FIG 4.

The growth of P. aeruginosa of a high inoculum in the HFIM is only controlled by the combination of phages with ciprofloxacin administered 4 h post phages. Population of bacteria (bacteria counts in log₁₀ CFU/mL) and of phage (phage counts in log₁₀ CFU/mL) in the HFIM over 72 h post exposure of a high inoculum of P. aeruginosa to the combination of ciprofloxacin and phages. (A and B) Combination of simultaneous administrations of ciprofloxacin with the two-phage cocktail (n = 2); (C and D) combination of the two-phage cocktail with ciprofloxacin administered 4 h post phages (n = 2). Solid lines represent total bacterial populations or total phage population, and dashed lines represent less-susceptible bacteria growing on agar containing 0.5 μg/mL of ciprofloxacin. Small graph is the magnification of the first 2 h of exposure. Square and circles represent independent experiments. The limit of detection (LOD) was 1.5 log₁₀ CFU/mL for bacteria and 1.5 log₁₀ PFU/mL for phages.