A new technology could enable doctors to use microorganisms to diagnose and treat disease from inside the gut microbiome in future, according to a recent study.
Scientists genetically engineered bacteria to emit and respond to light signals, so they could communicate with them via a smartphone app.
If the same treatment proves safe and effective in humans, it could help combat a plethora of diseases, including those that are currently difficult to treat.
The process involved three components: bacteria, tech and pigs. Led by senior author Hanjie Wang from Tianjin University in China, the scientists modified Escherichia coli bacteria to respond to specific chemical and light signals.
They developed a swallowable capsule that could be controlled via Bluetooth and communicate with these light-responsive bacteria, and infected three pigs with colitis, a form of inflammatory bowel disease where sections of the gut can become swollen.
The experiment began. The scientists put some of the engineered E. coli into the inflamed guts of the pigs and made each animal swallow a capsule.
Nitrate is a chemical compound that the body produces when the gut is inflamed and acts as a marker of active colitis. When the modified E. coli came into contact with nitrate, they lit up.
The smart capsules could detect this light signal and inform the scientists of the presence of E. coli via Bluetooth.
Using a smartphone app, the scientists were then able to instruct the capsule to start flashing its LED light – which, in turn, triggered the E. coli to secrete anti-inflammatory antibodies to help combat the colitis.
In this way, the scientists were able to communicate with the bacteria and deliver treatment exactly where it was needed.
“This is a truly exciting technological development,” Dr Lindsey Edwards, senior lecturer in microbiology at King’s College London, told BBC Science Focus. Edwards was not involved in this research.
“Technologies like this, which allow precise, real-time interaction with gut bacteria, could be part of a new generation of therapies,” she continued.
“We urgently need new tools that help us better understand, monitor and work with microbes to help fight infections, alongside harnessing the true potential of the microbiome to restore or improve health.”
There is currently no cure for colitis, and treatment options are limited. Edwards said future technology like this “could open up new avenues” – not just for treating inflammatory bowel diseases, but also other conditions linked to gut health, such as type 2 diabetes, heart disease and chronic fatigue.
However, Dr Alexandre Almeida – from the Department of Veterinary Medicine at the University of Cambridge, who was not part of this study – told BBC Science Focus that this possibility remained a long way off.
“This is still an early-stage, proof-of-concept study,” he said. “The technology has only been tested in animals so far, and only for detecting one specific condition.
“Before it can be used in humans, further research will need to evaluate the general safety of this technology and answer some important questions – such as how these engineered microbes affect the natural balance of other bacteria living in the gut.”
Dr Nicholas Ilott, senior researcher at the Oxford Centre for Microbiome Studies, who did not take part in this research, told BBC Science Focus that this technology was “incredibly exciting” and would be “extremely useful” in future medicine.
Read more:
- Bacteria: The miracle microbes that could fix the planet
- 15 tips to boost your gut microbiome
- The human microbiome: Everything you need to know about the 39 trillion microbes that call our bodies home
About our experts
Dr Lindsey Edwards is a senior lecturer in microbiology at King's College London, UK. Her research interests are in mucosal barrier immunology, host-microbe interactions and subsequent priming of adaptive immune responses, as well as intestinal and liver diseases.
Dr Alexandre Almeida is the principal investigator and the MRC Career Development Fellow at the University of Cambridge's Department of Veterinary Medicine, UK. Throughout his career, he has specialised in the development and application of bioinformatics and genomic approaches to make biological discoveries relevant to human health.
Dr Nicholas Ilott is senior researcher and lead bioinformatician for the Oxford Centre for Microbiome Studies, in the Nuffield Department of Orthopaedics Rheumatology and Musculoskeletal Sciences, University of Oxford, UK. He specialises in host-microbe interactions in chronic liver and inflammatory bowel diseases.
