Lymphatic endothelial cells Last updated on Jul 14, 2021 Confocal micrograph of mouse heart stained for Lyve-1 positive cells (red), cell membrane (green) and nuclei (blue). Lymphatic endothelial cells are positively stained in red. The lymphatic system (arrows) is usually found accompanying vascular structures. Pinto Lab - Baker Heart and Diabetes Institute. Lymphatic endothelial cells (LECs) are specialised endothelial cells that form lymphatic vessels. Lymphatic vessels drain interstitial fluid from tissues. Marker genes: Lyve1, Prox1, Pdpn. Abbreviated cell population name(s): LEC.