Combined treatment for Type 1 diabetes could stop immune system in its tracks
JDRF researchers in California and Italy have successfully used ‘gene therapy’ to reverse the immune attack behind Type 1 diabetes in mice.
Mice that received the treatment not only kept their remaining insulin-producing beta cells, but also stabilised their blood glucose levels without external insulin.
The researchers, led by Professor Maria Grazia Roncarolo, developed the treatment by combining two kinds of therapy that have shown promise for treating autoimmune conditions in the past. The first, gene therapy, saw them transfer part of a gene involved in insulin production into liver cells.
This spurred the mice’s immune systems into stopping any rogue immune cells that might try to kill off insulin-producing cells. As a result, no more of these rogue cells were able to infiltrate the pancreas, even up to 33 weeks after the therapy. In comparison, mice that did not receive gene therapy had lost 80 per cent of their insulin-producing cells after 33 weeks.
However, this part of the treatment did not reduce the number of immune cells present – it only maintained it. To allow the mice to restore their blood glucose levels, the researchers then used a single dose of a drug that can kill off immune cells. After this, 75 per cent of the mice had blood glucose levels that stayed low for many weeks without needing external insulin.
The drug, called a monoclonal antibody, is often used after organ transplants to stop the immune system rejecting the organ. But there are issues with using these drugs continuously, as the body needs its immune system to fight off illnesses. So the fact that the treatment only needed a single dose – thanks to the addition of the gene therapy – is very promising.
Rachel Connor, Head of Research Communication at JDRF in the UK, said: “Over the last few years our understanding of how the immune system works in health and in Type 1 diabetes has grown enormously. This innovative study has come up with a novel way of helping the immune system bring the attack on insulin producing beta cells under control, and even reverse it.
“Gene therapy treatments are beginning to be tested in people now, so despite a long research journey ahead, approaches like this one may one day be able to help people with Type 1 diabetes.”
The research was published in the journal Science Translational Medicine.