Insulin-producing tissue was transplanted between unrelated mice by teaching the immune system to accept foreign tissue in what researchers say could be a step toward curing diabetes.
In a study published in the Proceedings of the National Academy of Sciences, scientists at the University of Massachusetts Medical Center in Worcester, Mass., said they demonstrated in mice a technique of transplanting insulin-producing pancreatic islets without the use of anti-rejection drugs.Dr. Aldo A. Rossini, senior author in the study, said the transplant technique involves shots of white blood cells, made from the donor mice, and injections of a substance called anti-CD40L. Together, these shots train the immune system of the receiving mouse to tolerate the transplanted pancreatic islets.
In the study, Rossini and his team used mice that had been turned into diabetics by disabling the pancreatic cells that produce insulin. The mice were then divided into two groups, some receiving the shots of the white blood cells and the anti-CD40L.
For those getting the shots, 37 of 40 mice showed no sign of rejecting the transplants. The cells made insulin and arrested the diabetes.
A control group of mice that received transplanted cells, but without the white blood cells or antibody shots, quickly rejected the transplants. Their immune systems killed the transplanted cells - and the mice received none of the insulin.
A study showed the technique works so well that islets from rats were successfully transplanted into mice, Rossini said. The diabetes in the mice was stopped by the transplanted rat cells, he said.
Diabetes is caused when islet cells in the pancreas stop producing insulin.