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• Position: Type 1 Diabetes - Islet cell and stem cell treatment

Type 1 diabetes afflicts as many as 3,000,000 Americans. In those who have the disease, the pancreas produces little or no insulin, a hormone that helps the body use or store blood glucose from food. Most patients require regular insulin injections, but some need surgical intervention--either a pancreas transplant or an islet cell transplant, in which insulin-producing islet cells from a donor pancreas are infused into the liver.

However, the number of available donor pancreases is limited. To address this hurdle, Klearchos Papas, professor in the Department of Surgery at the University of Arizona, Tucson, is studying the efficacy of islet cells from sources other than the human pancreas--including beta cells derived from human stem cells, and islet cells from pigs.

The trouble is, those who receive an islet cell transplant must take immunosuppressant drugs for the rest of their life, which can be very taxing on the body. For that reason, transplants are performed only on patients who absolutely need them and rarely are done in children. This especially is problematic, since the onset of type 1 diabetes most often occurs during childhood or young adulthood.

As an alternative to implanting cells directly into the liver, the medical community has explored implanting patients with cells contained in a special immunoisolation device, which would eliminate the need for anti-rejection drugs and potentially allow for the safe use of islet cells from alternate sources.

Implantable just beneath the skin, the postage-stamp-size device has semipermeable membranes designed to protect the cells from attack by the immune system while still allowing the insulin produced by the cells to pass through the device to the body.

The challenge with the device is the number of islet cells it can accommodate...