,
who will lead the clinical islet transplantation program. Larsen,
director of the Emory Transplant Center, is recognized internationally
for his work in devising strategies to achieve transplantation tolerance.
Significant progress in islet transplantation was made in
the Edmonton Protocol in Alberta, Canada, in patients with very
severe, life-threatening problems with glucose control, Weber
said. However we realize that wide-scale application of islet
transplantation using conventional immunosuppressants is not feasible
because of long-term side effects. Our goal here is ambitious and
exciting and, if successful, will improve the effectiveness of transplants
and create a larger source of donated islets.
Two of the centers projects will focus on using a steroid-free
approach with a new class of compounds called co-stimulation
blockers. One of these compounds has already shown promise
to protect kidney transplants from attack by the immune system.
In one project, investigators will carry out a clinical trial of
human islet transplantation using the most promising drug. In the
second related project, researchers will perform preclinical studies
and examine tolerance induction to islet grafts using
the co-stimulation blockade approach in nonhuman primates.
Other projects will focus on the use of microencapsulated pig islets
to address the problem of limited availability of human pancreatic
tissue. In these studies, investigators will examine the ability
of pig islets encapsulated in a protective membrane to correct diabetes
in laboratory mice. The researchers will work to optimize the design
of the protective membrane to prevent immune attack of the pig islets
while maintaining islet function. The technique may also be applied
to the transplantation of human islets.
The Emory Transplant Center is one of the most comprehensive transplant
centers in the South-east, featuring programs in heart, lung, liver,
kidney and kidney-pancreas transplants and fostering cutting-edge
basic, translational and clinical research to improve the effectiveness
of transplantation.
JDRF is the worlds leading nonprofit, nongovernmental funder
of diabetes research. Since its inception in 1970, JDRF has provided
more than $500 million to diabetes research worldwide.
The launch of this new center at Emory underscores JDRFs
determination to keep research on a fast track to find a cure for
a disease affects more than 16 million Americans, said Charles
Queenan, chair of research for JDRF. JDRF has been in the
forefront worldwide with islet transplantation as one of its priorities.
The possibilities are both tantalizing and frustrating, but the
research must now focus on conquering autoimmunity and tolerance
issues.
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