Figure 1.

Downregulation of mincle receptor in lungs of gut microbiota disrupted animals dampens anti-Mtb immunity. Mice were given ad libitum access to Abx supplemented drinking water for 4 wk, prior to aerosol challenge with Mtb (~100 CFU) and oral administration of TDB (50 μg). At 30 d post infection, lung cells were harvested and assessed for the (A) expression of mincle by qRT-PCR, depicted as fold change relative to control and normalized to β-actin and GAPDH reference gene; (B) Mtb burden by CFU assay. Further, (C–E) lung lymphocytes were stimulated with PPD (25 μg/ml) for 48 h. Thereafter, culture SNs was collected and quantified by ELISA for the secretion of (C) IFN-γ, (D) IL-17, and (E) IL-10. Data represented as mean ± SD are of three independent experiments (n = 5 mice/group). ^**p < 0.01, ^***p < 0.001. CT: control mice without Abx treatment; Abx: mice treated with Abx; Mtb: Mtb challenged mice; Mtb-TDB: mice with Mtb infection and TDB administration; Abx-Mtb: mice treated with Abx prior to Mtb infection; Abx-Mtb-TDB: mice with disrupted gut microbiota prior to Mtb infection and TDB administration.