Human Dermal Lymphatic Endothelial Cells

Human dermal lymphatic endothelial cells (HDLECs) are a type of monolayer flat epithelium that are tightly arranged on the inner surface of lymphatic vessels, forming the primary structure of the lymphatic vessel wall. Through their precise arrangement and structure, they ensure effective lymph transportation and the normal functioning of the lymphatic system. HDLECs typically lack a complete basement membrane, which endows them with high permeability, favoring the exchange of substances between lymphatic fluid and tissue fluid. Moreover, HDLECs possess numerous invaginations and cytoplasmic vesicles, along with characteristic overlapping intercellular junctions. These structural features enhance the strength of intercellular connections and help maintain the integrity and stability of lymphatic vessels. Additionally, HDLECs exhibit positive reactions to specific immunofluorescence markers such as CD31, Podoplanin, and Lyve1, which are commonly used for the identification and isolation of these cells.

HDLECs play a vital role in maintaining physiological balance and immune functionality within the human body. They not only manage fluid, protein and tissue pressure but also serve as sites for lymphocyte recirculation and immune activity. Lymphocytes travel efficiently throughout the body, performing immune functions such as infection prevention and tumour surveillance via lymphatic vessels. Moreover, HDLECs are involved in various pathologic processes including wound healing, lymphoedema, and spreading of inflammation. Several new studies have shown that HDLECs play a pivotal role in tumor metastasis, modulating the spread routes of cancer cells through control of the creation and function of lymphatic vessels In research, HDLECs are often used in making models of lymphatic diseases, including lymphangioma, lymphangitis and lymphatic tuberculosis, in order to understand how these conditions can be treated. Besides these, HDLECs are widely applied to determine how lymphatic endothelial cells multiply, migrate and differentiate, and the molecular signalling networks controlling those functions.

Fig. 1. Human dermal lymphatic endothelial cells. DAPI: blue nuclei. Corresponding bright field images of CD31 and podoplanin immuno-stained cells appear to the right of each immuno-stained image. (Kong AM, Lim SY, et al., 2022).