Preparation of Anti-Human Podoplanin Monoclonal Antibody and its application in Immunohistochemical Diagnosis

Podoplanin (PDPN), a 38 kDa transmembrane sialoglycoprotein from human, is expressed in lymphatic endothelial cells but not in vascular endothelial cells, and has been considered as a specific marker of lymph. In this study, the gene encoding the extracellular part of PDPN (ePDPN) was synthesized and used to expressed fusion protein ePDPN-His and GST-ePDPN, respectively, in E.coli. The purified GST-ePDPN fusion protein was mixed with QuickAntibody-Mouse5W adjuvant to immune mice, and the antiserum titer was determined by indirect ELISA. A stable cell line named 5B3 generating anti-PDPN monoclonal antibody (mAb) was obtained by hybridoma technology. The isotype of 5B3 cell line was IgG2b, and the chromosome number was 102 ± 4. The 5B3 mAb was purified successfully from ascites fluid through Protein G column, and its affinity constant was 2.94 × 108 L/mol. Besides, excellent specificity of the 5B3 mAb was further demonstrated in ELISA, western blot and immunohistochemistry experiments, suggesting that 5B3 mAb displays similar application value to D2-40, a commercial available antibody. Hence, the current study provides conclusive guidelines for preparation of other mAbs and their applications in immunohistochemistry diagnosis.