Bacteriophage-Loaded Nanostructured Lipid Carrier: Improved Pharmacokinetics Mediates Effective Resolution ofKlebsiella pneumoniae–Induced Lobar Pneumonia

This study examined the therapeutic and prophylactic potential of bacteriophages in a mouse model of Klebsiella pneumoniae lobar pneumonia. Phages were administered intraperitoneally. Liposome-entrapped phages (LP) were effective in treating infection, even when therapy was delayed by 3 days after the induction of pneumonia. In contrast, nonliposomal phages provided protection when administered 24 hours after infection. Administration of nonliposomal phages 6 hours prior to intranasal bacterial challenge resulted in complete protection, compared with LP, which was effective even when administered 48 hours prior to infection. Increased reduction and a greater increment in the levels of proinflammatory and antiinflammatory cytokines, respectively, in homogenates of lung from LP-treated mice were suggestive of increased efficacy of LP in the treatment of pneumonia. This is the first study to assess liposomes as a delivery vehicle for phage, and the results confirm the superiority of LP for both therapeutic and prophylactic applications.