In people with type 1 diabetes, the body doesn’t produce enough insulin to effectively regulate levels of blood sugar. In healthy individuals, insulin is produced by beta cells in the pancreas. For many years, scientists have been exploring potential ways to replace these beta cells and restore insulin production.
One option – transplanting cells from donors – has met with limited success because of a lack of donor cells and because recipients face the possibility of rejecting the transplant. At the Wake Forest Institute for Regenerative Medicine, researchers are working on two projects with the goal of restoring the body’s natural capacity to produce insulin:
Engineering pancreatic beta cells: This project involves a new type of stem cell – discovered by institute scientists – that is derived from amniotic fluid. These cells can give rise to many of the specialized cell types found in the human body. Scientists are working to coax these cells to differentiate into pancreatic insulin-producing cells. The ultimate goal is to produce cells that are able to regulate insulin levels based on the amount of glucose the cells are exposed to. The team's work shows early promise -- with success controlling diabetes in mice for short periods of time. Ongoing work focuses on how to extend this effect by understanding more about how the cells function in the pancreas.
The Bioartificial Pancreas: This project addresses the major obstacles to the transplantation of insulin-producing cells: lack of donor cells and issues with rejection. The project involves using donor cells that are "encapsulated” with a thin membrane that allows oxygen and nutrients to enter the capsule, but prevent issues that would cause the patient to reject the cells. With this approach, the replacement cells could come from animals or could be engineered from stem cells. One major obstacle – being able to efficiently encapsulate the large number of cells needed for therapy – has been solved with advances in engineering. Current challenges include ensuring that the cells will have an adequate oxygen supply to survive and function after implantation.
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