Figure 8

Figure 8

During copper exposure neutrophils migrate in association with blood vasculature to reach to the developing olfactory organ. (A) Frontal view of Tg(mpx:gfp);Tg(lyve1b:DsRed) 7 dpf larva. Boxed area (A′) with nasal LV (arrows, red) and neutrophils (green, asterisks). (B) Frontal view of Tg(mpx:GFP);Tg(lyve1b:DsRed) 7 dpf larva after 4 h of copper exposure, neutrophils (green, asterisks) associated with LV in ventral–lateral OO (arrowheads, red). Boxed area (B′) indicates cluster of neutrophils (asterisks, green). (C–D′) Images from Supplementary Video 4, Tg(fli1a:EGFP);Tg(gata1a:DeRed);Tg(mpx: GFP);Tg(OMP:RFP (quadruple transgenic larva of 5 dpf, showing OSN and erythrocytes in red, and neutrophils and endothelial vasculature in green. (C) Before copper exposure. Boxed area is magnified in (C′). Arrows indicate fli1a:EGFP+ branches that enclose the OO (Figure 2G′, NV, green). (D) After exposure to copper, more neutrophils are associated with the OO. (D′) Image from boxed area in (D). Asterisks indicate neutrophils that have migrated to the OO on the BV (NV) and clustered around the medial edge of the OO. (E–E″) A polarized neutrophil crawling (arrowhead) along the NV to finally enter the OO near the ventral basal ON (E″, see Supplementary Video 5). Minutes are posttreatment (pt). (F) Summary: Schematic of nasal blood and lymphatic vasculature at 5 dpf before and after exposure to copper. OO: olfactory organ, OB: olfactory bulb. fli1a:EGFP (green) and lyve1b:DsRed (red), neutrophils (blue) migrate in response to copper exposure using the NV (C′-D′), entering the OO near ventral ON exiting, and associating with ventral–lateral LV (A′-B′). Scale bars: (A–D) = 100 μm; (A′-D′,E–E″) = 50 μm.