Decolonization of carbapenem-resistant Klebsiella pneumoniae from the intestinal microbiota of model mice by phages targeting surface structures

Background: Klebsiella pneumoniae is a normal component of the human gastrointestinal tract microbiota. However, in some cases, it can cause disease. Over the past 20 years, the prevalence of antibiotic-resistant bacteria, such as carbapenem-resistant K. pneumoniae (CRKP), has been increasing.Methods: We attempted to specifically eliminate CRKP from a mouse model with human intestinal microbiota. To establish humanized microbiota-colonized mice, we administered K64 CRKP-containing human microbiota to germfree mice by faecal microbiota transplantation. Then, we used two phages, one targeting the capsule (phage K64-1) and one targeting O1 lipopolysaccharide (phage KO1-1) of K64 K. pneumoniae, to eliminate CRKP.