Our research has resulted in changes to islet cell transplant procedures in the UK. Eligible people with type 1 diabetes were previously given two transplants of donor pancreas cells within the space of a year and these findings revealed that a shorter time between transplants improved the success of this treatment. Now, national guidance has been changed to make sure everyone who has an islet transplant and then requires a second transplant, receives a top up within three months of their first.
In islet transplants, clusters of cells (called islets) are taken from a donor pancreas and given to a person with type 1 diabetes. The transplanted cells can help people to make some of their own insulin again for a time, helping to keep their blood sugar levels stable and avoid hypos. For this group of people, islet transplants can be life changing and life-saving, although they aren’t a permanent solution.
In 2008, the UK launched the world’s first government-funded islet transplant programme, making this pioneering treatment available on the NHS for people with type 1 diabetes who have severe hypos and hypo unawareness. This was thanks to the work of the UK Islet Transplant Consortium, funded by Diabetes UK. The initiative brought together leading researchers to ensure islet transplants would become available in the UK to those who could benefit the most.
Now, our researchers have looked back at everyone who had a successful islet transplant in the UK since 2008. They examined factors, such as the amount of islets transplanted, the number of transplants received (typically 1 or 2 within the space of a year) and the timings of these transplants, to find out which helped to improve the effectiveness of the treatment.
Professor Shareen Forbes, at the University of Edinburgh, and her team looked at the outcomes of 84 people with type 1 diabetes up to 10 years after they’d had the treatment.
The study, published in the American Journal of Transplantation, found that one year later people who had two transplants had more surviving islets and were able to produce more of their own insulin compared to people who’d had a single transplant. However, by six years after the transplant the benefits were similar for both groups.
A shorter time interval between the two transplants helped to improve the effectiveness of the transplants. In those getting their second transplant within 3 months, the total amount of insulin people injected or pumped each day was reduced by 75% one year after their transplant. This compared to a 48% reduction in daily insulin dose for those who had a longer gap (averaging six months) between their transplants.
Changing islet transplant guidance
The findings from this study have directly led to a revision of the UK Pancreas Allocation Scheme, so that everyone who is eligible for an islet cell transplant should now receive a second transplant if required within three months of their first.
We’ve backed research into islet transplants since the very beginning, investing around £2.3 million in the last 10 years alone. Along with improving the effectiveness of islet transplants today, we're continuing to support research to make them even better, and more accessible, in the future. Read more about our scientists’ latest findings.
And because donor islets are scarce – limiting the number of people with type 1 diabetes who could benefit – we’re also investing in research to grow new insulin-producing cells in the lab. Scientists hope this will give us a way of creating an unlimited supply of cells that could be transplanted into people with type 1 diabetes in the future.