New Source of Insulin-Producing Cells Developed

In a step towards making a larger number of insulin-producing cells available for transplant in-patients with diabetes, researchers at Joslin Diabetes Center in Boston have discovered a way in the laboratory to encourage human pancreas cells that do not normally produce insulin to become insulin-producing cells.

This latest discovery suggests that pancreatic duct cells – cells which would normally be discarded in the process of preparing human islet cells for transplant – can be encouraged through use of a readily available commercial culturing material to become insulin-producing cells that the scientists have dubbed "cultivated human islet buds (CHIBs)."

Researchers believe that identifying a plentiful source of insulin-producing cells is a major barrier to creating an effective means of transplants to treat type 1 diabetes. Currently the supply of islet cells available from donors is much too small to help all the estimated 800,000 Americans who have type 1 diabetes. Only about 3,000 pancreases become available for transplant annually, and patients usually need islet cells from two pancreases for each transplant.

If a plentiful source of insulin-producing cells can be developed scientists might even one day be willing to try transplants in some of the estimated 15 million Americans with type 2 diabetes.

Other Encouraging Reports

A new protocol developed by researchers at the University of Alberta in Edmonton might make it possible to successfully transplant human islet cells in type 1 patients and bring blood sugars to a normal level for an extended period to time. Previous islet transplants have had very limited success, for a variety of reasons. The body’s immune system wants to attack the transplanted cells because the cells are perceived as foreign invaders. This is the classic challenge faced by any transplanted organ. In someone with type 1 diabetes, however, the body’s immune system also attacks the transplanted islets because of the immune malfunction that caused diabetes initially.

The Edmonton Protocol, in contrast, has resulted in seven type 1 diabetes patients remaining diabetes-free for up to 14 months. In most previous islet transplants, patients might maintain normal blood sugars for a few days or a few weeks, at most. The Edmonton Protocol uses a different combination of anti-rejection medications and does not use steroids to prevent rejection of the transplanted islets, which scientist suspect may be key to its greater success.