FIG. 3.

TTSS-mediated effect on cytotoxicity and virulence of B. bronchiseptica strains RB50 and 1289. (A) Cytotoxicity in J774 macrophages treated with medium or infected with RB50, RB50ΔbscN, 1289, or 1289ΔbscN for 1, 2, 3, and 4 h at an MOI of 10. The error bars represent the plus-or-minus standard deviations. (B) Groups of three or four C57BL/6 mice were inoculated intranasally with the indicated doses of strains RB50ΔbscN or 1289ΔbscN. Survival curves were generated by inoculating mice with the indicated dose and determining the percent survival over a 28-day period.