FIG. 5.
CI for the plcBΔpro mutant relative to the Emr wild type after oral or intravenous infection of BALB/c mice. Six- to 8-week-old female BALB/c mice were initially infected with equal concentrations of the Emr wild type and the plcBΔpro mutant. At defined time points (2 to 4 days for oral infection; 7 h and 1 to 3 days for i.v. infection), mice were sacrificed, and bacteria residing in various organs were enumerated. Livers and spleens were harvested from mice infected intravenously. In addition to these two organs, whole intestines and MLN were harvested from mice infected orally. Each dot represents the CI for an individual mouse. Crossed dots represent estimated CI when the mutant was not recovered from the corresponding mice. The horizontal lines represent the median CI for each treatment group. A CI of <1 indicates that the plcBΔpro mutant's virulence was attenuated. Data were analyzed with a one-sample t test. *, P < 0.05; **, P < 0.001; ***, P < 0.0001.