Figure 5.

Intracellular uptake of Taxol is cell and efflux-dependent. A) WB data are shown for n=2 separate experiments targeting P-gp expression in response to control or Taxol-treated cells. Mean intensity (normalized to β-actin) ± SEM is shown. B) Flow cytometry data for P-gp expression using standard and recombinant (rP-gp) form of antibody. C) Mean fluorescent intensity (MFI) of intracellular 488-Taxol, as measured by flow cytometry. Mean intensity ± SEM is shown. D) Normalized MFI of intracellular 488-Taxol is shown for control (488-Tax) and cells pre-treated with inhibitors (Verapamil and Elacridar). Shown are box-plots (with SE and SD outer bars) overlaid on data from n=3 samples. E) Schematic of pre-treatment with P-gp inhibitor in the TS-MVN system. F) P-gp inhibition has no effect on diffusive permeability measurements made using 40kDa dextran in the MVN system (without TS). Shown are box-plots overlaid onto raw data. G) Normalized intra-tumor (TS) 488-Taxol intensity for control and P-gp-inhibited TS-MVN samples. Significance is indicated for t-tests, with *P<0.05, **P<0.01.