It’s time to explore the immune system’s clock

Science Lives: Dr Annie Curtis of the RCSI’s strategic academic recruitment programme

Annie, you are interested in what makes our body clocks tick. Can you explain?
"Each of us is a collection of clocks, we have a timing mechanism in every cell that helps us to anticipate what we need to do over a 24-hour cycle. Our clock systems are affected by light and dark and by eating. These allow our cells to schedule activities such as digesting the food we eat, and being alert and active during the day and sleeping at night.

With funding from Science Foundation Ireland and the Irish Research Council, my lab at the Royal College of Surgeons in Ireland (RCSI) looks at clock mechanisms in the immune system. This system is alert to bugs and viruses during the day and it's emerging that at night the immune system seems to build its memory of what it "saw" during the day.

Why are you looking at clocks in macrophages?
We love macrophages and dendritic cells in our lab. They are front-line cells of the immune system. They travel around in the blood and if there is an infection or an injury, the macrophages look to kill off bugs and start the process of clearing out the dead and infected cells. We want to see what macrophages do at different times of the day and night, and what controls that.

And what have you found?
We just had a big paper in the journal Proceedings of the National Academy of Sciences which I am delighted about. We were able to show how the clock in the macrophage controls an important molecule of the immune system called interleukin-1B. It's really interesting because interleukin-1B is often dysregulated in chronic diseases such as diabetes, rheumatoid arthritis and heart disease – and people who do shift work and who most likely have a disrupted body clock, tend to have a higher risk of developing these diseases.


What keeps you ticking along in research?
Well, the research itself is not for the faint-hearted – we look at what happens at all times of day and night, so sometimes experiments need to be done at 2am. I am not the one in the lab doing this work, that is down to my fantastic team of PhD and post-doctoral researchers. But what keeps us all motivated is getting the results. When a member of the team gets a cracking result and you know you are on to something, the clouds around a particular question clear and you say "this is it", that is a pure rush.

Have you changed your own clock habits through being a clock researcher?
Completely. When I was younger I didn't think about my body clock much at all, but now I am really conscious of it. I am an early bird, so I tend to be in bed at 10pm and I try to sleep until 6am. I also try not to eat after 8pm, because eating sends a signal to your peripheral body clocks to be active but at that time your brain clock is telling you to prepare for sleep. Now, of course, occasionally I'll enjoy the curry chips in the small hours on a night out but at least I am aware of the issues with that now.

What do you do to get a break?
We have young kids, so outside of work and family I don't have much spare time. But when I can, I get to the beach for a run and I love to do yoga and to read. And when we go for a night out, we love the cinema.

Claire O'Connell

Claire O'Connell

Claire O'Connell is a contributor to The Irish Times who writes about health, science and innovation