Type 1 diabetes happens when the body's immune system attacks and destroys insulin-producing beta cells in your pancreas. To prevent type 1, we need to stop the immune system going rogue in the first place, so that it doesn’t destroy beta cells. We can’t do this at the moment, but scientists are working on it.
The path to type 1 diabetes
Scientists are studying relatives of people with Type 1 diabetes, who have a higher risk of developing the condition themselves, to unpick the complex causes of type 1 diabetes and track the process leading to the destruction of beta cells.
And that includes our researcher Dr Kathleen Gillespie. She leads BOX: the longest running family study of type 1 diabetes in the world. Here’s Dr Gillespie explaining how this research is helping us to predict who will get type 1 diabetes, with the ultimate aim of being able to prevent it.
TrialNet is a global research network dedicated to preventing type 1 diabetes. They are also studying people with a family link to type 1 diabetes to try and pinpoint what happens in the immune system in the months and years before a diagnosis. They worked out that the immune attack goes through three different stages.
- Stage 1: you have at least two autoantibodies. Autoantibodies are molecules which tell us that the immune system has started attacking the beta cells in your pancreas. This is considered to be the start of type 1 diabetes because at this point your likelihood of developing the condition in the future is almost 100%.
- Stage 2: your blood glucose levels become higher than normal, as more beta cells are being destroyed. But you don’t yet have any symptoms and you don’t need to take insulin.
- Stage 3: the immune system has killed off so many beta cells that you’re no longer able to produce enough of your own insulin. Blood glucose levels become dangerously high and the symptoms of type 1 diabetes appear. This is known as the clinical onset of type 1 diabetes and is usually the point you’d get diagnosed.
Blocking the path
With a simple blood test, scientists can detect people who are at stage 1 or 2. Those people can then be invited to take part in clinical trials testing new treatments, called immunotherapies, which hope to halt the early stages of the immune attack and prevent a diagnosis.
These treatments work by reprogramming the immune system and you can find out more about immunotherapies on our spotlight page.
Until recently, no immunotherapy trials had successfully altered the progression of type 1 diabetes. But this all changed in 2019.
A team of TrialNet scientists showed that a drug, called Teplizumab, could delay the diagnosis of type 1 diabetes by an average of three years in people who were at ‘stage 2’.
There are still many questions, and we’re not talking about preventing the condition entirely yet. But this breakthrough shows us that the course of type 1 diabetes can be altered and provides real hope for other immunotherapy research.
Finding another path
Scientists are looking for ways to intervene even earlier – before any changes to the immune system take place.
Our genes can increase our chances of developing type 1 diabetes, so they can be a useful tool to spot who is at a higher risk.
Our research fellow, Dr Richard Oram, is developing a ‘risk calculator’ that uses information from genes linked to type 1 diabetes to find newborn babies who are at higher risk of developing the condition at some point in their lives.
Right now, risk scores like this could help to find people who could benefit from taking part in a prevention clinical trial. But potentially in the future – once there is a way of preventing type 1 diabetes – they could be used as a screening tool to identify children who would benefit from the treatment.
Scientists believe that our environment could play a part in causing the immune system to go rogue, and so it may hold the key to preventing type 1 diabetes.
Prevention trials have explored changes to our diets, including a baby milk formula that was free from insulin, a gluten-free diet in the first year of life, and an omega-3 fatty acid. But none of these were found to delay or prevent type 1 diabetes in children who had a higher genetic risk.
TEDDY is a major study hoping to identify new environmental factors which could contribute to the onset of type 1 diabetes, to help us work out how to prevent it. TEDDY scientists are following high risk children and are looking for differences in the environment between the children who develop type 1 diabetes and the children who don’t.
So far they haven’t found any strong links to environmental factors, but their work is far from over.
Another prevention strategy scientists are exploring is immune training. Rather than trying to intervene to stop an immune attack, scientists hope to make the immune system more tolerant so that an attack is never triggered in the first place.
This works in a way similar to treatments for peanut allergies, where giving young children tiny amounts of peanut can help their immune system learn to not react against it.
A group of scientists – called GPPAD – are working on this. They’re running a world-first trial, called PoINT. PoINT is finding out if giving oral insulin to babies who have a high genetic risk of type 1 diabetes could stop them from developing the condition in later life.
The trial launched in 2018 and will run for seven years. There’s a while to wait before we get any results, but if successful, this research could be a vital step towards preventing type 1 diabetes.
Scientists need you
You could play an important role in advancing type 1 prevention and immunotherapy research.