RESUMEN
To prepare the polyclonal antibody against the 3D polymerase of foot and mouth disease virus (FMDV), the 3D polymerase gene of this virus was amplified by PCR and doubly digested with BamH I and Nde I. Then, it were cloned into expression vector pET-30a(+) to obtain the recombinant plasmid pET-3D and this plasmid was transformed to E.coli BL21(DE3) with induction by IPTG.The target protein was identified and purified with SDS+PAGE, and the inclusion bodies were extracted. The purified target protein was used as antigen to immunize New Zealand rabbits to prepare the polyclonal antibody against 3D polymerase of FMDV, which was then characterized by indirect ELISA and Western blotting. As demonstrated by SDS-PAGE, the target protein with a molecular weight at 46 ku was expressed. The polyclonal antibody showed high affinity and obvious specificity and its titer was above 1:8 000. This polyclonal antibody may lay a foundation for the further studies on the biological functions and epitopes of the 3D polymerase of FMDV.