Lister Fellow Chris Stewart recently received a UK Blavatnik Award for his work on the microbiome in infants and its role in preventing illness. The awards recognise exceptional young scientists in Life Sciences, Chemical Sciences, and Physical Sciences and Engineering. In each category, one Blavatnik Laureate receives £100,000 in unrestricted funding, while two finalists each receive £30,000.
To mark his Life Sciences Blavatnik Laureate achievement, we sat down with Chris to find out more about his current research, his future plans, and how it felt to don a tuxedo and give a speech on microbiomes at a glittering awards ceremony.
Q: The last time we spoke to you was shortly after you received the 2023 WH Pierce Prize. What’s been happening since then?
A: It has been a great year. I feel incredibly fortunate that people think to nominate me for these prizes. I think there might be a bit of a Matthew effect, where one success breeds more success, but it gives me a lot of belief in myself that colleagues thought they should nominate me for an award completely out of the blue, and that alone is a tremendous honour. One of my nominators for the Blavatnik award was Del Besra, who’s the president of the Microbiology Society and also a former Lister Fellow. Impostor syndrome never goes away, but, remembering that I’ve received nominations and awards like this indicates that I’m obviously doing something right.
I also feel these awards I’ve received have been given to me as an individual, but it’s always for a team effort. I’m not sure science has ever been done by individuals in the way that the awards process suggests and team science is more critical than ever to meaningfully advance complex biological challenges.
[T]hese awards I’ve received have been given to me as an individual, but it’s always for a team effort. I’m not sure science has ever been done by individuals in the way that the awards process suggests and team science is more critical than ever to meaningfully advance complex biological challenges.
Q: The Blavatnik Awards ceremony is a black tie event. Was it fun to attend?
A: It was just the most amazing evening – wine, dinner, champagne, the classic awards ceremony stuff. My wife and I both went and I got to meet some fantastic and lovely people. The attendees were eclectic and ranged from leading academics and numerous Nobel Prize Laureates, to billionaires and politicians – then there’s little old me from the northeast of England with a basic tuxedo trying to blend in. But I felt that I made a pretty good account of myself overall. The Laureates have to give a 10 minute talk and mine went well. It’s all scripted and teleprompted, which I’ve never experienced before, and it does take the pressure off a little.
The black tie event is only one side of the story though. In the evening there’s the formal ceremony and medal presentation, then the following day a public event is held online and at the Royal College of Medicine in London. The Laureates and finalists give talks and interested members of the public can attend for free. A lot of families who are homeschooling join in as part of their children’s education. We also had pupils from nearby schools who asked some amazing questions. It was a lovely day with very good attendance. I don’t know how many people joined online, but I know my dad was among them!
Q: The Blavatnik awards recognised your work on preventing necrotising enterocolitis (NEC) and developing your gut organoid model. Your research also explores how the oligosaccharides in breast milk help build beneficial bacteria populations. How does that work?
There has been a lot of research in this area in the last few years. A series of publications, including my 2018 paper, showed that breast milk is the most important driver of the infant gut microbiome. When a baby stops receiving breast milk, their microbiome changes quite drastically and there is a huge turnover in the microbial community. In particular, a type of microbe called Bifidobacterium rapidly declines.
So the next question we and others began asking is what is in breast milk that causes the microbiome to be so radically different? And what component of milk feeds these Bifidobacterium populations? We are almost certain now that human milk oligosaccharides (HMOs) are the biggest drivers of the bacterial community that dominates the infant gut. They are primarily – and possibly exclusively – a prebiotic, meaning that they are an ideal food source for these beneficial bacterial strains.
These HMOs are among the most abundant components in milk, even more so than a macronutrient like protein which the baby needs in order to grow. Evolution is not a wasteful process, so if a mother uses a large amount of her energy to produce HMOs, it’s likely for a good reason. It really does lend support to the idea that a microbe using these sugars will be beneficial somehow. Our work suggests that they produce metabolites that are very anti-inflammatory, which could be a good thing for infants suffering from inflammatory-mediated diseases.
Evolution is not a wasteful process, so if a mother uses a large amount of her energy to produce [Human Milk Oligosaccharides], it’s likely for a good reason. It really does lend support to the idea that a microbe using these sugars will be beneficial somehow.
However like most things in biology, it’s never quite that simple. The very latest findings suggest that these food sources can also be co-opted by other bacteria, albeit to a lesser extent. We recently published a preprint exploring how a bacterium called Clostridium can also use the HMOs. Some strains of Clostridium are associated with negative effects, like gas gangrene, so it’s possible that it could be pathogenic to the baby, but the biology is very nuanced. Our data suggests Clostridium that lacks a toxin found in pathogenic strains could actually very beneficial for infants. There is lots to be discovered and we’re deep into the science at the moment.
Q: Do you work closely with clinical teams in Newcastle?
We couldn’t do any of our work without the clinical team. They are the critical component – I just have the pleasure in coming to do some fun science. I am based at the university in Newcastle, but it’s only a four-minute walk from my lab to the neonatal intensive care unit (NICU). It’s technically in a separate building, but it’s all connected internally. I go down one flight of stairs, and I’m there in the NICU with all the fantastic neonatologists.
We are a tertiary centre, meaning that we have a large catchment area and the most poorly babies from that region all come to our hospital for their care and surgery. So from a research perspective, that gives us an inflated number of interesting samples to study.
When I started my PhD in Newcastle at Northumbria University, I was working with a neonatologist, now a professor and a good friend, called Janet Berrington. She had a vision for our microbial ecology research and we started collecting and freezing samples from the neonatal babies’ nappies, which would otherwise just be thrown away. By 2013 we had put a couple of thousand samples in this biobank, and today we put well in excess of 100,000 samples through it, including milk, urine and blood. It’s an incredible resource for someone like me, and that is absolutely credit to the clinical team who do it on a goodwill basis.
We don’t have a large amount of funding to support the biobank infrastructure, but Professor Janet Berrington remains absolutely committed to keep driving this forward and providing the detailed data on each baby and samples to my team. If we were to go back 15 years and write a grant proposal to do this, we would probably be asking for millions, and we’ve done it on £15,000 of funding from the local charity Tiny Lives, so it’s an incredible achievement. All that effort is down to clinicians who want to improve the outcomes of their patients and recognise the value of working with and supporting researchers.
