Monoclonal antibody LpMab17 recognizes human Podoplanin (PDPN; agrrus). Podoplanin is a small type_I transmembrane sialoglycoprotein expressed on a broad range of cell types and involved in platelet aggregation and tumor metastasis. The 36 kDa protein was initially identified as a biomarker of lympatic endothelium, alveolar epithelium and glomerular podocytes. Expression has also been found in many tumors. However the functional role of PDPN is still poorly understood. Podoplanin consists of an extracellular domain, transmembrane domain and a cytoplasmic tail. In its extracellular domain it possesses a platelet aggregation stimulating (PLAG) domain. Podoplanin has got three PLAG domains of which PLAG3 is critical for binding with C-type lectin receptor-2 (CLEC-2). This PDPN specific receptor mediates platelet aggregation. This interaction is required to initiate and maintain separation of blood and lymphatic vessels and can be critical in process of cancer metastasis. This may lead to PDPN as possible therapeutic target. Antibody LpMab-17 recognizes a non-PLAg domain (Gly77-Asp82). Although PDPN is quite conserved between species, LpMab17 does not bind monkey PDPN.