FIG 3 .

PPMOs rescue colistin activity in a mouse model of acute septicemia. Female BALB/c mice (7 to 8 weeks old) were infected via intraperitoneal injection with 8e4 CFU of MRSN 388634. At 2 and 6 h postinfection, 0.25 mg/kg colistin sulfate, 100 μg PPMO (~5 mg/kg), or the combination was administered via the i.p. route. Mice were euthanized at 24 h, and organ burden was determined. Numbers of CFU per gram of tissue of the liver (A) and spleen (B) are shown. (C) Morbidity was assessed immediately prior to euthanasia and scored as a maxima of 6 (moribund) and a nadir of 0. Mice that succumbed prior to euthanasia are depicted with the maxima score of 6. The data represent the means and standard errors of the means (SEM) of results from two replicate experiments (n = 4) (n = 8 per group total). n.s., not significant; *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001 by Student’s t test, with the Mann-Whitney test used for morbidity.