ABSTRACT
Objective To evaluate the BALB/c murine infective effects in different concentrations and different aerosol challenge times by Bordetella pertussis.Methods Four experiment groups according to different concentrations and different aerosol challenge times were designed.BALB/c murines were challenged by aerosol way.Group 1: 1010cfu/mL Bordetella pertussis challenge 15 min, group 2: 1010cfu/mL challenge 30 min, group 3: 109cfu/mL challenge 30 min, group 4: 1011cfu/mL challenge 30 min, using the normal saline challenge 30 min as control.At 0d,3d,7d,14d and 21d after challenge, the WBCs of all groups were measured and lung tissues were homogenized to calculate the bordetella pertussis clone in lung.Results After 3 days of challenge, WBCs in all groups were slightly increased.The WBCs of group 1, group 2, group 3 and group 4 were significantly increased after 7 days, with the average numbers of 8.52×109 per/L, 1.74×1010per/L, 1.15×1010per/L and 5×1010per/L, respectively.After 14 days, they were 1.77×1010per/L, 1.67×1010per/L, 1.27×1010per/L and 3.84×1010per/L respectively.WBCs in all groups were dramatically declined after 21 days.The WBC of negative control group had no obvious change during the whole process with the stable number of 3.4~7.0×109per/L.Bordetella pertussis were detected in lung of all experimental groups in each sampling point.The CFU in lung wase at peak at 7d or 14d after challenge, which was obviously decreased at 21d.Conclusion This aerosol challenge method can establish a bordetella pertussis infection mouse model successfully.