Transplants from both embryonic and adult pigs could treat diabetes in rats with no need for immune suppression drugs, scientists have discovered.
In a step toward curing diabetes in humans, scientists at Washington University School of Medicine have alleviated the disease in rats using transplants from both embryonic and adult pigs.
Using a two-step approach, the researchers first transplanted a cluster of embryonic pig pancreatic cells into diabetic rats.
These cells grow to become the pancreas, which houses the islet cells that produce insulin.
The embryonic cells primed the rats' immune system to accept a second implant of islets from adult pigs several weeks later.
The new research - the first long-term, successful cross-species transplant of pig islets without immune suppression - raises the prospect that it may one day be possible to cure diabetes in humans using a similar strategy.
"While human islet transplants have cured diabetes in some people, there are so few donors that only a small percentage of patients get transplants," said senior author Marc Hammerman MD, the Chromalloy Professor of Renal Diseases in Medicine.
"Moreover, those who receive human islet transplants must take anti-rejection drugs for the rest of their lives, so essentially they are trading daily insulin shots for immune-suppression drugs, which carry their own risks. Our research paves the way for a new approach to treating diabetes, one that features a virtually unlimited supply of islets and no need for immune suppression.
"This is a major advance and a completely new way to employ pig islets for the treatment of diabetes.
"Adult pig islets provide a more concentrated source of insulin and are easier to obtain. We are hopeful their ability to effectively control blood sugar levels in rats without an immune suppression requirement will carry over to non-human primates and eventually to humans," he added.
The findings were published in the American Journal of Pathology.