Media release

From: Springer Nature

Microbiology: App controls gut bacteria behaviour in pigs

A smartphone-controlled ingestible capsule that can control and allow for two-way communication with gut bacteria in pigs is reported in Nature Microbiology. The findings could lay the foundation for new diagnostic and treatment strategies for diseases, such as colitis.

Gastrointestinal microorganisms are known to impact health, but whether they can be controlled remains unclear. Bacteria, such as Escherichia coli, can be modified to deliver site-specific drugs inside animals. However, once they are inside an organism, it is difficult to communicate with them or control their behaviour.

Hanjie Wang and colleagues engineered E. coli to communicate with an ingestible smart capsule using light signals. The authors were able to observe and control this communication through a smartphone app that connects to the capsule via Bluetooth. As a proof of concept, Wang and coauthors used three pigs with induced colitis (inflammation of the colon) and colonised them with the engineered E. coli that emitted light upon detection of nitrate, a marker of colitis. The smart capsule, which features a custom-printed circuit board powered by three button batteries, was ingested by the pigs and detected this light signal and relayed it to the app. Through the app, the authors directed the capsule to emit light by flashing an LED. This turned on a light-sensitive genetic circuit in the E. coli, triggering the secretion of anti-inflammatory antibodies that alleviated colitis.

This technology could enhance the precision of microorganism-based diagnoses and therapies by improving control over the behaviour of engineered bacteria inside of a living organism. Further refinement of this system to support multiple rounds of communication and clinical testing could one day allow for its application in treating human diseases.