Recombinant Human Endocan Protein

Endocan, also known as endothelial-cell specific molecule-1 (ESM-1), is a secreted cysteine-rich dermatan sulfate (DS) proteoglycan primarily expressed by endothelial cells within the vascular capillary network in kidney and in the alveolar walls of the lung (1). Endocan expression has also been detected in different epithelia and in adipocytes (2, 3). The expression of endocan is upregulated by TNF alpha, IL-1 beta or lipopolysaccharide and down-regulated by IFN gamma (1). The human Endocan gene encodes a 184 amino acid (aa) residues precursor protein with a 19 aa hydrophobic signal peptide and a 165 aa mature region with 18 Cysteine residues (1). The DS chain is covalently attached to serine 137 (4). Endocan has been shown to bind CD11a/CD18 integrin (also known as lymphocyte function-associated antigen-1, LFA-1) on human lymphocytes, monocytes and Jurkat cells, inhibiting its binding to ICAM-1 and reducing LFA-1-mediated leukocyte activation (5). Endocan binds via its DS chain to hepatocyte growth factor (HGF) to enhance HGF mitogenic activity (3, 6). Genetically engineered cells overexpressing endocan has been shown to induce tumor formation, suggesting that Endocan may be involved in the pathophysiology of tumor growth in vivo (3, 6). Circulating Endocan can be detected in the serum from healthy subjects. In patients with lung cancer or acute and severe sepsis, elevated Endocan concentrations have been reported (2, 6).