Islet cell transplantation
Islets
Islets are groups of cells in the pancreas which contain the insulin-producing beta cells. These cells make insulin as needed in order to keep blood glucose levels just right.
Islets and diabetes
In people with Type 1 diabetes the beta cells are destroyed so they must take insulin by injection to remain healthy. This means having to estimate how much insulin they will need and for some people it is very difficult to achieve stable blood glucose levels.
Islet transplantation
A small number of people with Type 1 diabetes can benefit from islet transplantation. This is a procedure in which an individual’s destroyed islet cells are replaced using cells harvested from donor pancreases.
How islet cell transplants work
Typically, a transplant patient will receive islets from up to three donated pancreases. The transplanted cells produce insulin which stabilises the diabetes and reduces the amount of insulin that needs to be administered. In some cases the transplanted cells may produce enough insulin to allow a person to come off insulin completely.
How islet cell transplants came to the UK
In 2000, details of highly successful improvements to the islet transplantation procedure were published by researchers in Edmonton, Canada. These were quickly adopted worldwide. In the UK, Diabetes UK set up the Islet Cell Consortium, which brought together nine islet research centres from around the country to ensure the technique was available here for the benefit of people with diabetes. With the help of our members and supporters, Diabetes UK raised the money needed to pay for the first ten islet transplantations to be done in the UK according to the “Edmonton Protocol”. Since then, Diabetes UK has secured funding to transplant another five patients. Nine of these fifteen transplants have now been successfully performed at three centres of excellence in Oxford and London.
Still an experimental therapy
Islet cell transplantation remains an experimental therapy and is not yet sufficiently well advanced to guarantee insulin independence and freedom from diabetes. Moreover, the drugs required to prevent rejection of the transplant can have serious side effects.
This means the procedure is currently only suitable for those people who have extreme problems controlling their diabetes, experience innumerable hypos with little or no warning which can be life threatening, and as a consequence have drastically reduced quality of life.
Successes
To date, one person – Richard Lane, who underwent a transplant at King’s College in London under the care of Professor Stephanie Amiel and her team – was able to come off insulin.
All the other transplanted patients in the trial have benefited from being able to lower their insulin doses, remove hypoglycaemia, and improve their blood glucose control. While not ‘free of insulin’, just having a minimum number of functioning islet cells in the body can help to stabilise blood glucose levels and stop the sudden lows that all these individuals had previously suffered from.
One of the most important results is that they have been able to return to a normal lifestyle after having suffered major disruption due to hypoglycaemia.
One recently transplanted patient is our first ‘single donor’ success. Under the care of Dr Martin Press and his team at the Royal Free in London, she received just one transplant as opposed to the more usual three. She now has a normal blood glucose level without insulin, but is being kept on a tiny precautionary dose to help keep her new islets healthy.