Figure 2. Analysis of LEP503 promoter specificity. A: The expression of EGFP driven by lenti-LEP503-HSV-tk-EGFP vector in HLECs, RPECs, and ASFCs at 72 h after being infected. B: The expression of EGFP driven by lenti-CMV-HSV-tk-EGFP vector in HLECs, RPECs, and ASFCs at 72 h after being infected. Magnification: 40×; Green: EGFP, Blue: DAPI staining. C: Flow cytometry evaluation of the expression of EGFP driven by lenti-LEP503-HSV-tk-EGFP and lenti-CMV-HSV-tk-EGFP vectors in HLECs, RPECs, and ASFCs at 48 h after being infected. D: western blotting assessment of the expression of EGFP driven by lenti-LEP503-HSV-tk-EGFP vector at 24, 48, and 72 h after being infected, and by lenti-CMV-HSV-tk-EGFP vector 72 h after being infected in HLECs, RPECs, and ASFCs. E: Semi-quantitative analysis of the western blotting results. The intensities of HSV-tk mRNA were normalized to ACTB (n=3).