LYVE1, also known as lymphatic vessel endothelial receptor 1 or lymphatic vessel endothelial hyaluronic acid receptor 1, is a member of the link protein family, which has the capability to bind with hyaluronic acid. A CD44 homolog, which is located primarily in lymphatic endothelial cells, LYVE 1 has a number of known functions, but research is ongoing and more could be established in the future. LYVE1 is encoded by the LYVE1 gene.
LYVE1 Mechanism and interactions
LYVE1 has similarities with CD44 in that it is a transmembrane receptor for extracellular matrix (ECM) glycosaminoglycan HA. HA is an abundant, naturally occurring component found in the skin and connective tissue cells. LYVE1 is mainly found in the endothelial cells that line lymphatic vessels. Studies suggest that HA turnover is considerably faster than other ECM components, with a half-life lasting around 24 hours.
LYVE1 is known as a homodimer. It interacts with PDGFB and IGFBP3. Classed as a type I integral membrane glycoprotein, in its capacity as a receptor, LYVE1 can bind to soluble and immobilised HA.
Research into the functions of LYVE1 is ongoing, but a number of potential purposes have already been defined. One primary function of LYVE1 is the transportation and turnover of hyaluronan, or HA. LYVE1 has also been found to play a role in HA localisation to the surface of the endothelial cells that line the lymphatic tissue. A number of studies have also flagged LYVE1 as a marker for lymphoid tissue and lymphangiogenesis. Hyaluronic acid has a diverse range of functions within the body, including: Cell migration, Morphogenesis of tissue, Inflammatory responses & Tumour metastases
When acting as a transporter for HA, LYVE1 can take on various roles, including moderating the uptake for catabolism within the lymphatic endothelial cells or delivering HA into the lumen of lymphatic vessels for reuptake in the lymph nodes. HA degradation tends to take place in the lymph nodes and it is also possible for fragments to migrate away from the lymph node and enter into the blood. In this case, the liver acts to break down the remaining HA.
As well as being involved in HA degradation and transportation, studies indicate that HA localisation towards lymphatic surfaces, which is linked to LYVE1, can affect the body’s immune responses and tumour metastases. HA can bind with CD44 in the presence of LYVE1, and therefore, LYVE1 could act as a substrate for tumour cells or migrating CD44+ leukocytes.