Production and Characterization of Monoclonal Antibodies against Porcine reproductive and respiratory syndrome virus

【Objective】 The paper was to obtain monoclonal antibodies against PRRSV for further study of its structure and function.【Method】 The antigen of PRRSV FZ strain was purified by differential centrifugation and discontinuous sucrose density gradient centrifugation.The spleen cells of Balb/c mice immunized with purified viral antigen were fused with SP2/0 myeloma cells.Hybridoma cell lines secreting monoclonal antibodies against PRRSV were screened by using indirect enzyme linked immunosorbent assay(ELISA) and the subcloning approach.The specificities of these monoclonal antibodies were determined by ELISA,Western blotting and Immunofluorescecence assay.【Result】 Three hybridoma cell lines developed could steadily secure specific monoclonal antibodies(McAbs) against PRRSV-FZ and were designated A61,B47 and C65,respectively.The isotyping analysis results showed that both A61 and C65 belonged to IgG1,and B47 belonged to IgG3.These McAbs could bind to the antigen of PRRSV FZ in ELISA,IFA and western-blot analysis.Their ELISA titers of the supernatant ranged from 27 to 28 and that of ascites fluid was 105-106.These McAbs were highly specific and had no cross-reactivity with Marc-145 cells,Porcine parvovirus(PPV) and Porcine circovirus Type 2(PCV2).Western blot analysis confirmed that three McAbs could recognize 26 Ku structure protein(GP5 protein).【Conclusion】 3 Monoclonal antibodies of high specificity against GP5 protein were prepared successfully,which laid a foundation for the further study on PRRSV quick-diagnosis.