FIG. 5.

(A) Effect of DGD and DCPD antibodies on DGD binding to a truncated pre-S peptide. Duck liver lysate was incubated with pre-S peptide 80-102 immobilized on beads via the GST tag. DGD or DCPD antibodies (Ab) in various dilutions were present during the incubation, and DGD retained on the beads was detected by Western blot. (B) Antibody binding to duck hepatocytes and internalization. PDH were incubated with a 1:20 dilution of preimmune or immune serum for 1, 2, or 3 days, washed, and harvested with (+) or without (−) trypsin treatment. Cell-associated immunoglobulin was detected. (C) Specificity of antibodies attached to PDH. PDH were metabolically labeled and subsequently incubated for 6, 24, or 48 h with or without a 1:20 dilution of DGD antiserum. Cells were harvested, and the cell lysate was incubated with 30 μl of protein A beads. Bound proteins were revealed by SDS-PAGE and fluorography. The 120-kDa DGD protein was pulled down only in cells preincubated with DGD immune serum.