Klebsiella pneumoniae is a pathogen most commonly associated with nosocomial (hospital-acquired) infections leading to pneumonia, urinary tract, and soft tissue infections, as well as to more severe conditions such as septicemia, liver abscess, and sepsis, particularly for the hypervirulent strains. However, K. pneumoniae is also a gut colonizer and pathobiont. In fact, it has been associated with several gut-related diseases. Federici et al demonstrated that K. pneumoniae was significantly enriched in patients with inflammatory bowel disease (IBD), including both Crohn’s disease and ulcerative colitis patients (Federici et al, 2022). A similar observation was seen in patients with primary sclerosing cholangitis (Ichikawa et al 2023). Gut colonization of K. pneumoniae can also lead to subsequent serious infections such as liver abcess and septicemia, particularly in immunocompromised individuals.

The IBD study identified a specific clade of K. pneumoniae associated with the condition: ST323

In both studies, phages were considered as a therapeutic option in rodent models, with promising results. Phage modulation of the gut microbiome was tolerated and successful, providing evidence that phages can be a therapeutic alternative beyond classical bacterial infections.

KlebPhaCol contains two ST323 strains targeted by 5 of the phages in the collection (RothC, RothD, RothG, RothI, RothJ).

This only showcases the potential of utilizing this collection outside of what is classically known as Phage Therapy.