Fig. 7

The schematic of lymphatic vessels development in zebrafish. a Zebrafish possess an extensive lymphatic vessel network throughout the body. Specialized lymphatic vessels development in zebrafish includes facial lymphatic vessel development (b), intestinal lymphatic vessel development (c), and trunk lymphatic vessel development (d); b The facial lymphatic vessels of zebrafish undergo a step-wise assembly from 1.5 dpf to 4 dpf. The FLS are derived from the CCV beginning to form along the PHS. Subsequently, a group of ETV2-expressing cells, known as VAL, begin to fuse with the lymphatic sprouts to form the LFL along the PHS. The LFL then begins to bud out to form a complex facial lymphatic vessels including the OLV, LAA, and MFL; c The development of intestinal lymphatic vessels proceeds from 3 dpf–15 dpf. At 3 dpf-4 dpf, LECs sprout from the PCV to the ventral and bilateral sides, respectively to form segmental lymphatic vessels, which subsequently interconnect to form L-SIL, R-SIL. The SILs first bud toward the right side of the abdomen along the vascular network to form UR-IL and IR-IL. Finally, the lymphatic vessel network continues to expand follow the left vascular track to form UL-IL and LL-IL and take up intestinal lymph; d The formation of trunk lymphatic vessels is the earliest event of embryonic lymphatic vessel development in zebrafish, budding from the PCV to form the ISLV along the trajectory of the ISVs, and subsequently sprouting ventrally and dorsally to form the DLLV and TD, respectively. Dpf day postfertilization, CCV common cardinal vein, PHS primary head sinus, FLS facial lymphatic sprouting, VAL ventral aorta lymphangioblast, LFL lateral facial lymphatic vessel, OLV otolithic lymphatic vessel, ETV2 ETS variant transcription factor 2, LAA lymphatic branchial arches, MFL medial facial lymphatic vessels, PCV posterior cardinal vein, L-SIL the left supraintestinal vessel, R-SIL the right supraintestinal vessels, UR-IL upper-right intestinal lymphatics, LR-IL lower-right intestinal lymphatics, UL-IL upper-left intestinal lymphatics, LL-IL lower-left intestinal lymphatics, ISLV intersegmental lymphatic vessel, aISV arterial intersegmental vessels, vISV venous intersegmental vessel, PAC parachordal line, DA dorsal aorta, DLAV dorsal longitudinal anastomotic vessel, HM horizontal myoseptum, DLLV dorsal longitudinal lymphatic vessel, TD thoracic duct. Created with Adobe Illustrator