Type 1 diabetes mellitus usually develops when people are young. The insulin secreting cells in the pancreas are destroyed or simply stop making insulin, so the blood sugar levels go out of control which can be very serious and can even be fatal. Fortunately people with diabetes can lead relatively normal lives as a result of regular, self administered doses of insulin.

Although insulin injections work well enough, people affected by diabetes have to monitor their food intake and their blood sugar levels and give themselves injections of insulin to avoid problems. Stem cell therapy offers the hope that they can be given working pancreas cells again, restoring insulin production and so blood sugar control.

Scientists have succeeded in persuading some mouse embryonic stem cells to form a group of cells that looked just like insulin-producing tissue and worked like it too. Some of these cells were transplanted into mice with diabetes and to their delight the team saw an increase in the blood levels of insulin and improved control of blood sugar. It will be many years before these early results are transformed into a human treatment for diabetes, but the signs are hopeful.