Preventive therapy for diabetes

Scientists claim to have found a preventative therapy for Type 1 diabetes, which is an autoimmune condition where the body attacks its own insulin producing cells.

An international team believes that by making the patient's killer immune cells tolerate the insulin-producing cells, it would normally attack and destroy, prior to onset of the condition.

Type I diabetes is found usually in youth. People with Type 1 diabetes must maintain an insulin-monitoring and insulin-injecting regimen for the rest of their lives.

The scientists, led by Eliana Mario and Dr Shane Grey, from the Garvan Institute of Medical Research in Sydney, have demonstrated how a particular molecule may be used in future as a preventative therapy.

The body's immune cells, or white blood cells, include B cells and T cells. B cells make antibodies and present 'antigens' to T cells, allowing them to recognise, and kill, invaders.

In previously published studies about Type 1 diabetes, the team showed that groups of B cells migrate to the pancreas and pancreatic lymph nodes presenting specific insulin antigen to T cells. In other words, B cells go to the disease site and tell T cells to kill the cells that produce insulin. "Taking that work further, our current study looks at different ways of subduing B cells, and how that affects development of the disease," Dr Grey said.

Working with mice that spontaneously develop Type 1 diabetes, Eliana Mario found that if she blocked BAFF (a hormone that controls survival of B cells) prior to onset, none of the mice developed diabetes.

"This is a remarkable finding, as other B cell depletion methods tested elsewhere have just delayed or reduced disease incidence," Mario said. When B cells were depleted, the regulators of the immune system (a subclass of T cells known as T regulatory cells) rose in numbers.

By removing B cells from the picture for a while, it appears you allow T regulatory cells to function as they should, subduing killer T cells and somehow making them tolerant of the insulin producing cells. The findings of the study have been published in the 'Diabetes' journal.