Figure 4.
Granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor β chain (GM-CSFRβ) signaling and neutrophil reactive oxygen species (ROS) production. Mixed bone marrow chimeric mice of wild-type (WT) and GM-CSFRβ−/− were infected with 3 × 107 AF293 fluorescent Aspergillus reporter (FLARE) and lungs and bronchoalveolar lavage (BAL) were harvested at 24 hours after infection. A, B, ROS production in neutrophils from lungs (A) and BAL fluid (B) were analyzed with flow cytometry. Median fluorescence intensity (MFI) for ROS levels was measured and normalized to the ROS levels in WT bystander neutrophils; data from 2 independent experiments were pooled and relative values are presented (n = 11). C, Neutrophils were enriched from the bone marrow of WT or p91phox−/− mice and cocultured with FLARE, with or without recombinant GM-CSF. Representative plots show fungal uptake and killing in neutrophils from WT and p91phox−/− mice, with live (R1) and dead (R2) conidia. D, Frequency of neutrophils (NPs) containing dead conidia (R2) was measured. C, D, Data from 1 experiment (n = 6). *P < .01; †P < .001; ‡P < .0001. Abbreviations: Byst, bystander neutrophils; Eng, fungus-engaged neutrophils; NS, not significant; PBS, phosphate-buffered saline.