Fig. 4.

Lung cellular infiltrates post-challenge. Mice were immunized 3x, 3 wks apart with saline, 20 μg GLA-SE, 8 μg ID93/GLA-SE, or once with 5×10⁴ live BCG. Four weeks after the last boost, mice were challenged with an aerosol dose of 50 – 100 H37Rv bacilli. Lung cell phenotype and in vitro cytokine recall responses to ID93 were measured by intracellular cytokine staining and flow cytometry 4 wks after challenge. (A) Number of Gr-1⁺ cells in the lungs. (B) Number of T cells (x 10³), identified based on CD3 expression, and further gated as CD4^-CD44^lo, CD4^-CD44^hi, CD4⁺CD44^lo or CD4⁺CD44^hi. (C) Number of CD44^hiCD4⁺ and CD44^hiCD8⁺ T cells expressing TNF and/or IFN-γ in response to media (“-Ag”), ID93 (10 μg/ml) or PPD (10 μg/ml) stimulation. Mean + SD (n = 2 pools of 3 mice each) are shown for a representative experiment. (D) Proportion of cells expressing IFN-γ, TNF, or TNF/IFN-γ effector cytokines in response to ID93 in vitro stimulation.