The team at Boston Children’s hospital witnessed that all mice subjects were cured of the disease short-term after a blood stem cell transfusion and one third of them were then able to maintain normal blood sugar levels for the duration of their lives.
Although it is not known how long-term this reversal will be or how it will work in humans.
When people (or animals) have type one diabetes, the immune system’s autoreactive T-cells attack insulin-producing islet cells located in the pancreas, meaning they can’t produce sufficient insulin.
Previous studies have found that people who have the disease are deficient in a proteins, called PD-L1, which are responsible for being a ‘checkpoint molecule’ that curbs this over aggressive autoimmune reaction.
As a result the team wanted to see what would happen if they could transfuse pre-treated cells, via gene therapy or pre-treatment with small molecules, to produce more of the PD-L1 protein and counteract this deficiency.
Paolo Fiorina, senior investigator on the study, said: “There’s really a reshaping of the immune system when you inject these cells.”
This had an immediate effect of reversing hyperglycemia in the mouse model.
“The beauty of this approach is the virtual lack of any adverse effects, since it would use the patients’ own cells,” said Fiorina.
Further study will now be needed to determine how long the effects of the cell therapy last and how often the treatment would need to be given.
Currently, the number of people diagnosed with diabetes in the UK is estimated to be 3.5 million. This represents 6% of the UK population or 1 in every 16 people, according to Diabetes UK.
This isn’t the first study to try and use immunotherapies for type one diabetes, but previous attempts have failed in part because the therapies have not targeted diabetes specifically.
For example, autologous bone-marrow transplant, which infuses patients with their own blood stem cells to reboot their immune system, has helped some patients, but not all.