Gene therapy can prevent the onset of diabetes in mice prone to developing the disease.

The technique's success could lead to new knowledge about the development of Type 1 diabetes and ways to treat it, said senior investigator Paul Robbins of the University of Pittsburgh School of Medicine. The findings were presented yesterday in Baltimore at the annual meeting of the American Society of Gene Therapy.

"We actually deliver therapeutic genes in an animal model of diabetes and it completely blocks diabetes," he said. "It's a fairly dramatic effect, so we're excited about it."

In the project, researchers led by Khaleel Rehman Khaja attached a gene that makes interleukin-4, a cytokine than inhibits inflammation, to a harmless virus called adeno-associated virus. It was designed to be active only in pancreatic islet cells that make insulin.

The gene therapy was administered to diabetes-prone mice, and the IL-4 appeared to interfere with the immune cell attack on insulin-producing cells.

"It's protecting them from destruction," Dr. Robbins explained. But diabetes development accelerated in mice that got a gene for another cytokine, interleukin-10, researchers found.

With the technique, "we can now deliver a variety of genes and see if they would be therapeutic or, alternatively, see if those factors actually enhance the rate of onset of diabetes," he said.

The mouse model also makes it possible to see the impact of interventions at different stages of the disease. It's a great technique, Dr. Robbins said, but he cautioned that "it's not clear if we can use the same approach in humans."

The project was one of several from Pitt being discussed at the gene therapy conference, which ends tomorrow.

"There really is a lot of progress being made in a number of different areas," Dr. Robbins said. "There's a lot of very positive things coming out at this meeting."