Screening Compounds with a Novel High-Throughput ABCB1-Mediated Efflux Assay Identifies Drugs with Known Therapeutic Targets at Risk for Multidrug Resistance Interference
Figure 1
Cell imaging-based ABCB1-mediated calcein AM efflux by KB-V1 and KB-3-1 cells.
A. Time-and dose-dependent fluorescent calcein accumulation in KB-V1 cells. Various concentrations of calcein AM were added to KB-V1 cells. The phase-contrast and fluorescent images were taken at the indicated times by the IncuCyteTMFLR. The mean fluorescence intensities were obtained from the IncuCyteTMFLR and plotted. Data presented are mean ± SD (n = 3). B. KB-V1 cells overexpress ABCB1. Particulate fractions of KB-3-1 and KB-V1 cells were subjected to western blotting with an anti-ABCB1 antibody. For the flow cytometry efflux assay, KB-V1 cells were treated with 5 µM of each inhibitor followed by 1 µM calcein AM. Red is for calcein AM; green is for XR9576; blue is for FTC; orange is for MK-571. C. XR9576 enhances calcein fluorescence in KB-V1 cells but not KB-3-1 cells. KB-V1 and KB-3-1 cells were treated with XR9576 before addition of calcein AM (1 µM). The phase and fluorescent images were taken 1 hour later by the IncuCyteTMFLR. The mean fluorescence intensities were obtained from the IncuCyteTMFLR. Data presented are mean ± SD (n = 3). ** indicates p<0.05.