Figure 8.

Figure 8.

Tg(tnfa:eGFP-F;mpeg1:mCherry-F) (A-B) or Tg(il1b:eGFP-F x mpeg1:mcherry-F) (C) zebrafish larvae (5dpf), were injected with n = 200 T. carassii or with PVP. At 4 dpi, high-infected individuals were imaged with an Andor (A-B) or Roper (C) Spinning Disk Confocal Microscope using ×40 magnification. Scale bar indicates 25 μm. Foamy macrophages (asterisks) were easily identified within the caudal vein (dashed lines) and were strongly positive for tnfa (A) and il1b (C) expression (GFP signal). (B) Same as A, but a few stacks up, focusing on the cells lining the endothelium. Macrophages that were partly inside and partly outside the vessel (yellow arrowhead) were also strongly positive for tnfa, whereas macrophages lining the outer endothelium had a lower tnfa expression (white arrowheads). (C) A foamy macrophage (asterisk) within the caudal vein (dashed lines) positive for il1b. Endothelial cells were also strongly positive for il1b, a selection of which is indicated by white arrows. A mCherry-negative-il1b positive cell is present outside the vessel (blue arrow). Given its position, it is likely a neutrophil.