Fig. 4

Variations of vLV pattern along the vertebral column. a–f Pattern of PROX1⁺ LVs in the cervical (a, b), thoracic (c, d), and lumbar (e, f) vertebral column, spatial orientation (D: dorsal, L: lateral, V: ventral). Left panels show frontal views, right panels show connection to peripheral lymph nodes (LN) and thoracic duct (TD). a, c, e Note fewer LVs in the dorsal plexus between intervertebral spinous processes of cervical and lumbar vertebrae compared to thoracic ones (blue arrows). a LVs exit bilaterally (red arrows) through the intervertebral foramen. a, c, e Also note differences in ventral root exit circuits between regions (salmon arrows). b, d, f LV ventral exit circuits (green) to b deep cervical LNs, d thoracic duct, or f to renal LNs. Red asterisk: vertebral ventral body; SC: spinal cord; Ao: Aorta. Scale bars: 300 µm (a–f)