FIG. 12.

Stability of vector. (A) Efficiency of gene transfer to CFT1 cells mediated by amphotropic (Ampho) and VSV-G-pseudotyped lacZ vectors that had been incubated at 37°C in the presence of Polybrene (8 μg/ml) for up to 8 h prior to infection. (B) Efficiency of gene transfer to CFT1 cells with initial application of vector and subsequent transfer of vector to naive CFT1 cells. In each case, vector was incubated with cells for 2 h at 37°C. (C) Efficiency of gene transfer to CFT1 cells following incubation of vector with well-differentiated cells for 2 h at 37°C in the presence of 8 μg of polybrene per ml (Transfer) compared to infection of cells with vector from the same preparation that had not been incubated with vector (Naive).