Inflammatory bowel diseases like colitis or Crohn's disease are thought to impact around 7 million people, who have to be diagnosed before they can be treated. Will patients one day be able to swallow a pill that journeys through the gastrointestinal system, collecting information along the way to provide a diagnosis once the trip is complete? That vision is getting closer to reality with new research reported in Nature, which builds on work published in Science in 2018. Scientists have created a so-called smart pill that is safe to ingest, very small, and can assess biological molecules including hydrogen sulfide byproducts and nitric oxide, which can indicate the presence of harmful inflammation that is associated with bowel disease.
Diagnosing bowel disorders can be challenging and uncomfortable for patients, who typically have to undergo endoscopies or colonoscopies. But these tools cannot measure biomarkers in real time, especially because those biomarkers tend to be gone before current methods can detect them.
This smart pill aims to change that. It contains engineered, live bacteria, electronics, and a small battery. If the engineered bacteria detect a particular molecule of interest, light is generated. In the pill, the light is converted to a wireless signal, which can be trasnsmitted to a device like a computer or phone. This data can all be sent while the pill moves in the gut. This device has been successfully tested in a pig model.
The work showed that the smart pill can detect various levels of nitric oxide, which can help clinicians distinguish between normal and unhealthy guts. A pill that can provide real-time measurements is particularly useful because typical levels of nitric oxide can differ dramatically from one person to another.
"The inner workings of the human gut are still one of the final frontiers of science. Our new pill could unlock a wealth of information about the body's function, its relationship with the environment, and the impact of disease and therapeutic interventions," said senior study author Timothy Lu, an MIT associate professor.
In bowel disorders, flare ups often occur but can be very difficult to anticipate, which can make treating them very challenging. There are no reliable biomarkers that indicate the onset of a flare, so patients end up experiencing serious symptoms. This new device could help change how these diseases are managed.
This tool could open up new insights into the workings of the gut, many of which are still a mystery. "We still don't fully understand it because it's difficult to access and study. We lack the tools to explore it," said Maria Eugenia Inda, a Pew Postdoctoral Fellow at MIT. "Knowing more about the gut chemical environment could help us prevent disease by identifying factors that cause inflammation before the inflammation takes over."
It may also be possible to modify the smart pill so it can detect other molecules, and provide a convenient way to monitor health over time.