Comparison of susceptibilities of BmN-SWU1 and BmN-SWU2 ovarian cell lines to BmNPV infection.

<p>(A) Schematic diagram illustrating construction of donor plasmids and generation of recombinant BmNPV vA4^prm-VP39-EGFP, which contains the <i>EGFP</i> fluorescence marker gene driven by the silkworm <i>actinA4</i> promoter. (B) Fluorescence microscopy showing the progression of infection in both cells lines infected with vA4^rpm-VP39-EGFP (MOI = 2 or 20) at 24, 48 and 72 h p.i. (C) BmNPV infection efficiencies (EGFP positive, EGFP+) in BmN-SWU1 and BmN-SWU2 cells were determined by counting fluorescent cells in five different fields of view. Three independent experiments were carried out with three replicates each. Data are presented as means ± SD (n = 3). Statistically significant differences: **P<0.01. (D) Western blot analysis of silkworm ovarian cells lysed at indicated times after vA4^rpm-VP39-EGFP infection (MOI = 20) using an α-EGFP antibody.