Figure 2: Confocal laser scanning microscopic images of a novel threadlike structure (NTS). Images show serial optical sections (panels (a–d); 1 μm thick) of an NTS-containing lymphatic vessel stained with acridine orange. The arrows indicate the NTS within the lymphatic vessel. Panel (b) shows the distinct protrusion of the NTS from the lymphatic vessel (dotted oval). Scale bar in all panels is 100 μm.