Bacterial viruses alleviated the symptoms of E. coli poisoning in mice and rabbits, despite antibiotic treatment often worsening the condition. This result was achieved by inserting the CRISPR-Cas12 tool into the viruses, which cut out the genomic region responsible for toxin production. Although this approach still requires human trials and the determination of a safe dose, it could become a targeted method for combating various antibiotic-resistant bacteria, not just E. coli. The study was published in the journal Science Translational Medicine.

Scientists targeted strains of Escherichia coli that produce Shiga toxins. Infection with these strains is particularly dangerous for children, where it can cause bloody diarrhea and even kidney failure. Moreover, antibiotics can trigger the activity of the gene responsible for Shiga toxin production. Therefore, the scientists used the gene-editing tool CRISPR-Cas12 to completely remove this gene from the bacterial genome.

Since the approach worked in cell culture, the researchers then developed methods for delivering it to bacteria in the bodies of patients. For this, they used natural enemies of bacteria—bacteriophages, which are capable of penetrating bacterial cells and integrating into their genome. Using these viruses, the scientists significantly reduced the number of E. coli cells in the bodies of infected mice, as well as mitigated the symptoms of poisoning, reversed the toxic effects, and promoted the restoration of the intestinal epithelium in infected newborn rabbits.