Fig. 6

Neutrophils are required for VD₃-mediated control of bacterial growth in zebrafish. a Embryos microinjected with control buffer or sgRNAs targeting csf3r were collected at 6 dpf. Genotyping of csf3r amplicons was analyzed by qRT-PCR, and transcript levels of mpx were also tested. b Zebrafish larvae at 5 dpf were microinjected with E. tarda (approximately 200 bacteria/larva). The survival of the larvae in each group was recorded up to 25 hpi (n = 10 larvae/group/experiment, 2 independent experiments). Statistical analysis was conducted by Log-rank test. c–f Zebrafish larvae were immersed with 1 × 10⁸ CFU/mL E. tarda at 3 dpf. After 24, 48, and 72 h, the bacteria burden in the larvae was counted (n ≥ 14 larvae/group/experiment, 2 independent experiments). Data are represented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001. dpf, days post fertilization; VD₃, vitamin D₃; E. tarda, Edward-siella tarda; hpi, hours post infection; mpx, myeloperoxidase; WT, wild-type.