Fig. 5. Uptake measurement and localization of FITC-albumin in RF/6A endothelial cells. (A-D) Fluorescence microscopy of FITC-albumin (A,D; green fluorescence) in RF/6A endothelial cells after 60 minutes of incubation in the presence of FITC-albumin on coverslips followed by washing off excess FITC-albumin and staining for F-actin with phalloidin (B,D; red fluorescence). Cellular nuclei are highlighted by DAPI staining (C,D; blue fluorescence). The image in D represents the merge images of A-C. Scale bar: 20 µm. (E) FITC-albumin intracellular uptake by RF/6A cells as a function of time. The data shown in E are expressed as the mean of pmol per µg of protein ± s.e.m.