April 23 (HealthDay News) -- Transplanted pancreatic precursor cells encapsulated in polytetrafluorethylene (PTFE) are protected from the immune system and able to mature into functional beta cells that control blood sugar levels, U.S. researchers report.

In experiments with mice, they also found that using precursor cells, rather than more committed beta cells, increases the likelihood of transplant success. These findings could lead to a new approach to treating type 1 diabetes, said scientists at the Burnham Institute for Medical Research and the University of California, San Diego, School of Medicine.

The study was published online in the journal Transplantation.

"The results exceeded our expectations," Pamela Itkin-Ansari, an assistant adjunct professor at the UC San Diego School of Medicine and Burnham, said in a school news release.

"We thought that T-cells, although unable to penetrate the (PTFE) device, would cluster around it. But we found no evidence of an active immune response, suggesting that the cells in the device were invisible to the immune system," she explained.

In people with type 1 diabetes, the immune system attacks and kills insulin-producing beta cells in the pancreas. Transplantation of beta cells to treat diabetes requires the long-term use of immunosuppressive drugs, which carries health risks.

Being able to use a protective device to transplant beta cells could reduce the need to use immunosuppressive drugs, the study authors said.

SOURCE: University of California, San Diego, Health Sciences, news release, April 9, 2009