FIGURE 3

Larval zebrafish facial lymphatic vessel network. (a) Schematic drawing of main lymphatic networks of facial, lateral intestinal and trunk regions of the zebrafish larvae in lateral view. Lymphatic vessels in each network are classified and color-coded as indicated. (b) Schematic depicting location of facial lymphatic vessel (red) and primary head sinus (blue) on transmitted light image of a zebrafish larval head. Box denotes region in (c), dotted line indicates plane of section shown in (f). (c) Confocal image of blood vessels (blood vascular endothelial cells, BECs, express green fluorescent protein) and facial lymphatic vessel endothelial cells (LECs, red). PHS, primary head sinus; LV, lymphatic valve; FLV, facial lymphatic vessel. (d) Confocal lymphangiography of FCLV and FLV in zebrafish larva at 7 dpf. LECs express green fluorescent protein. Regions with and without QDot perfusion (red) are indicated. Asterisk denotes location of QDot injection. (e) Confocal lymphangiography depicting facial lymphatic vessels and PHS. Ventral view, anterior to the left. Position of the lymphovenous valve (LVV) and LV are shown. Arrows indicate direction of flow from FLV to FCLV and back into the PHS. (f) Transverse section of trypan blue-stained zebrafish larva. Lumens of PHS and FCLV are blue and light green, respectively. Frontal view, dorsal is up. HS, hyosymplectic cartilage; IMB, inner muscle bundle; OMB, outer muscle bundle; Pch, parachordal cartilage. Image courtesy of Sumio Isogai. Schematic illustration (a) is modified from Okuda et al. (2012), with permission. Schematic and images (b–d) are re-used from Shin et al. (2019), while (e) from Shin et al. (2016) with permissions