Tail transection in zebrafish larvae as a model for inflammation. (A) Schematic drawing of a zebrafish larva at 3 dpf. The dashed red line shows a site of transection (in some studies, the transection site may not include the a part of notochord). (B–E) Confocal microscopy images of tail from amputated larvae of the following transgenic lines: Tg(mpeg1:mcherry-F)(B), Tg(mpx:GFP)(C), Tg(il1b:GFP)(D), Tg(mpeg1:mCherry-F/tnfa:eGFP-F)(E). Images were taken at 4 h post-amputation using a Nikon Eclipse Ti-E microscope with a Plan Apo 20X/0.75 NA objective. Images show accumulation of macrophage (B) and neutrophils (C), activation of the il1b gene (D), and tnfa expression in macrophage (E) near the wound. In (E), arrow heads indicate macrophages in which tnfa was activated.

Schematic overview of commonly used zebrafish larval inflammation models. (A) Transection of the tail fin. (B) LPS injection in the yolk sac. (C) CuSO4 immersion causing damage to the neuromasts. (D) LTB4 injection in the otic vesicle. (D′) LTB4 immersion. (E) Chemical-induced intestinal inflammation. All presented models induce leukocyte recruitment. Red cells represent macrophages and purple cells represent neutrophils (in some models, the macrophage infiltration is not shown because it has not been investigated in the studies cited in this review). Alternative zebrafish larval inflammation models, discussed in the text but not presented in this figure, include laser wounding-, tail fin incision-, LPS immersion-, and mutation-induced inflammation. For the tail fin transection/incision, CuSO4 immersion and intestinal inflammation models, adult zebrafish have been used as well.