Fig. 6

Dexamethasone controls Mtb growth in human MDM. PBMC were isolated from buffy coats and MDM were adherence purified for 7 days in 10% human serum. MDM were treated with dexamethasone for 1 h prior to infection with Mtb (MOI 1–10). MDM were lysed and plated at 3, 48–120 h post infection on Middlebrook 7H10 agar supplemented with OADC (a-b). Alternatively, MDM were treated with bafilomycin A1 (50 nM) for 1 h (c) or rapamycin (250 ng/ml) for 24 h (d) prior to dexamethasone, infected with Mtb and lysed at 120 h. Data are represented as means ± standard deviation. Statistically significant differences were determined using a one-way ANOVA with Dunnett’s post-test (b, n = 8–17) or two-way ANOVA with a Holm-Sidak post-test (c-d, n = 8) (*p ≤ 0.05, ** p ≤ 0.01) or Student’s t-test (#p ≤ 0.05).