FIG. 2.
In vitro gene transfer to primary hepatocytes with adenovirus vectors containing chimeric fiber and inhibition of gene transfer by recombinant fiber knob or penton base protein. (A) CAR, αvβ3-type, and αvβ5-type integrin expression (heavy lines) in human primary hepatocytes was determined by flow cytometric analysis. The thin lines show the results for the corresponding negative controls. (B) The primary hepatocytes were incubated with the adenovirus vectors at a multiplicity of infection (MOI) of either 100 or 1,000 particles/cell for 1 h and then assayed for β-galactosidase activity at 30 h postinfection. RLU, relative light units. (C) The specificity of gene delivery to the primary hepatocytes of adenovirus vectors containing chimeric fiber (1,000 particles/cell) was examined by competition with recombinant Ad5 fiber (25 μg/ml) or Ad2 penton base (50 μg/ml) protein. After competition for 30 min at 4°C, the cells were washed with Dulbecco's modified Eagle's medium and infected with the adenovirus vectors for 15 min at room temperature. LacZ activity at 18 h was expressed as the percentage of ithe activity determined in the absence of the competing protein. The results represent means ± standard deviation of triplicate determinations.