Internalization of A. fumigatus conidia by conducting airway wall neutrophils. (a) Frontal (x–y projection) and side (z–y projection) views of neutrophils (green) interaction with several (left panels) and single (right panel) conidia (magenta) in the conducting airway mucosa 6 h after the mice received A. fumigatus conidia; epithelium and smooth muscles are visualized by actin staining (SiRActin, light cyan) the nuclei (NucBlue, blue). Scale bar: 15 μm. (b) Three-dimensional surface-rendering images of the enlarged-indicated areas showing neutrophils (green, transparent) that uptake conidia (magenta) in close proximity to the apical side of airway epithelium (light cyan); smooth muscles are indicated in brown. Grid spacing: 5 μm.