Development Of Monoclonal Antibodies Against Matrix Protein Of PRRSV NVDC-JXA1 Strain And Antigens Of PRRSV Quickly Detected In Froze Histological Section By An Immunofluorescence Assay

Porcine reproductive and respiratory syndrome virus(PRRSV)was the causative agent of PRRS,which caused reproductive failure in sows and respiratory problems in piglets.In recent,some pig farms in China occurred swine high fever in summer .In 2007,Chinese Agriculture Department announce that PRRSV was the main angen in high fever. At present, It has been one of most serious virulent epidemic diseases which.harm our country pig-breeding industry .In this study,6~8 week-old BALB/c mice were immunized conventionally with the purified virions of Porcine reproductive and respiratory syndrome virus(PRRSV) NVDC-JXA1 strain.By using the hybridoma technique, On the third day after the final immunization, spleen cells of mice fused with myeloma cells SP2/0 were filtered by culturing selectively,The two monoclonal antibodies (McAbs) were obtained by Enzyme-linked Immunosorbent Assay (ELISA) test and Indirect immunofluorescent Assay (IFA)and were named as 1D12,5H5.The subtypes of the two McAbs was identified as IgG2b,IgM respectively,Kappa light chain.the ELISA titers of culture supernatants and ascites were 1:103～1:104 and 1:105～1:107respectively.The two McAbs reacted specifically with PRRSV NVDC-JXA1 and PRRSV VR-2332 but not with CSFV,PPV,PCV,PRV,JEV.The two McAbs reacted to matrix protein of PRRSV by western-blot.An immunofluorescence assay(IFA) mediated by monoclonal antibody 1D12 was developed to detect antigen of Porcine reproductive and respiratory syndrome virus in froze histological section directly.The tissues of pigs infected with CSFV,PPV,PCV,PRV,JEV had not shown specical immunofluorescence signs.Fourteen days post infection, specical immunofluorescence signs could be detected in lung,the hilarl node,spleen, tonsil,kidney and brain of the 28-dap-old piglets artificially infected with PRRS NVDC-JXA1 strain by the method.The positive percentage(62.5%) of detecting field suspicious cases was higher than the percentage (31.25%) of virus isolation and coincidence ratio was 100%.The results show that IFA is a specific, sensitive and visual staining method.It can be applied to diagnose PRRS,to detect the distribution of PRRSV antigen in tissues the infected pigs.