Dr Ruairi Robertson is a Postdoctoral Research Fellow at Queen Mary University of London conducting research on the role of the gut microbiome in child growth and undernutrition. Dr Robertson was also recently awarded a Marie Curie Individual Fellowship to study the early-life gut microbiome on infection susceptibility. Dr Robertson is involved in a number of human studies in sub-Saharan Africa including HOPE-SAM (Health Outcomes, Pathogenesis and Epidemiology of Severe Acute Malnutrition) and SHINE (Sanitation, Hygiene, Infant Nutrition Efficacy), which he talks about within this interview. We caught up with Dr Ruairi Robertson to find out more about his career, research and projects in Africa.


Ruairi Robertson

1. Can you tell us about your career path, and your journey to becoming a Postdoctoral Research Fellow at Queen Mary University of London?

I wasn’t too sure what I wanted to do when I was finishing school. I enjoyed Biology, but also subjects like Business Studies and French. I was rightly advised by various people to study what I enjoyed. I enjoyed food, so I studied Human Nutrition! I did this at University College Dublin. It was a great course as it provided us with the foundations in basic sciences (microbiology, biochemistry, physics) whilst specializing in nutritional science in later years of the course. I also had the opportunity to spend a whole year working in a lab in Tufts University in Boston, gaining experience in nutrigenomics research (the link between diet and genes). I was similarly confused as to what I wanted to do next at the end of my undergraduate degree, but I ended up beginning a PhD in the APC Microbiome Institute in University College Cork and Teagasc Food Research Centre in Ireland. I was lucky to be doing this just as the gut microbiome field was gaining a lot of attention and so it was an exciting time to be doing my PhD in that area. I conducted lots of studies in cells and mice examining how dietary fats influence the early-life gut microbiome. During the final year of my PhD I was awarded a Fulbright Scholarship to conduct a year of my research in Harvard University and Massachusetts General Hospital. This was a fantastic experience to spend time in one of the best Universities in the world. During this time, I began thinking about my next steps. Although much of my PhD research was focussed on the outcomes of overnutrition, I had always had an interest in child undernutrition and had previously spent a couple of months in Madagascar volunteering on a malnutrition screening project. So I decided to try and apply my new skills in gut microbiome research to undernutrition and began contacting various Professors around the world who were conducting child undernutrition studies. I stumbled across Prof. Andy Prendergast in Queen Mary University of London who was starting up lots of exciting mother-infant studies in Zimbabwe. He was extremely enthusiastic about the potential impact of the gut microbiome on child growth and so with his help, I wrote a fellowship proposal to the Wellcome Trust and was awarded it in 2017. I’ve been working on these projects ever since! 


2. What led to your interest in child growth and development, and in particular its relation to the gut microbiome?

During my 4 years of studying human nutrition in my undergraduate, about 90% of the focus was on overnutrition. I began to learn the statistics about child undernutrition – 1 in 5 children around the world are stunted, 50 million are wasted and much of this burden isn’t improved by current nutritional interventions – and became interested in the science behind it. I was lucky enough to gain lots of experience in international development programmes during University which included working on a child malnutrition screening project in Madagascar for a couple of months. Then during my PhD, I began to learn about the emerging evidence of the role of the gut microbiome in early life on things like asthma, allergies and even childhood obesity. If it could play a role in these disorders, why not in undernutrition?


3. The first 1000 days of life, from conception until around two years of age, is an important phase of a child’s development. You recently published a paper on the relationship between the first 1000 days of life, the gut microbiome and child development. Can you share with us the relationship between the gut microbiome and child development?

The period of the first 1000 days has been studied widely in the context of child undernutrition, as it is thought that this is a critical period that defines the trajectories of child growth until adulthood. Research has shown that there are a number of critical developmental pathways being trained and matured during this period helping to define these growth trajectories, including maturation of the immune system, production of growth hormones and metabolism of nutrients. However, little research has examined the influence of the gut microbiome on these growth-defining pathways. The gut microbiome also tends to mature during the first 1000 days. After birth and a few months of breast-feeding, the diversity of the gut microbiome expands rapidly. By ~2 year of age, or the end of the first 1000 days, the gut microbiome stops maturing and looks like that of an adult. Therefore, the gut microbiome has its own first 1000 days, which we hypothesize is an important window that defines growth throughout later childhood. This probably happens through many different pathways, for example the gut microbiome is responsible for metabolising various nutrients in early life, which may be important for growth. It also interacts with the endocrine system to mediate the production of particular hormones such as IGF-1 which are important for child growth. There are many other potential pathways by which gut microbes affect child growth and we are trying to tease them apart one by one!


4. Within this paper, you also delve into the gut microbiome and undernutrition in children. Can you give us an insight into the relationship between the two?

As discussed above, we hypothesize that the gut microbiome plays a role in a lot of the important metabolic, immune and hormonal pathways that are important for child growth. Therefore, if the gut microbiome is disturbed in some way, say through inadequate nutrition or a poor sanitary environment, this may impair its ability to control some of these important growth pathways. Interesting evidence has shown this in child obesity, whereby antibiotic exposure during this critical early life period can have long-term effects on the developing gut microbiome which ultimately leads to child weight gain. It is still not quite clear why this occurs, but it may be because the microbiome that remains after antibiotics is more efficient at extracting energy from food. There is less evidence in child undernutrition but similar processes may occur in the opposite manner to lead to poor growth, especially in settings where nutrition is inadequate.


