Adenoviral gene transduction efficiencies (AGTEs) in each culture condition. Cells that had been cultured under either serum-minus or serum-plus conditions were infected for 48 h with Ad.CMV-EGFP at MOI of 0 (none), 0.1, 1, 10, or 30. Subsequently, fluorescence-microscopic analysis (A) and flow-cytometric analysis (B) were performed to assess EGFP-expressing cells. (A) Representative images of phase-contrast (upper) and the fluorescence (lower) microscopy are shown at 50× (left) and 200× (right) magnification. No difference in AGTEs between the two groups was apparent.