Fig. 5

INH/PYZ treatment compromises the ability of alveolar macrophages to control Mycobacterium tuberculosis growth. Mice were treated with INH/PYZ or RIF for 8 wks. Following treatment, alveolar macrophages were harvested from the BAL and bone marrow cells were differentiated into BMDM using L929-conditioned media. a, b Alveolar macrophages and c, BMDM were infected with Mtb (MOI 1) for 4 h. Intracellular bacterial burden was assessed by plating serially diluted cell homogenates on day 3. d Bacterial load in alveolar macrophages pretreated with RIF or INH + PYZ in vitro. e Schematic representation of the alveolar macrophage transfer strategy. Alveolar macrophages were harvested from INH/PYZ-treated or control mice, infected with H37Rv (MOI 0.5) and adoptively transferred (intratracheally) into Rag1−/− mice (3 × 10⁵ cells/mouse) and lung Mtb burden was quantified 3 weeks later. f Bacterial burden in the lungs (n = 5 per group) of Rag1−/− mice 3 weeks after adoptive transfer of Mtb-infected alveolar macrophages. g Mtb burden in alveolar macrophages harvested from INH/PYZ or control-treated mice 6 days after aerosol infection. Data shown are pooled from two independent experiments a–d, g or one experiment e, f. e Error bars represent mean ± SEM; *p < 0.05, **p < 0.01