FIG 4.

Recombinant BA strain binding to cells in vitro. (A and B) BEAS-2B cells were inoculated with the indicated viruses at an MOI of 1.0, and virus was allowed to adsorb to cells at 4°C. Inoculum was removed, and cells were washed three times in cold PBS to remove unbound virus. Cells were lysed, and lysates, along with an aliquot of original inoculum, was subjected to SDS-PAGE and Western blotting with an anti-N monoclonal antibody. GAPDH was also probed as a loading control. (A) Representative Western blots of binding assay. (B) Combination of densitometry results of the three experiments illustrated in panel A. The amount of bound N was normalized to N in the inoculum as well as GAPDH prior to comparison between groups. *, P < 0.05 (by paired t test). (C) Representative Western blots from binding assay performed with CHO-K1 and pgsD-677 cell lines. For experiments in CHO-K1 and pgsD-677 cells, sucrose-purified virus stocks were used, and the infection inoculum was normalized based on N protein levels in purified stocks. (D) Combination of densitometry results of the three experiments illustrated in panel C. *, P < 0.05 (by paired t test). ns, not significant.