TABLE 1.

Lamivudine transport across monolayers of MDCK parent cells and human MDR1-, BCRP-, and MRP2 ABC transporter-expressing MDCK cells^a

Cell line	BA/AB rt
MDCK parent	0.923 ± 0.195
MDCK-MDR1	0.930 ± 0.140
MDCK-BCRP	1.25 ± 0.0277*
MDCK-MRP2	1.03 ± 0.131

^aCells were seeded on Transwell semipermeable supports and grown as monolayers, dividing, similarly to a polarized trophoblast layer, the basal compartment (corresponding to fetal side) and apical compartments (corresponding to maternal compartment). The basal-to-apical/apical-to-basal transport ratios (BA/AB r_t) for translocation of lamivudine (8 nM) across monolayers of ABC transporter-expressing cells and parent MDCK cells after 6 h are shown. Data are presented as means ± SD of ratios obtained in at least four independent experiments (n ≥ 4). Student´s t test was employed to compare the ratios of particular ABC transporter-expressing cells to the respective ratio in MDCK parent control cells, and results were considered statistically significant at P ≤ 0.05 (*).