Abstract:

The aim of this study was to produce the antibody against the protein of open reading frame 3 (ORF3) of porcine circovirus type 2 (PCV2), and lay foundation for research on ORF3 function. The ORF3 gene of PCV2 was amplified by PCR method, and the PCR product was digested by restriction enzyme EcoR I and Xho I. Meanwhile, the eukaryotic expression vector pCDNA3.1 (+) was digested by EcoR I and Xho I too. Then, the two expected products digested were ligated, and the transformation in the competent cells of E.coli DH5? was conducted. The results of colony PCR and sequence analysis showed that the recombinant expression vector pCDNA3.1-PCV2 ORF3 was constructed successfully. Thereafter, several BALB/c mice were inoculated with the recombinant plasmid constructed, and the specificity and titer of the antibody to PCV2 ORF3 were detected by immunofluorescence assay (IFA). The IFA results demonstrated that the sera collected from the mice inoculated with the recombinant plasmid PCV2 ORF3 were the antibodies specific to PCV2 ORF3. Also, the IFA results showed that the antibody titer of PCV2 ORF3 in the sera of mice were all more than 1:25 after 4 times inoculation, which indicated that the antibodies against PCV2 ORF3 with relatively high titer was successfully produced. The research results revealed that the antibody to PCV2 ORF3 could be produced quickly and simply by vaccination of plasmid DNA, and this provided a new effective way to the production of the antibodies to PCV2 ORF3.