We interviewed Dr James Pearson, a Type 1 Diabetes Grand Challenge researcher, who is investigating ways to prevent the immune system attack in type 1 diabetes. His research could help hold off the autoimmune attack on insulin-producing beta cells, which could delay or stop type 1 diabetes development altogether.
January 9, 2026
I have an uncle who was diagnosed with type 1 diabetes, and when I was a small child, I grew up watching him inject insulin and seeing the sort of pressures that came with managing the condition. That experience sparked all these questions about why someone develops type 1 diabetes when the rest of the family doesn’t. That interest stuck with me through university, and I knew that if I was going to do research, it had to be in type 1 diabetes — to help people living with the condition, with the hope that one day they can live an insulin-injection-free life.
That’s a big question! Our mice develop spontaneous type 1 diabetes, similar to humans. We’re testing a therapy that might delay or prevent that development. IL-2 is essentially a nutrient that helps regulatory T cells (“T-regs”) — our immune system’s natural bodyguards — function better. These cells help stop inflammatory T cells from damaging insulin-producing cells, but in type 1 diabetes, they don’t work very well.
By giving IL-2, we’re boosting the T cell’s ability to protect insulin-producing cells. We then monitor how effective that is — for example, how many mice develop diabetes after treatment. What’s fascinating is that timing makes a huge difference. If we give the therapy in the morning, about 20% of mice still develop type 1 diabetes. However, if we give it in the evening, the mice have complete protection against developing type 1 diabetes.
The difference between mice and humans’ body clocks is roughly 12 hours, because mice are nocturnal. So, if evening treatment works best in mice, it likely means morning treatment would work best in humans.
Different therapies might have different optimal times, depending on what part of the immune system they target — but the key takeaway is that timing matters. That’s what we’re now exploring in our Grand Challenge project: comparing morning and evening blood samples from people with type 1 diabetes to see how cells behave naturally, and then how they respond to IL-2 treatment in the lab.
Right now, we’re analysing samples from people with type 1 diabetes to see how their cells differ between morning and evening. This gives us information not just about T-regs but also about T cells in general, which could help other therapies too.
If we can show that timing truly makes a difference, we’d like to run a clinical trial where everyone receives IL-2 treatment — but some get it in the morning and some in the evening. We’d then compare the outcomes.
Because we’re doing a morning and evening study, my hours are quite long. I get up early, go into the lab, and get everything ready for when the first participant arrives. We greet them, ask about when they last ate or injected insulin, check eligibility, and make sure they’re okay to have a blood sample taken.
My research nurses, Shinto and Alex, then assist the participants. They provide a sample about half an hour after arrival, and it takes about two hours to process that and extract the immune cells.
After that, I spend the rest of my day analysing data from previous participants. By around 4 p.m., I start preparing for the evening sample. What’s lovely is that, unlike most studies where you see participants once, we see them twice in the same day — so we can ask how their day went, what they did in Cardiff, and build rapport. That’s really helped with retention and willingness to take part in future studies.
It would have to be the work we’ve done with people living with type 1 diabetes. Over the last year, we launched a group of young people, the Cardiff Diabetes Innovation Committee, who are co-creating and co-developing research that matters to them. This work has been supported by Breakthrough T1D, particularly Maddie Bonser and Alex Wild.
It’s been amazing to build relationships, bring researchers to meet them, and help them shape events that raise awareness of type 1 research. Seeing their enthusiasm and the sense of community has definitely been the highlight of my career.
Research doesn’t always go smoothly — experiments fail, results take time — but I remind myself why I’m doing it. I think of my uncle, or the people I meet at Discovery Days who are so engaged and hopeful. It’s also about responsibility: using the funds that people raise wisely to deliver research that will truly make a difference. That keeps me going.
Definitely. Historically, research has often been a one-way process — researchers take information but don’t always give feedback. We’re trying to change that by keeping participants updated after studies finish, even just with a short email to say we’ve reached a milestone. It’s simple, but it matters.
As someone with family affected by type 1 diabetes, I know there are both great and difficult moments. But you’re all doing an incredible job. Your participation, fundraising, and engagement make everything we do possible. We’re so grateful — and if anyone wants to get involved in future studies, we’d love to work with you.
