Intelligent bacteria for detecting disease

Research teams from Inserm and CNRS Montpellier, in association with Montpellier Regional University Hospital and Stanford University, have transformed bacteria into "secret agents"

These agents can give warning of a disease based solely on the presence of characteristic molecules in the urine or blood.

To perform this feat, the researchers inserted the equivalent of a computer programme into the DNA of the bacterial cells. The bacteria thus programmed detect the abnormal presence of glucose in the urine of diabetic patients.

This work, published in the journal Science Translational Medicine, is the first step in the use of programmable cells for medical diagnosis.

Bacteria have a bad reputation, and are often considered to be our enemies, causing many diseases such as tuberculosis or cholera. However, they can also be allies, as witnessed by the growing numbers of research studies on our bacterial flora, or microbiota, which plays a key role in the working of the body. Since the advent of biotechnology, researchers have modified bacteria to produce therapeutic drugs or antibiotics. In this novel study, they have actually become a diagnostic tool.

Living cells are real nano-machines that can detect and process many signals and respond to them. They are therefore obvious candidates for the development of powerful new diagnostic tests. However, they have to be provided with the appropriate "programme" for them to successfully accomplish the required tasks.