Establishment of murine TB infection model.

Female BALB/c mice, weighing 18 to 20 g (in-house breeding), were obtained from Beijing Vital River Laboratory Animal Technology Co., Ltd. Five mice were housed in each cage with sterile shaving for bedding. The temperature was maintained at 21 ± 2°C, and the relative humidity level was 55% ± 15% with a 12:12 h dark-light cycle. The mice were allowed free access to water and food. Log-phase M. tuberculosis H37Rv strains were suspended evenly with 5 × 10⁶ CFU/ml for aerosol infection (099C A4224 inhalation exposure system; Glas-Col). For acute and chronic models, the baseline bacterial load could be determined after 10 days and 6 weeks of aerosol infection, respectively. The mice were randomly assigned to treatment groups.