Figure 7. GM-CSF application i.t. increases CD103⁺ DC migration, alveolar T lymphocyte recruitment, and viral clearance, which is associated with attenuated lung injury after PR8 infection.

WT mice were PR8 infected (or mock infected in selected experiments), followed by i.t. application of 5 μg GM-CSF or PBS plus 0.1% BSA. (A) At 7 dpi, the fraction of CD103⁺ DCs in MLNs was quantified by flow cytometry. (B) Absolute numbers of CD4⁺ and CD8⁺ T lymphocytes in BALF were determined by counting BALF cells and flow cytometric quantification of the CD45⁺SSC^loCD3⁺CD4⁺ and CD45⁺SSC^loCD3⁺CD8⁺ fractions, respectively, and (C) PR8 titers were determined from BALF by standard plaque assay. (D–F) At 7 dpi, AEC apoptosis (D), alveolar albumin leakage (given as ratio of BALF and serum FITC fluorescence in arbitrary units; E), and arterial oxygen saturation and partial CO₂ pressure (pCO₂; F) were determined. Data are mean ± SD. *P < 0.05, **P < 0.01, ***P < 0.005.