Cellular uptake of fluorescence signal in Caco–2 cells incubated with fluorescence labeled GP.

<p>Flow cyctometry (A+C) and confocal microscopy (B+D) of Caco–2 cells after 3 h incubation with P31–43 (A+B) and P56–68 (C+D) at 37°C and 4°C. Flow cyctometry (E+G) and confocal microscopy (F+H) of Caco–2 cells after 24 h incubation with P31–43 (E+F) and P56–68 (G+H) with (+MβCD) and without methyl-β-cyclodextrin (−MβCD). To detect autofluorescence of Caco–2 cells, non-treated cells were analysed and used as controls. Mean fluorescence intensity (MFI) of cells analysed by flow cytometry (I-K): Comparison of MFI of Caco–2 cells after 3 h and 24 h incubation with P31–43 and P56–68 (I). Comparison of MFI of Caco–2 cells after 3 h incubation with P31–43 and P56–68 at 37°C and 4°C (J). Comparison of MFI of Caco–2 cells after 24 h incubation with P31–43 and P56–68 with and without MβCD (K). Results are shown as mean ± SD; *p<0.05, ***p<0.005.