Scientists make first step towards treatment of type 1 diabetes using animal transplants

People with type 1 diabetes could one day be treated using transplanted cells from animals following pioneering research by scientists in the US.
For the first time, researchers at Northwestern University in Illinois were able to successfully transplant islets – clusters of cells in the pancreas that include insulin-producing beta cells – from rats into mice without the need for drugs to suppress the immune system.
Using a new technique, the team were able to persuade the immune systems of mice to recognise transplanted rat islets as their own and not attack (reject) them as foreign cells. In addition, this was done without the long-term use of immunosuppressive drugs, which often come with serious long-term side effects.
They scientists explained that a major problem in interspecies transplant (xenotransplantation) is controlling antibody-producing B cells . After receiving the rats’ islet cells, the immune systems of the mice initially started producing antibodies, causing rejection.
To counter this, the investigators gave the mice B-cell depleting antibodies at the same time as injecting the rat islets. This prevented the transplanted cells from being attacked when the B-cells naturally retuned after the transplant.
The mice were monitored for 300 days, and during that time the transplanted islet cells continued producing insulin.
Study co-senior author, Stephen Miller, said the research marks the “first step” towards animal-to-human transplant of islets without immunosuppressive medications .
The ultimate aim, he said, is to find a way to successfully transplant pig islets into humans as previous studies have shown that pig islets produce insulin that controls blood sugar levels in humans.
The hope is that by using islets from other species, it would help tackle the serious shortage of islet cells from deceased donors for patients with hard-to-control type 1 diabetes. Current waiting lists for transplants would be cut, which in turn would help reduce the number of patients suffering serious damage to their kidneys, eyes, nerves and heart while they wait for a donor.
The groundbreaking study is published in the journal Diabetes.