DRWF-funded researchers in the US make breakthrough in islet cell transplantation.
For decades immunologists have been trying to train the transplant recipient’s immune system to accept transplanted cells and organs without the long-term use of anti-rejection drugs.
However, researchers in the US have made a breakthrough that shows this is now possible following a DRWF-funded study.
An islet cell transplant is the only effective and remaining treatment option for people with type 1 diabetes unable to produce insulin with end-stage organ failure.
In a recently published report in Nature Communications, researchers at the University of Minnesota showed that it is now possible to maintain the long-term survival and function of pancreatic islet transplants despite complete discontinuation of all anti-rejection drugs on day 21 after the transplant.
To prevent transplant rejection, recipients must take medication long-term that suppresses the body’s immune system.
These immunosuppressive drugs are effective at preventing rejection over the short term; however, because anti-rejection drugs suppress all of the immune system non-specifically, people taking these drugs face the risk of serious infections and even cancer.
In addition, non-immunological side effects of immunosuppression, such as hypertension, kidney toxicity, diarrhoea, and diabetes can reduce the benefits of transplantation.
Proof that immune tolerance of transplants can be achieved was first demonstrated in studies reported by Peter Medawar in his Nobel Prize–winning Nature article more than 65 years ago. Yet, despite its immense significance, transplant tolerance has been achieved in only a very few patients.
This new study capitalises on the unique attributes of modified donor white blood cells, which were infused into transplant recipients one week before and one day after the transplant, thereby recapitulating nature’s formula for maintaining the body’s tolerance of its own tissues and organs. Without the need for long-term anti-rejection drugs, islet cell transplants could become the treatment option of choice, and possibly a cure, for many people with type 1 diabetes.
Bernhard Hering, MD, Professor and Vice Chair of Translational Medicine in the Department of Surgery at the University of Minnesota, who also holds the Jeffrey Dobbs and David Sutherland, MD, PhD, Chair in Diabetes Research and senior study author, said: “Our study is the first that reliably and safely induces lasting immune tolerance of transplants.
"The consistency with which we were able to induce and maintain tolerance to transplants makes us very hopeful that our findings can be confirmed for the benefit of patients in planned clinical trials in pancreatic islet and living-donor kidney transplantation - it would open an entirely new era in transplantation medicine.”