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DVDY_22306_sm_suppFig-S1.tif7319KSupp. Fig. S1. Expression of α-SMA in room air control retinas. α-SMA expression was restricted to arteries (a), and not appreciated on veins (v), similar to that of ephrinB2 at P8 (A) and P12 (B). However, one noted difference was the extensive branching of ephrinB2 expression along arterioles as compared to α-SMA, which was restricted to the arterial trunk and primary branch points only. Retinal whole mounts from P17 room air B6WT mice (C) begin to show more α-SMA expression branching off the arterial trunk, in addition to some faint expression along the vein.
DVDY_22306_sm_suppFig-S2.tif7429KSupp. Fig. 2. Expression of α-SMA following hyperoxia exposure. Similar to ephrinB2, α-SMA expression was not drastically altered following hyperoxia exposure on P8 (A) and P12 (B), with expression observed on arteries (a) and not veins (v). In addition, intense α-SMA expression was observed on P17 (C), the peak of retinal neovascularization, along arteries (a), veins (v), and capillaries (*), as well as on neovascular tufts (C, arrow). Furthermore, the presence of arteriovenous malformations (AVM) was confirmed at P17 following hyperoxia exposure (C).
DVDY_22306_sm_suppFig-S3.tif6624KSupp. Fig. 3. High-magnification confocal microscopy of regressing veins. Normal morphological analysis of a vein from a room air–reared mouse (A) at P8, compared to that of a mouse exposed to 24 hr of 75% oxygen (B). Representative images of isolectin (red) labeled veins depict a single Z-section through the middle of the vein; note the typically large lumen (asterisk) in the room-air control vein (A), compared to that nearly absent lumen in the regressing vein of the hyperoxia-exposed mouse (B). C,D: Additional representative single Z-stacks of image B, taken through the edge of the vessel, which demonstrate caspase-3-positive cells within the vessel wall are shown. Retinas were immunostained for lectin (red), activated caspase-3 (green), and DAPI (blue). Scale markers = 15 μm. Green lines in the cross-sectional views show the level of the single Z-stack seen enface, while yellow lines in the enface view show the region viewed in the cross-sectional panels.
DVDY_22306_sm_suppFig-S4.tif5635KSupp. Fig. S4. Arteriovenous Malformations (AVM). Representative images of isolectin (red) and β-galactosidase (green; ephrinB2) -labeled retinas at P15 following hyperoxia-exposure. Intense ephrinB2 expression is observed along major arteries (a) and weakly present on veins (v). Arteries on both sides of a vein directly anastomose to this vessel creating a double AVM (arrow). The proximal vein that is located in the retinal periphery (arrowhead) exhibits minimal ephrinB2 expression.

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