Campylobacter jejuni mouse infection

Prior to the infection C. jejuni strain 81-176 was derived from frozen stocks, inoculated on karmali agar plates (Oxoid, Wesel, Germany) and grown at 37°C under microaerophilic conditions (CampyGen gas packs, Oxoid, Wesel, Germany). After 2 days of incubation one fluently grown karmali plate was chosen for harvest and incorporated in 5 mL sterile phosphate-buffered saline (PBS; Thermo Fisher Scientific, Waltham, MA, USA). This resulted in an optical density of 0.6 at 600 nm wavelength with a yield of 10⁹ viable bacterial cells. On days 0 and 1, a volume of 0.3 mL of the C. jejuni suspension was used to gavage each SAB IL-10^–/– mouse. The yield of 10⁹ colony-forming units (CFU) was respectively confirmed by serial dilutions and culture of the bacterial suspensions on solid culture media as described recently (Du et al., 2022 (link)).