Analysis of EGFP expression in infected HEK 293 cells. Cells were cultured in 10% FBS and were infected with AAV-β2AR/EGFP and screened for EGFP expression as a surrogate marker of β2AR expression efficiency. Using epifluorescence microscopy to compare phase contrast (A) and green fluorescence (B), EGFP expression was observed in ~40% of cells present, as seen in this representative image. This experiment was performed 5 times with similar results. Scale bar, 10 μM.