Fig. 3.

¹²⁵I-Proticles are subjected to time- and concentration-dependent transcytosis across BCEC Transwell cultures. (A) Transwell cultures were incubated in the presence of ¹²⁵I-proticles (2.5 μg/ml; ON/protamine mass ratio of 1:2 and 1:5). At the indicated time points 100 μl of the basolateral medium was removed for counting and replaced by fresh medium. Results are mean±S.D. (n = 3). (B) Cells were incubated exactly as described in A. TEER was measured at the start and end (4 h) of the experiment. Results are shown as TEER ratios (TEER_end/TEER_start) and represent mean±S.D. (n = 4). (C) BCEC were cultured on polycarbonate filter inserts. After induction of tight junctions, ¹²⁵I-labeled proticles (ON/protamine mass ratio of 1:2 and 1:5) were added at indicated concentrations. After 4 h the basolateral medium was removed and counted on a γ-counter. Results are mean±S.D. (n = 3).