Diabetes in mice reversed with single injection of cultured cells

In a remarkable piece of research, scientists have managed to reverse diabetes in mice using a single injection of cultured cells which were able to produce the missing insulin which causes the disease.

They took immature cells from each animal's pancreas where insulin is normally produced, and nurtured the cells in a laboratory at the University of Florida. When injected just under the skin the cells began to function like normal insulin producing cells, known as islets of Langerhans.

"This is very exciting because the cells can be placed very simply into an individual in an area with no need for a complicated surgical procedure," said Dr Ammon B. Peck of the university's College of Medicine.

The work is described by Dr Peck and colleagues today in the journal, Nature Medicine.

Diabetes occurs when the body's immune system attacks and destroys the islets of Langerhans, leaving the person unable to produce insulin which regulates how sugar in the blood is used and stored.

People with the disease must take daily injections of insulin to keep their blood sugar levels under control. They can become comatose and die if blood sugar levels go too high or too low. In the long term it can cause side-effects including blindness, stroke and kidney failure.

The findings open the possibility of one day permanently reversing insulin-dependent diabetes. There are 80,000 people registered with the Irish Diabetic Association, including those taking insulin and those who control the disease with tablets.

The researchers used stem cells from the pancreas, immature cells which have yet to specialise and grow into one specific cell type. When cultured, they grew into insulin-producing cells and when injected they began controlling sugar levels and releasing insulin like normal pancreatic cells.

Equally encouraging, the new cells were not attacked by the immune system, unlike the original pancreatic cells in these mice, and continued working throughout the three-month study period. "This indicates there is some mechanism, something about growing them from stem cells in culture, that tricks the autoimmune response, at least for some time," Dr Peck said.

There were "still a number of hurdles" to be overcome before the procedure could be attempted and tested in humans, he said.