Lung colonization profile of <i>B. pertussis</i> KO<i>caps</i>:<i>kpsT</i> and KO<i>caps</i>:<i>kpsMT</i> strains.

<p>Balb/C mice were infected intranasally with 5×10⁵ CFU of <i>B. pertussis</i> BPSM (solid bars), KO<i>caps</i> (striped bars), KO<i>caps</i>:<i>kpsT</i> (dotted bars) and KO<i>caps</i>:<i>kpsMT</i> (open bars). At the indicated time points, four infected mice per group were euthanized and their lungs were harvested, homogenized and plated on blood agar to determine the total number of CFU per lung. The results are expressed as the mean ± SEM of four mice per group. ** <i>p</i> value<0.01 relative to KO<i>caps</i>. Results are representative of two independent experiments.