Ectodomain Shedding of Lymphatic Vessel Endothelial Hyaluronan Receptor 1 (LYVE-1) Is Induced by Vascular Endothelial Growth Factor A (VEGF-A)

Abstract

Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), a type I transmembrane glycoprotein, is known as one of the most specific lymphatic vessel markers in the skin. In this study, we found that the ectodomain of LYVE-1 undergoes proteolytic cleavage, and this process produces soluble LYVE-1. We further identified the cleavage site for ectodomain shedding and generated an uncleavable mutant of LYVE-1. In lymphatic endothelial cells, ectodomain shedding of LYVE-1 was induced by vascular endothelial growth factor (VEGF)-A, an important factor for angiogenesis and lymphangiogenesis under pathological conditions. VEGF-A-induced LYVE-1 ectodomain shedding was mediated via the extracellular signal-regulated kinase (ERK) and a disintegrin and metalloproteinase (ADAM) 17. Wild-type LYVE-1, but not uncleavable LYVE-1, promoted migration of lymphatic endothelial cells in response to VEGF-A. Immunostaining analyses in human psoriasis skin lesions and VEGF-A transgenic mouse skin suggested that the ectodomain shedding of LYVE-1 occurred in lymphatic vessels undergoing chronic inflammation. These results indicate that the ectodomain shedding of LYVE-1 might be involved in promoting pathological lymphangiogenesis.Lymphatic vessels play crucial roles in maintaining tissue fluid homeostasis, immune surveillance, and fat absorption. Physiological lymphangiogenesis is regulated by several genes including Prox1 and vascular endothelial growth factor (VEGF)-C that induce the sprouting of lymphatic endothelial cells from embryonic veins during mammalian development (1, 2). Lymphatic endothelial cells express VEGF receptors (VEGFRs) 2 that represent a family of receptor tyrosine kinases. Among them, VEGFR-3 plays an essential role in promoting physiological lymphangiogenesis because VEGFR-3 shows a high affinity toward VEGF-C. In fact, several missense mutations are known among tyrosine kinase domains in Flt4/ VEGFR-3 that lead to the formation of Milroy disease, a congenital lymphedema due to an insufficient development of cutaneous lymphatic vessels. Thus, the VEGF-C/VEGFR-3 pathway plays a crucial role in promoting physiological and pathological lymphangiogenesis.VEGF-A, a specific ligand for VEGFR-1 and VEGFR-2, induces cutaneous angiogenesis in physiological and pathological conditions such as psoriasis (3). Targeted overexpression of mouse VEGF-A164 in the epidermis of transgenic mice leads to the formation of erythematous plaques resembling psoriasis (4), indicating that VEGF-A plays an important role in the pathogenesis of psoriasis. Our previous studies indicated that targeted overexpression of VEGF-A in mouse skin promotes the prominent enlargement of lymphatic vessels during acute inflammation by ultraviolet-B irradiation (5) and induces tumor-associated lymphangiogenesis as well as angiogenesis during multistep chemically induced skin carcinogenesis (6). Importantly, tumor lymphangiogenesis actively promotes enhanced metastasis to draining lymph nodes and beyond in VEGF-A transgenic mice as compared with wild-typ...

Inhibition of tumor formation and metastasis by a monoclonal antibody against lymphatic vessel endothelial hyaluronan receptor 1

“…Given that lymphangiogenesis occurs during wound healing, VEGF likely plays a role in the induction of cell migration in the presence of the supernatant from MDA‐231 cells. In this context, VEGF may induce shedding of the LYVE‐1 ectodomain, which promoted cell migration . The supernatant did not facilitate the migration of parental HEK293F cells, and the anti‐LYVE‐1 mAb did not affect the migration of HEK293 cells expressing LYVE‐1 in the absence of the MDA‐231 cell supernatant (data not shown).…”

“…Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE‐1) is a homolog of cluster of differentiation (CD) 44, a receptor for hyaluronan expressed on lymphatic endothelial cells (LEC), and is utilized as a lymphatic‐specific marker. LYVE‐1 binds to hyaluronan, and is involved in the migration of LEC, as well as in the transport of hyaluronan to the liver and regional LN . Furthermore, LYVE‐1 promotes hyaluronan‐induced lymphangiogenesis .…”

Homodimerization of the Lymph Vessel Endothelial Receptor LYVE-1 through a Redox-labile Disulfide Is Critical for Hyaluronan Binding in Lymphatic Endothelium

“…However, as LYVE-1 expressed mainly in lymphatics in the former tissues and blood vessels in the latter (4, 11), it is also likely that homodimerization is partly influenced by innate differences in receptor biosynthesis among lymphatic and vascular endothelia. It is also worth noting that the Cys-201 intermolecular disulfide lies upstream of the proteolytic cleavage site (Phe-226–Glu-229) by which soluble LYVE-1 ectodomains are shed by ADAM-17 in response to VEGF-A or phorbol ester (30). An important function may, therefore, be to preserve receptor bivalency and high affinity HA binding, once LYVE-1 is released from the plasma membrane.…”

LYVE1 and PROX1 in the reconstruction of hepatic sinusoids after partial hepatectomy in mice

“…These data suggest that VEGFA may have an essential role in mediating vasculogenesis during the early stage of liver regeneration. LYVE1 is a lymphatic vessel marker that is mainly present in the lymphatic endothelial cells surrounding great vessels in the liver tissues [4,21]. LYVE1 has also been detected in normal hepatic blood sinusoidal endothelial cells [19].…”

“…The glycoprotein lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1) is a widely accepted marker of lymphatic vessels [21] and has been observed in hepatic sinusoidal endothelial cells during the development of hepatic sinusoids [22]. Changes in the levels and distribution of LYVE1 in liver tissues during regeneration have not been fully elucidated.…”