Type 1 diabetes is the end result of an autoimmune response that destroys insulin-producing beta cells in the pancreas. The subsequent deficiency of insulin prevents the body’s cells from taking glucose from the bloodstream for use as an energy source. This, in turn, results in hyperglycaemia – a state of high glucose levels in the blood.
Long-term exposure to hyperglycaemia is life-threatening. It causes tissue damage, affecting blood vessels and nerves. Type 1 diabetes increases the risk of heart disease and stroke, and triggers blindness and kidney failure in adults.
Loss of insulin production requires treatment with insulin injections, but this rarely controls blood glucose adequately. While this issue can be overcome by transplanting pancreatic islet cells, the high cost, need for toxic immunosuppressive drugs and shortage of donor tissue limit the implementation of this treatment. A further setback is that few transplant recipients have achieved independence from insulin injections.
Therefore there is a need to generate renewable sources of insulin-producing cells. Alternative sources of beta cells, such as embryonic and adult stem cells, have been considered for this role.
Embryonic stem cells are self-renewing and have the capacity to generate all types of adult cells. Already, insulin-expressing cells have been generated from mouse...
