The lymphatic system is an essential part of the immune system. It helps maintain tissue homeostasis, including interstitial protein transport, tissue fluid balance, and development of cellular immunity. Lymph nodes, which are located throughout the lymphatic system, contain large numbers of lymphocytes, macrophages and antigen presenting cells that together initiate primary immune response. Specialized lymphatic endothelial cells (LEC) in the cortex assist in the primary immune response by recruiting intravascular lymphocytes as they circulate past. In addition, LEC are responsible for facilitating the transmigration of intravascular lymphocytes into the reticular meshwork where the lymphocytes can interact with antigen presenting cells. LEC have been shown to be associated with chronic inflammation and cancers. HLEC from ScienCell Research Laboratories are isolated from human lymph node. HLEC are cryopreserved at passage one and delivered frozen. Each vial contains >5 x 105 cells in 1 ml volume. HLEC are characterized by immunofluorescence with antibodies specific to vWF/Factor VIII and/or CD31 (PECAM1). HLEC are negative for HIV-1, HBV, HCV, mycoplasma, bacteria, yeast, and fungi. HLEC are guaranteed to further expand for 10 population doublings under the conditions provided by ScienCell Research Laboratories. Recommended Medium It is recommended to use Endothelial Cell Medium (ECM, Cat. #1001) for culturing HLEC in vitro.