Fig 4.

Protective effect of D3112 in mice and flies. (A) Mortality of PA14 (2 × 10⁵ CFU)-infected mice (n = 20) with either MP22 (□ and ■) or D3112 (○ and ●) at 2 × 10⁸ PFU per 100 μl, which was administered by the i.m. route (open symbols) or by the i.p. route (solid symbols) at 6 h postinfection. One hundred percent of PA14-infected mice with MP22 treatment or without phage treatment (♢) died within 84 h. Statistical significance, based on the log rank test, was set at P values of <0.001 (***). (B) Bacterial burdens in lung, spleen, and liver of mice treated with or without i.p. administration of either MP22 or D3112 (2 × 10⁸ PFU in 100 μl). The numbers of viable bacteria (CFU) were determined from the organs of live mice at 24 h postinfection. The CFU per unit volume (ml) were determined as described in Materials and Methods and are shown on a log scale. Symbols: ♢, no phage treatment; □, MP22; ○, D3112. (C) Mortality of PA14 (either wild type [WT] or its isogenic pilA mutant)-infected flies (n = 33) fed with phages. Infected flies were transferred to a new medium overlaid with nothing (♢ and □) or phage samples (5 × 10⁹ PFU) of either MP22 (■) or D3112 (●). The dotted line represents the time required to reach 50% mortality. Statistical significance, based on the log rank test, was set at P values of <0.001 (***). (D) Bacterial burdens in fly homogenates fed with phages were measured as the number of bacteria (CFU) from the homogenates of an individual live (open symbols) or dead (solid symbols) fly at 0.5 h, 12 h, 24 h, or 48 h postinfection. The CFU per fly are shown on a log scale. Symbols: □ and ■, MP22 feeding; ○ and ●, D3112 feeding.