Fig. 4

Fig. 4

NPC cells secrete FGF19 into HUVECs and promote angiogenesis. A: Tube formation assays (top) and Transwell migration assays (bottom) were performed to measure tube formation and migration of HUVECs treated with increasing doses of FGF19. B: The relative tube length and number of migrated HUVECs were quantified. C: Morphology of subintestinal vessels (SIVs) in Tg (fli1a: EGFP) transgenic zebrafish after the injection of FGF19 plasmid or negative control. Up: Morphology of subintestinal vessels (SIVs) was photographed by a fluorescence microscope. Bottom: Morphology of SIVs was photographed by a confocal microscope. Arrows: sprouts of SIVs. D: Relative FGF19 level in culture medium(CM) collected from CNE2 cells transfected with shFGF19 or oeFGF19 plasmids. E: Tube formation assays (top) and Transwell migration assays (bottom) were performed to measure tube formation and migration of HUVECs treated with different CMs. F, G: The relative tube length and number of migrated HUVECs were quantified. H: HUVECs pretreated with different CMs were mixed with Matrigel for subcutaneous injection. Top: Gross observation of angiogenesis in Matrigel plugs. Bottom: H&E staining was performed to observe blood vessel formation in different groups. Data represent the mean ± SD of three independent experiments. *P < 0.05, **P < 0.01, ***P < 0.001