Jax balb cbyj mice

The bacteria were grown on BGA for 48 h and resuspended in sterile PBS to 10⁶ bacteria per 20 µL. Female, 6-weeks-old JAX ™ BALB/ cByJ mice (Charles River) were anesthetized intraperitoneally with a mixture of ketamine, atropine, and valium and infected by intranasal inoculation with 10⁶ bacteria. Groups of 3-5 animals per bacterial strain were sacrificed 3 h, and 4, 7, 14, or 21 days post-inoculation. Their lungs and naso-pharynxes were removed in a sterile manner and homogenized using an Ultra Thurax apparatus^{59 (link)}. The suspensions were serially diluted in PBS and plated onto BGA for CFU counting. All the experiments were carried out in accordance with the guidelines of the French Ministry of Research regarding animal experiments, and the protocols were approved by the Ethical Committees of the Region Nord Pas de Calais and the Ministry of Research (agreement number APAFIS#9107 ± 201603311654342 V3).

After 36 h of growth on standard Bordet-Gengou (BG)-blood plates or plates containing 50 mM MgSO₄ to modulate the various strains, bacteria were resuspended in sterile PBS to 10⁶ bacteria per 20 μL. After intraperitoneal anesthesia with a mixture of ketamine, atropine and valium, female 6-weeks-old JAX BALB/cByJ mice from Charles River were infected by intranasal inoculation with 10⁶ bacteria. Groups of 5 animals per bacterial strain were sacrificed by cervical dislocation after 3 h and 3, 7, 14 or 28 days post-inoculation in the first experiment, and groups of 3 animals after 3 h and 7, 14 or 21 days in the second. Noses and lungs were collected and homogenized using an Ultra Turrax apparatus. Serial dilutions were performed in PBS and plated on BG agar plates to count the bacteria. All the experiments were carried out in accordance with the guidelines of the French Ministry of Research regarding animal experiments, and the protocols were approved by the Ethical Committees of the Region Nord Pas de Calais and the Ministry of Research (agreement number APAFIS#9107–201603311654342 V3).

The bacterial strains used for the animal experiments were grown on plates for 48 h, scraped and resuspended in sterile PBS to 10⁶ bacteria per 20 mL. Female, 6-weeks-old JAX ™ BALB/cByJ mice from Charles River were anesthetized intraperitoneally with a mixture of ketamine, atropine and valium and infected by intranasal inoculation with 10⁶ viable bacteria (S1 Fig). Groups of 3 or 4 animals per bacterial strain were sacrificed after 3 h, and 4, 7, 14 or 21 days post-inoculation in the first experiment, and after 3 h and 5 days post-inoculation in the second. Their lungs were removed in a sterile manner and homogenized using an Ultra Thurax apparatus. Serial dilutions were performed in PBS and plated to count the bacteria. All the experiments were carried out in accordance with the guidelines of the French Ministry of Research regarding animal experiments, and the protocols were approved by the Ethical Committees of the Region Nord Pas de Calais and the Ministry of Research (agreement number APAFIS#9107–201603311654342 V3).