Figure 1

Sterile injury-induced neutrophilic inflammatory responses are exacerbated in the absence of CFTR. (A–C) Neutrophil chemotaxis to sterile tissue lesions in WT, cftr –/– mutant (cftr –/–) and cftr morphant (cftr MO) TgBAC(mpx:EGFP)i114 zebrafish larvae. (A) Larvae were tail amputated then the number of neutrophils mobilized to the site of injury (dotted lines) has been observed and counted by fluorescent microscopy throughout inflammation. The wound area is defined as the region between the amputation edge and caudal hematopoietic tissue end (CHT). (B) Dynamics of neutrophil recruitment towards the wound over 24 h (n = 30; two-way ANOVA with Tukey post-test). (C) Representative confocal images of injured tails at 4 hpi (scale bars, 200 μm). (D,E) Total number of neutrophils (D) in whole TgBAC(mpx:EGFP)i114 larvae (n = 18; one-way ANOVA with Dunnett's post-test). (E) Microscopy revealed a disorganized neutrophilic distribution in CFTR-depleted animal compared to control counterpart (scale bars, 200 μm). (F) Neutrophil mobilization into the otic cavity (oc, dotted lines) in response to DMSO or fMLP injection in TgBAC(mpx:EGFP)i114 larvae monitored at 2 h-post injection. Representative photomicrographs of fMLP-injected animal compared to DMSO-injected control (top panel; scale bars, 50 μm). Neutrophil counts (n = 18; one-way ANOVA with Dunnett's post-test) (bottom panel). See also Supplementary Figure 1.