Total # of IFN-γ⁺ T cells in BAL in mice boosted at 16 weeks post-BCG (x 10³).

Infant and adult mice were immunized s.c. with BCG, and the AdHu5Ag85A booster vaccine was administered intranasally (i.n.) at 16 weeks post-BCG. The mice were sacrificed 4 or 8 weeks after boosting. Cells isolated from the BAL were stimulated with M.tb CF + crude BCG, or unstimulated as a control. Cells were stained with extracellular antibodies for T cell markers, followed by intracellular staining for IFN-γ, and analyzed by flow cytometry. Absolute numbers of IFN-γ+CD4+ and IFN-γ+CD8+ T cells were calculated (unstimulated subtracted from stimulated). Results are from one experiment per timepoint, n = 4-5/group/timepoint. Data are expressed as Mean ± SEM. *, p < 0.05. Total # of IFN-γ+ T cells in BAL in mice boosted at 16 weeks post-BCG (x 103).