Brain drain, meningeal lymphatics and neurlogical disorders

The central nervous system (CNS) was considered to be devoid of classical lymphatic drainage. We recently challenged that paradigm by demonstrating the presence of a lymphatic vasculature in the surrounding of the brain called the meninges. We demonstrated that lymphatic vessels, expressing hall the markers for lymphatic endothelial cells (LEC; i.e Lyve-1, Prox1, podoplanin, VEGFR3 and CCL21) are located along the dural sinuses. They present features of initial lymphatic through the absence of surrounding smooth muscle cells and lymphatic valves, along with presenting a punctate expression pattern for adhesion molecules (Claudin-5 and VE-Cadherin). Finally, we demonstrated that these vessels drain fluids, macromolecules and immune cells from the cerebrospinal fluid into the deep cervical lymph nodes. Our recent efforts are concentrated on understanding the role of meningeal lymphatic vessels in CNS function in health and disease. Our results suggest that the drainage into the deep cervical lymph nodes might play different roles at different stages of several neurological diseases. Understanding the function of the lymphatic drainage in CNS might shed a new light on neurological disorders and offer new therapeutic targets. Dr. Kipnis has nothing to disclose nor any conflicts of interests to declare.