Fig. 7.

Class III β-tubulin expression by lymphatic blind ends during peak lymphatic sprouting. Immunolabeling of PECAM (red) and class III β-tubulin (green) identified distal ends of lymphatic capillaries, resembling lymphatic sprouts. (A) A representative microvascular network 30 days post-stimulation labeled for PECAM (red) and class III β-tubulin (green). Class III β-tubulin identified distal lymphatic segments (white arrows). Blood vessels and proximal lymphatic vessels (open arrows) did not label positively for class III β-tubulin. (B–D) Confocal projection from the outlined box in (A) confirming the co-localization of PECAM and class III β-tubulin labeling on endothelial cells of lymphatic vessels (L), but not blood capillaries (BC). Lymphatic capillaries expressing class III β-tubulin commonly contained filopodia extensions (arrowheads). Scale bars=(A) 200 μm; (B–D) 20 μm.