Figure 5.

Killing of A. fumigatus hyphae exposed to human granulocytes for two h. A. fumigatus conidia expressing mitochondria-targeted GFP were inoculated in RPMI-1640 and incubated at 37°C. After 10 h, granulocytes were added. After 2 h incubation, samples were fixed and stained with calcofluor white to visualize hyphae. GFP and calcofluor white fluorescence images of optical stacks covering the entire hyphae in focus and bright field images were taken with a confocal laser scanning microscope. Upper panels show the mitochondrial morphology (green) with magnifications of the framed sections. Lower panels show overlays of bright field, GFP fluorescence and calcofluor white fluorescence. Exemplary images of hyphae or hyphal compartments with tubular (A), partially tubular (B) or completely fragmented and clustered mitochondrial morphologies (C), and of a hypha with fading GFP fluorescence (D). An asterisk marks a viable compartment (C), directly adjacent to a compartment with fragmented and clustered mitochondrial morphology. Bars represent 4 μm.