5. Is there any evidence of microbiota-therapeutic interventions that may improve the gut microbiome of undernourished children?

Yes! Most of this has come from excellent work from Prof. Jeff Gordon’s lab in Washington University. They studied many different foods and their ability to support the development of the early-life gut microbiome in children in Bangladesh and designed a nutritional supplement to test in children who were acutely malnourished. They have recently shown that this nutritional intervention that specifically targets the gut microbiome is more effective for improving growth in children with acute malnutrition than traditional nutritional therapies. This shows that we need to begin considering feeding the gut microbiome of the child as well as the child themselves when thinking about combatting undernutrition.


6. Following on from the previous questions, your current research focuses on whether certain gut microbial taxa or pathways are associated with child growth, development and undernutrition. To understand this, you are involved in two projects in Africa: the HOPE-SAM (Health Outcomes, Pathogenesis and Epidemiology of Severe Acute Malnutrition) and SHINE (Sanitation, Hygiene, Infant Nutrition Efficacy) studies. Can you share with us what the background and aims of these projects are?

The SHINE study was a randomized intervention of improved WASH (water, sanitation and hygiene), improved infant nutrition or a combination, to examine whether these interventions could improve child stunting, the most common form of undernutrition, in >5000 mother-infant pairs. As part of the study, we are examining whether the gut microbiomes of the mothers and children are associated with child growth or are affected by the study interventions.

The HOPE-SAM study was an observational study of 745 children with complicated severe acute malnutrition who were being treated in hospital and 192 healthy controls. We followed up the children with malnutrition at a number of time points up to a year after they were discharged from hospital to examine the drivers of nutritional recovery and death. As part of this study, I am examining whether the gut microbiome is associated with their nutritional recovery and how it differs to healthily growing children.


7. Can you share any findings from these two projects thus far and whether there are any further plans for these studies?

In the SHINE study, the WASH intervention, which included building improved latrines, providing hand-washing stations and chlorinated water, had no effect on child growth, whilst the nutritional intervention reduced stunting by about 20%. We are now examining whether the gut microbiome of the mothers or infants in this study is associated with child growth. We have recently found that the composition of the mother’s gut microbiome predicts birthweight and neonatal growth in the infant suggesting that maternal interventions targeting the gut microbiome during pregnancy may improve fetal growth. We are now studying the effect on the infant gut microbiome.

In the HOPE-SAM study, ~20% of the children died either in hospital during treatment or in the year during follow-up. As expected, we have found that the gut microbiome of children during treatment for severe acute malnutrition is very different to healthy children and is composed of lots of pathogenic organisms. However, this tends to recover during follow-up. Intriguingly, we have found that children with oedematous malnutrition, a particular type of malnutrition traditionally called kwashiorkor, have very different gut microbiomes to those with classical non-oedematous malnutrition.


8. Earlier this year you were awarded the EU-funded Marie Curie Individual Fellowship to study the early-life gut microbiome on infection susceptibility. Firstly, congratulations! Can you give us an insight into what you will be getting up to?


Thank you! This project will allow me to explore a little more deeply how the gut microbiome may contribute to the immune system’s ability to fight off intestinal infections. We know surprisingly little about this. A diverse gut microbiome can prevent pathogens from colonizing the gut by competing for space and nutrients, but little is known about how the gut microbiome may train the immune system in early life to fight off infection. I will study the effect of the gut microbiome in early life on a particular type of intestinal immune cell and examine what happens if the gut microbiome is disrupted during this period, for example through antibiotics. I will then test whether these changes to the gut microbiome and intestinal immune cells in this important window in early life, affects the risk of a serious infection later in life. This can all be brought back to the context of undernutrition as well. Children in low-resource settings carry lots of pathogens which may impair their growth and lead to diarrheal infections, which are responsible for millions of child deaths. By examining how the gut microbiome contributes to these processes, it may be possible to design new nutritional or other treatments to prevent infections and help children in these settings to grow, survive and thrive.


9. Between your fellowships and personal projects in science communications – what do you enjoy doing in your spare time?


I play various sports, both competitively and socially, including football, tag rugby and gaelic football. I’ve recently got into cycling and enjoy sight-seeing around the city or going out into the countryside and coast on the bike, which usually ends with a rewarding meal in the pub!


10. If you could give those who are thinking of applying for a fellowship one piece of advice, what would it be?

Think of the 3 P’s: Person, Place, Project. Most fellowships are scored in some way around these three criteria, so it is important to explain the strengths of each of them in a clear way.

Person: Why are you the right person to do this research? What skills have you gained, what experience do you have managing projects, why are you better than others?

Place: Why is this particular University/Institute/Setting the best place to do your research? Funders want people to conduct their research in the best settings possible. This does not necessarily mean the world’s top ranked University, however it has to be the best place for you to conduct your individual research project and the best place to support your development as an independent scientist. Think about the research facilities, department expertise and what support your Institute provides to early career researchers.


Project: Why is this research project important? This is surprisingly often neglected by people writing fellowships/grants. Reviewers/grant panels won’t always be as familiar with your field as you are. It is important to explain the world-class nature of your potential research and its’ novelty, but also why it is important to the world. What potential impact could it have?

Posted: 14/09/2021