Guardians of the Gut

We are exhibiting ‘Guardians of the Gut’ at the Royal Society Summer Science Exhibition 2018 from Monday 2 July – Sunday 8 July in London. Guardians of the Gut has been funded by a Wellcome Trust Engagement Fellowship, a Microbiology Society Microbiology in Society Award 2018 and the Biotechnology and Biological Sciences Research Council, who provide strategic support to the Quadram Institute.

What are we doing?

We are fascinated about understanding how our resident gut microbes (i.e. the microbiota) impact our health, and we are particularly interested in what happens during early life. In our Royal Society Summer exhibit we explore the amazing variety of microbes that colonise the gut right from the start, from their initial ‘seeding’, and where we get them from (exploring natural vs. C-section birth), and how specific types, e.g. Bifidobacterium, our favourite bacteria(!), act as Guardians of the Gut. We discuss how microbes play a key role in healthy development; helping to digest components of our food (breast or formula milk), and also how these microbes ‘talk’ to our immune cells. As these bacteria are so important for our wellbeing, we also explore how disturbing these early life microbial communities through e.g. antibiotics, can have short- and long-term consequences, and may predispose us to chronic diseases such as Ulcerative Colitis. Finally, we showcase some of the approaches and therapies, we and others, are developing to promote healthy early life microbial ecosystems with the aim of maintaining health and treating disease.

Some facts and figures!

  1. 1. We are roughly half microbe, half human! There are approximately 1.5 X more microbial cells than our own human cells, and as many as 5000 microbial species.
  2. 2. The microbiome refers to all microbes including bacteria, viruses, archaea, eukaryotes, and fungi.
  3. 3. The generic material encoded in these microbes is 150X more genes than the human genome!
  4. 4. We are colonised by microbes both on and within our bodies, including skin, oral, and vaginal, but the gut is the most popular and diverse place to be!
  5. 5. Our knowledge of the microbiota has gone together with technology development, with DNA/RNA sequencing playing as big role in unlocking the black box of microbial complexity.
  6. 6. Microbes are seeded at birth – but some studies suggest there may be in utero exposure, but this is controversial so more research needs to take place to confirm these findings.
  7. 7. Birth mode impacts what types of microbes you get; C-section babies have more ‘skin-like’ microbes in the gut as these are often the first microbes they encounter, vs natural birth, where you get vertical transmission from mum to baby.
  8. 8. Early life diet has a massive impact in the composition of gut microbes. Breast milk contains dietary components, called human milk oligosaccharides that ‘feed’ specific bacteria, including Bifidobacterium. The baby can’t use these milk components directly, so they must be broken down by their microbes, which in turn produce beneficial compounds like vitamins.
  9. 9. Most of our immune programming happens in the early life window, and as such our resident gut bacteria play a massive role in shaping how our immune cells function. In fact, our gut is home to the majority of our immune cells, which means it’s a key microbe-immune interface.
  10. 10. The microbial ecosystem is very unstable during these first early phases, and as a result is much more susceptible to disturbances, such as occurs through antibiotics. Antibiotics are critical for fighting off nasty pathogens, but they also kill beneficial bacteria like Bifidobacterium, which may link to the fact that babies who gets lots of antibiotics when then are young have a higher risk of developing chronic gut and immune disorders, like Ulcerative Colitis and Asthma. Diet, e.g. formula rather than breast milk, and birth mode, C-section vs. natural birth, also correlates with ‘altered’ early life microbial community (and often reduced levels of Bif), which may also link to the fact that these factors are also linked to increased incidence of chronic inflammatory conditions.
  11. 11. Faecal microbiota transplant (FMT) represents a way to restore the microbiota ecosystem if it is disturbed; patients who have Clostridium difficile infection, and whom antibiotic treatment has been unsuccessful are now able to get FMT on the NHS. This treatment was so successful, 94% cure rate, that it was fast tracked onto The National Institute for Health and Care Excellence (NICE) guidelines.
  12. 12. Another route to rebalance our microbes is via administration of probiotics, defined by WHO as “live organisms which, when administered in adequate amounts, confer a health benefit on the host”. Traditionally, species and strains belonging to Lactobacillus and Bifidobacterium have been used, but other species are now being looked at. Groups, like our own, are working towards rational design of Bif therapies, with the aim to translating these therapies to improve maternal and infant health.

Some useful links for further information

Microbiome Policy Project

The Microbiome and Human Health POSTnote