Figure 3. BL/6 Stat4-/- mice demonstrate enhanced lung M2 macrophage polarization.
C57BL/6 WT and Stat4-/- mice and Balb/c WT and Stat4-/- mice were administered 2 × 105 Pneumocystis cysts via intratracheal inoculation. (A/B/C/D) Fourteen and (E/F/G/H) twenty-eight days post-inoculation, the right lung was collected and total RNA isolated, transcribed to cDNA and quantitative real-time PCR was performed for Retnla (A/B/E/F). Gene expression was normalized to Gapdh and fold changes between WT (set at 1) and Stat4-/- mice were determined using the 2-ΔΔCt method. Of note, there were no differences in the delta Ct values (Ct value of Retnla minus Ct value of Gapdh) when comparing C57BL/6 WT mice and Balb/c WT mice at 14 and 28 days post-challenge. For CCL17 analysis (C/D/G/H), mice were infected as described and twenty-eight days post-inoculation, the left lung was collected and homogenized in PBS supplemented with Complete Mini protease inhibitor tablets and supernatants clarified by centrifugation. CCL17 levels were determined in lung homogenate supernatants by ELISA. Cumulative data are shown from three independent studies with n = 4-6 mice/group per study. (A/B/E/F) Data is expressed as mean fold-change. ** represents a P value of < 0.01 (Paired two-tailed Student's t test). (C/D/G/H) Data is expressed as mean pg/ml + SEM. * represents a P value of < 0.05 (Unpaired two-tailed Student's t test).