FIG. 2.

Coagulation factors promote efficient Ad5 binding and gene delivery to epithelial cells in a dose-dependent manner. (A) ³⁵S-labeled CsCl-purified Ad5 virions were preincubated with or without increasing concentrations of FIX or FX and then incubated with A549 or HCE cells in suspension on ice for one hour. Unbound virions were removed by washing, and the cell-associated radioactivity was measured in a scintillation counter. (B) GFP-expressing, CsCl-purified Ad5 viruses were preincubated with or without increasing concentrations of FIX or FX and then incubated with adherent A549 or HCE cells on ice for one hour. Unbound viruses were removed by washing. The cells were incubated at 37°C for another forty-four hours. Next, GFP-expressing cells were quantified by flow cytometry. The control binding level corresponds to the y axis value of 1. Values are means ± SD. *, P of <0.05 versus control; **, P of <0.01 versus control.