Figure 5

Extracellular ATP is not necessary for macrophage activation. (A) Schedule of the experiment. Fin folds from Tg(mpx:GFP) or Tg(mfap4:mCherry-F/tnfa:GFP-F) were injured at 3 dpf and larvae were immediately incubated in zebrafish water containing or not Apyrase and imaged at 6 hpA using epi-fluorescent or confocal microscopy. (B) Tail images are representative overlays of GFP fluorescence (neutrophils) and brightfield image. Images were acquired at 6 hpA by epi-fluorescent microscopy from Tg(mpx:GFP) larvae either untreated or treated with Apyrase. Scale bar: 100 μm. (C) Quantification of neutrophils recruited at the wound at 6hpA. Representative experiment of two independent experiments, mean ± SEM, n_larvae is indicated in brackets, one-tailed t-test with Welch’s correction, *p<0.05. (D) Tail images are representative maximum projections of the fluorescence of mCherry-F (macrophages), GFP-F (tnfa+ cells) and merged channel images with brightfield of Tg(mfap4:mCherry-F/tnfa:GFP-F) injured larvae after no treatment (control, up) or Apyrase treatment (down) at 6 hpA. Scale bars: 100 μm. (E) Quantification of recruited macrophages (up) and tnfa⁺ recruited macrophages (down) in controls and in Apyrase treated larvae at 6 hpA. Representative experiment of two independent experiments, mean ± SEM, n_larvae is indicated in brackets, upper graph: t-test, two-tailed, ns- not significant; bottom graph: Mann Whitney test, two-tailed, ns - not significant.