Fig. 8: Spinal cord vascularization in day 12 WT larvae shows morphological similarities to tertiary sprouting. | Nature Communications

Fig. 8: Spinal cord vascularization in day 12 WT larvae shows morphological similarities to tertiary sprouting.

From: Parenchymal cues define Vegfa-driven venous angiogenesis by activating a sprouting competent venous endothelial subtype

Fig. 8

a Confocal images showing trunk vasculature at 10, 12 and 14 dpf in WT. Sprouts emanating from ISVs (blue arrowhead) and VTAs (yellow arrowhead). Representative images of 10 embryos per time point. b Confocal images of Tg(−0,8flt1:RFP; flt4:mCitrine) showing the arterial (flt1+, red)—venous (flt4+, green) identity of ISV and VTA derived sprouts at 14 dpf. c Confocal image showing a venous ISV expressing the venous marker CoupTFII in the ventral domain (yellow arrowhead), and two sprouts emanating from the dorsal aspect of this vISV (blue arrowheads) at 12 dpf. Blood flow indicated by dotted arrow. d Expression of arterial-venous identity markers flt1 and flt4 in ISV (left panel) and VTA (right panel) derived sprouts. Note: the majority of the ISV derived sprouts express the venous marker flt4, whereas all VTA derived sprouts express the artery marker flt1. Percentage; n = 50 sprouts for ISV derived and 39 sprouts for VTA derived from 19 animals. e Quantification of the percentage of ISV derived sprouts that emerged from a CoupTFII expressing vein. Percentage; n = 15 sprouts from 7 animals. f Confocal images of Tg(kdrl:TagBFP;fli1:nEGFP) showing EC nuclei in ISV (blue arrowhead) and VTA (yellow arrowhead) derived sprouts at 12 dpf. g Quantification of nuclei number in ISV and VTA derived sprouts. Mean±s.e.m.; n = 17 ISV derived sprouts and 12 VTA derived sprouts from 12 animals. h Injection of TexasRed-Dextran into Tg(kdrl:TagBFP) at 12 dpf to image blood plasma distribution, shows blood plasma in the ISV derived sprout consistent with the sprout being lumenized. In most VTA derived sprouts, no blood plasma was detected, consistent with absence of lumenization during the early stage of sprout remodeling. i Quantification of lumenization in ISV and VTA derived sprouts based on images in h. n = 15 ISV derived sprouts and 13 VTA derived sprouts from 11 animals. Scale bars indicate 50 µm in a; 20 µm in b, c, f and 10 µm in h. DA dorsal aorta, PCV posterior cardinal vein, ISV intersegmental vessel, VTA vertebral artery. Source data are provided as a Source Data file.

Back to article page