Dr. James Crawford, chairman of the UF pathology department and editor-in-chief of Laboratory Investigation, said, These promising results just add to the growing evidence that adult stem cells may be a critically important source of treatment options for patients with debilitating diseases in which normal tissues are destroyed.

UF researchers hope that adult stem cells will lead to a diabetes treatment that does not involve the danger of tissue rejection, a major obstacle to current type 1 diabetes therapies using transplanted islets of Langerhans, Petersen said. Additional research is needed to explore whether the cell clusters mimic natural islets too effectively for their own good - the diabetic mice used in the current study were genetically altered and had no immune system, so their bodies could not mistake the cell clusters for islets and attack them.

As much as I would like to be able to go to a clinical trial tomorrow, we ™re not ready, Petersen said.

The study began with removal of bone marrow cells from the long leg bones of about 30 rats. The stem cells were then separated from other cells using a chemical bath, collected and cultured in a solution containing either large or small amounts of glucose, a type of sugar.

When the cell clusters formed, researchers confirmed production of the hormones using seven tests. In the study ™s second phase they implanted about 150 cell clusters each into nine diabetic mice, under a membrane that surrounds each kidney. Within two to three days blood glucose in the mice began to reach normal levels. After another two weeks, the clusters were removed from six of the mice and those animals ™ blood glucose levels increased, suggesting the cell clusters were responsible for the normalizing effect, Petersen said.

Mice that retained the cell clusters maintained fairly normal blood glucose levels until the study ended after 90 days, and the animals appeared capable of producing the insulin indefinitely, Petersen said. Two control groups totaling 13 diabetic mice did not receive cell cluster implants and continued to have abnormally high blood glucose levels.

Oh designed the study, inspired by previous UF research showing that rat liver stem cells could be coaxed into producing insulin. Both Oh and Petersen are named in a patent application for the technology, filed in October.