Posted: March 2022Explainers
The human immune system works every minute of every day to keep the body healthy – through constant monitoring, and by tracking and destroying pathogens, such as disease-causing bacteria and viruses.
But the immune system is infinitely complex, and tricky to control. Cancer cells, for instance, have developed sneaky ways to evade it. And in autoimmune diseases like type 1 diabetes or rheumatoid arthritis, the immune system goes ‘rogue’ and attacks the body’s own healthy cells.
The idea of harnessing the immune system as a form of medicine is not new. Vaccination is the best example – the principle of which may have been first applied as long as two millennia ago in China.
But it has taken decades of scientific effort worldwide in more recent times to understand the intricacies of human immunity, and how we might employ these to cure complex and chronic diseases.
Immunotherapy is now a burgeoning and broad treatment umbrella. In cancer medicine, therapies such as checkpoint inhibitors or CAR –T-cells can boost the immune system, enabling it to work against cancer cells. On the other hand, in autoimmune conditions like type 1 diabetes, immunotherapies are being used to stop the immune system destroying cells the body needs.
“Type 1 diabetes occurs when the immune system mistakenly begins destroying a person’s own beta cells in the pancreas, as if they were a foreign invader,” explains Professor Helen Thomas, Head of Islet Biology at St Vincent’s Institute of Medical Research (SVI).
“Beta cells produce insulin, which regulates the body’s use of glucose. When a large number of beta cells have been killed, insulin production plummets, blood glucose levels rise and the symptoms of type 1 diabetes soon follow. Once destroyed, beta cells are sadly lost to the body forever, and affected people require replacement insulin from then on.”
But what if we could slow or stop the action of the immune system?
“SVI has played an important role in international efforts to build knowledge of the auto-immune mechanisms that cause type 1 diabetes, and to test drugs that might inhibit this,” says Professor Tom Kay, Director of SVI and an internationally recognised expert in type 1 diabetes.
“Through clinical trials for those who have been recently diagnosed, like SVI’s current BANDIT trial, we are beginning to translate this understanding into potential treatments.”
“The ultimate goal for immunotherapies in type 1 diabetes is three-fold. First, to develop screening tools for people at risk of developing the disease, so we can intervene early to delay or completely stop the immune system attack before a critical mass of beta cells is lost.
Second, to identify and test treatments for those recently diagnosed – as in our BANDIT trial – that might reduce the auto-immune response. The more beta cells that can be preserved, the less reliant the person will be on replacement insulin.”
“Thirdly, there is the potential to replace beta cells in people already living with type 1 diabetes, combined with treatments to stop immune system attack on those new cells.”
“Working closely with clinicians and hospitals nationwide and connecting with colleagues across the globe, we are beginning to see how immunotherapy could radically change the treatment of type 1 diabetes in years to come.”