Researchers at ETH Zurich have developed a bacteriophage system to identify and treat bacterial bladder infections. Bacteriophages are viruses that infect bacteria, but these microorganisms have fallen out of favor as a treatment method for infection since antibiotics came along. Well, antibiotics are looking increasingly shaky as bacteria evolve to resist them, so researchers are returning to bacteriophages as a way to treat antibiotic-resistant infections. However, these Swiss-based researchers have turbo-charged bacteriophages by genetically modifying them so that they are more effective at killing bacteria, and also so they will express a bioluminescent signal in the presence of their target bacteria. This forms the basis for a diagnostic technology for bladder infections, whereby in just a few hours after administering the phages, the researchers can investigate a urine sample for a bioluminescent signal, and identify the infective bacteria.
Antibiotic resistance has complicated the treatment of many infections. This is true of bladder infections, in which clinicians are eager to administer antibiotics, but without knowing the identity of the infective bacterium they are essentially flying blind. Administer the wrong drug, and the infective bacteria will be largely unperturbed, setting the patient’s recovery back and potentially even fueling new forms of drug resistance.
Bacteriophages represent a completely different way to treat infections, with these viruses displaying a highly specific ability to target one type of bacterium, unlike antibiotics which usually demonstrate a much broader spectrum in their action. This bacteriophage specificity has utility, provided you know what the identity of the infective bacterium is, but what if it could help you to identify the bacterium in the first place?
This is the approach of these researchers, who have developed a dual diagnostic/anti-bacterial bacteriophage system that can both identify and kill three of the most common bacterial species involved in bladder infections: Escherichia coli, Klebsiella, and Enterococci. Several hours after being administered to patients with a suspected bladder infection, the researchers can collect a urine sample and then analyze it for the bioluminescent signal that the phages have been engineered to express when they encounter their target bacterial species.
The phages have also been engineered to kill the bacteria more effectively, and will release antibacterial proteins that can kill other bacteria in the bladder that are not so easily targeted otherwise. Â
Study in Nature Communications: Engineered reporter phages for detection of Escherichia coli, Enterococcus, and Klebsiella in urine
Via: ETH Zurich