Although the work is not yet ready for human patients, Seung Kim, MD, PhD, the lead author and assistant professor of developmental biology at the Stanford University School of Medicine, said it could lead to new ways of transplanting insulin-producing cells into people with diabetes, eventually providing a cure for the disease.

In past work, Kim and members of his lab enticed mouse embryonic stem cells to transform into insulin-producing cells. When transplanted into diabetic mice, these cells effectively made up for the lost insulin-producing cells in the pancreas, called islet cells, and treated the diabetes. However, embryonic stem cells are difficult to work with in the lab and most existing human embryonic stem cell lines are contaminated and can't be transplanted into humans.

Kim thought that human neural stem cells may be one way to sidestep the more problematic embryonic stem cells. The study shows that his intuition was correct.

"When you look at islets cells you realize that they resemble neurons," Kim said. Like neurons, islet cells respond to external signals by changing their electrical properties and releasing packages of proteins. In the case of islets, that protein is insulin.

What's more, some neurons in mice and humans take the first steps toward producing insulin. In insects such as fruit flies, the cells that produce insulin and regulate blood sugar are, in fact, neurons. Taken together, this evidence suggested to Kim that neural stem cells may be able to produce insulin.

Despite Kim's informed hunch, the fact that it worked is a bit surprising.

Until recently, people had though that stem cells taken from the brain would only be able to transform into b
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Contact: Amy Adams
amyadams@stanford.edu
650-723-3900
Stanford University Medical Center
25-Apr-2005