Figure 1.

Expression of BVDV E2 protein and identification of its immunogenicity. (A) SDS-PAGE analysis of rpE2, M, protein marker; IP, culture medium supernatant after transfection; FT, flow-through after incubation with Ni²⁺ NTA affinity column; E2-1, E2-2, E2-3, and E2-4, purified BVDV E2 proteins. (B) Western blotting analysis of the purified rpE2 with various antibodies. (a) Incubated with His-tag mouse mAb; (b) Incubated with BVDV antiserum; (c) Incubated with bovine viral diarrhea virus type 1&2 (BVDV-1&2) mAb E2 gp53 IgG2b isotype. M, protein marker; lane 1, purified BVDV E2 protein with His tag; lane 2, cell culture medium. (C) ELISA and virus neutralization test analysis of anti-BVDV E2 serum.