FIG 4.

In vivo competition of hvKP1 (wt) and hvKP1Δpeg-344 in CD1 mice after subcutaneous or pulmonary challenge. Strains were grown overnight in LB medium and diluted in 1× PBS, and equal volumes of hvKP1 and hvKP1Δpeg-344 were mixed to enable codelivery via pulmonary or s.c. challenge. At 24 and 48 h, animals were euthanized, and bacterial titers of each strain in blood, lungs, kidney, and spleen were determined as described in Materials and Methods. (A) Mice underwent pulmonary challenge with 1.2 × 10⁴ CFU of hvKP1 and 1.7 × 10⁴ CFU of hvKP1Δpeg-344. The line indicates the median for each strain (P = 0.06, as determined by a Wilcoxon signed-rank test, for hvKP1 compared to hvKP1Δpeg-344 at 24 h for blood, lungs and spleen). (B) Mice underwent s.c. challenge with 1.2 × 10⁴ CFU of hvKP1 and 1.7 × 10⁴ CFU of hvKP1Δpeg-344. The line indicates the median for each strain.