The eyes have it: unlocking transplant tolerance in diabetes patients

Early experiments suggest that insulin-producing cells transplanted in the eye can function long-term without immune suppression

Finger prick blood test

New research suggests using the eye as a transplant site may be key to preventing the rejection of insulin-producing donor cells in diabetes patients.

The study, which was published in Diabetologia, found that islets transplanted in the eye could survive and function without long-term immune suppression.

Researchers hope that the discovery could lead to tolerance in peripheral transplant sites.

Islet transplantation is used to restore natural insulin production in people with type 1 diabetes.

However, at present diabetes patients require long-term immunosuppression to prevent the rejection of donor cells, which can result in serious side effects.

In a trial where diabetes patients received islet transplantation either in the kidney or the eye, both groups displayed islet survival for more than 300 days without immune suppression.

A second islet transplant into the kidney across all patients resulted in a 70% islet survival rate for more than 400 days in those who initially received a transplant in the eye, compared to a 30% survival rate in patients whose first transplant was in the kidney.

Dr Per-Olof Berggren, from the Diabetes Research Institute at the University of Miami School of Medicine, said: “This approach may help to positively impact the success of islet transplantation for future treatment of diabetes.”