Horse podoplanin (horPDPN), a type I transmembrane sialoglycoprotein, is expressed on the podocytes of the kidneys, alveolar type I cells of the lungs, and lymphatic endothelial cells. PDPN is a platelet aggregation-inducing factor, and it primarily possesses three platelet aggregation-stimulating (PLAG) domains, that is, PLAG1, PLAG2, and PLAG3, at the N-terminus and several PLAG-like domains. In a previous study, we reported on a mouse anti-horPDPN monoclonal antibody (mAb) clone, PMab-202. Although the effectiveness of PMab-202 in flow cytometry and Western blotting is known, its exact binding epitope remains unknown to date. In this study, enzyme-linked immunosorbent assay and flow cytometry were used to identify the epitope of PMab-202. We found that the critical epitopes of PMab-202 include Lys64, Thr66, and Phe70 of horPDPN. We believe that our findings can be applied in the production of more functional anti-horPDPN mAbs.
Keywords: PDPN; PMab-202; epitope mapping; podoplanin.