Postnatal development of lymphatoc vessels in the brain meninges
Thursday, September 14, 2017 — Poster Session III
- RM Izen
- Y Mukouyama
Traditionally, the central nervous system (CNS) has been viewed as an immune-privileged environment with no lymphatic vessels. This view was partially overturned by the discovery of lymphatic vessels in the dural membrane that surrounds the brain, in contact with the interior surface of the skull. The unique distribution of these lymphatic vessels poses fundamental questions: How does the CNS lymphatic vasculature develop on the surface of, but not within, the brain? What is the developmental origin of these lymphatic vessels? Using the Prox1-GFP BAC transgenic reporter and immunostaining with antibodies to lymphatic markers LYVE-1, Podoplanin, PECAM-1, and Prox-1, we have carried out whole-mount imaging of dural lymphatic vasculature at postnatal stages. We have found that between postnatal day 6 (P6) – P13, lymphatic vessels extend alongside dural blood vessels from the side of the skull towards the midline. Between P13 - P20, lymphatic vessels along the Transverse Sinuses reach the Superior Saggital Sinus (SSS) and extend along the SSS to the olfactory bulb. Compared with the embryonic developmental timing of lymphatic vessels in other tissues, e.g. skin and mesentery, dural lymphatic vessel development is dramatically delayed. The delay suggests that a unique mechanism controls dural lymphatic vessel development.