Lymphatic endothelium
The lymphatic endothelium is a specialised form of epithelium, distict from but similar to vascular endothelium. Although lymphatics were first described by Hippocrates in 400BC and rediscovered as "milky veins in the gut of a well fed dog" in the 1600s by Gasparo Aselli, they were ignored for centuries until in 1937 Howard Florey showed that lymphatics enlarge in inflamation. At this stage vascular and lymphatic endothelia were seen to be morphologically distinct and lymphatic vessels considered less important. Later it was discovered that VEGF-R3 and VEGF-C/VEGF-D were the key growth factors controlling lymphatic endothelial proliferation. Markers of lymphatic endolthelium were not discoovered until relatively recently. These being LYVE-1 (Jackson et al,1999)[1] and podoplanin [2]