FIG. 4.
Lung colonization by B. pertussis mutants. OF1 mice were infected i.n. with B. pertussis BPGR4 (open squares), BPDR (black circles), or BPDR-RE (black triangles), and colonization was monitored as described for Fig. 1. The stippled line represents the limit of detection of the number of CFU present in the lungs.