Expression of E2 gene of bovine viral diarrhea virus in Pichia pastoris: A candidate antigen for indirect Dot ELISA

The results showed that the expressed products in the culture medium resulted in single band of 44 kDa by SDS-PAGE and Western blotting. The results of the immunogenicity assay indicated that the protein E2 expressed in P. pastoris could induce the experimental animals of the rabbit to produce BVDV specific antibodies. The results of the indirect Dot-ELISA showed that the optimal coating concentration of the E2 recombinant protein was 2.0 μg/mL, the bovine serum dilution was 1:100, the optimal concentration of HRP-labeled rabbit anti-bovine antibody IgG was 1:500, and the optimal blocking reagent was 3% glutin-TBS and blocking for 45 min. The indirect Dot-ELISA showed 96.7%, 92.5% and 95% in the terms of specificity, sensitivity and accuracy compared to the IDEXX ELISA test kit. The indirect Dot-ELISA using the E2 recombinant protein can be used for the detection of antibody against the BVDV and could be considered in the surveillance programs.