Lymphatic vasculature in human dural superior sagittal sinus: Implications for neurodegenerative proteinopathies

Recent reports have characterized functional lymphatic vessels, which drain both fluid and immune cells from the CSF to the deep cervical lymph nodes, lining the dural sinuses in mice. If conserved in the human brain these vessels could have profound implications for neuroinflammatory and neurodegenerative diseases. We provide evidence of the presence of lymphatic vessels in human dura obtained at autopsy, at the level of the superior sagittal sinus, in 4 individuals. Immunohistochemistry for the lymphatic vessel endothelial cell marker podoplanin revealed the widespread presence of multiple structures with a distinct lumen distributed throughout the superior sagittal sinus. These vessels provide a putative infrastructure for drainage of macromolecules from the brain parenchyma and represent an exciting avenue of exploration for involvement in the pathogenesis of neurodegenerative proteinopathies including Parkinson's disease.