A new imaging method has been developed that could be used to develop more effective antibiotic treatments.
During bacterial infections like tuberculosis, bacteria enters human cells, which poses a challenge for treatment as antibiotics must reach and enter all infected cells in order to be effective.
Researchers at the Francis Crick Institute and the University of Western Australia have developed a new imaging method to see where in infected tissues and in cells an antibiotic given to treat tuberculosis reaches the bacteria. The scientists are continuing to work on the method, adapting it for other types of antibiotic and to image multiple antibiotics at the same time.
The team – whose findings were published in PLoS Biology – believes that the method could reduce the length of treatment that is needed, which in turn could reduce the risk of antibiotic resistance developing.
Max Gutierrez, author and group leader of the host-pathogen interactions in tuberculosis laboratory at the Crick, said: “In the case of tuberculosis, people need to be treated with at least three different antibiotics over six months. We don’t yet fully understand why this extended treatment is needed.
“We hope that being able to more clearly see where antibiotics are going will help us better understand this process and find ways to improve it.”
To develop the imaging method, called CLEIMiT, the researchers analysed lung tissue from mice infected with tuberculosis and treated them with the antibiotic bedaquiline.
They combined a variety of imaging methods, including confocal laser scanning microscopy, 3D fluorescence microscopy, electron microscopy and nanoscale secondary ion mass spectrometry to develop their new approach.
Using this method, they found that bedaquiline had not reached all infected cells in the lung tissue and had not entered all infected areas within infected cells.
They also found this antibiotic collecting in macrophages and in polymorphonuclear cells, both types of immune cells.
Tony Fearns, author and senior laboratory research scientist, said: “Our approach could be used to help develop new antibiotics or to reassess current antibiotics to judge how effectively they reach their targets.
“The more we learn about how drugs behave in the body, for example where they collect, the better we will be able to treat bacterial diseases like tuberculosis.”