FIG. 1.

Transduction on FN is more efficient in the absence of PB. NIH 3T3 cells were added to 96-well FN-coated plates or TCP at 5,000 cells/well. The next day, target cells were incubated (∼12 h) with amphotropic retrovirus stock in the presence or absence of PB. The transduction efficiency was quantified after the target cells reached confluence by measuring the activity of β-galactosidase (βGal). Values are means ± standard deviations of duplicate samples in a representative experiment. The asterisk denotes a very small value (close to zero).