Construction And Application Of Foot-and-mouth Disease Antigen Epitope Marker Vaccine Candidate

With the progress in studying gene structure and function of foot and mouthdisease virus (FMDV), FMDV can express exogenous genes in different sites.Through transforming and modifying FMDV can achieve different app licationpurposes such as improving virus titer, introducing tag, improving immune responses,and reducing pathogenicity.The purpose of this experiment is to construct a FMDV vaccine which candistinguish different kinds of antibody between infects and vaccinations. To preparefoot-and mouth-disease markered vaccine strain with deletion of an antigen epitope,an infectious clone of pAsia1-FMDV was used to constucte the markered vaccinestrain with deletion of an antigen epitope. An antigen epitope in3D was selected astarget epitope and the key amino acid H and N in27thand31thsite of the targetepitope was mutated into Y and R, respectively. Then, the3D gene was replaced intothe pAsia1-FMDV and resulting in the plasmid pAsia1-FMDV-m3D. To get therecombinant virus, the plasmid pAsia1-FMDV-m3D transfected into BHK-21cellsand passaged, cytopathic effect (CPES) was observed. And the biologicalcharacteristics between recombiant virus strain was compared with parental virusstrain, the results shown that the biological characteristics are similar.Animals can quickly produce specific anti-viral antibodies after infected therecombinant virus. Using indirect immunofluorescent assay in the cell can be detectedviral proteins.In order to determine whether the epitope in the recombiant virus strainwere missing, the peptides of the epitope were synthesized based on mutant andparental virus3D gene sequence differences. The results indicated that the two virusstrains could be distinguished by western-blot with synthetic peptide. To identifywestern-blot with synthetic peptide whether could be distinguishes the two virus.Theantibodies of recombinant virus can be distinguished by western blot experiments.