Influence of MRP8/MRP14 on transendothelial resistance and permeability. Filter-grown HMEC monolayers were treated for 16 hours with different concentrations of MRP8/MRP14 (A-B) or with 200 μg/mL MRP8/MRP14 (MRP), together with 10 μg/mL polymyxin B (PMX), isotype control antibody (control ab), anti-MRP8 and anti-MRP14 antibodies (anti-MRP ab), or MRP8/MRP14 preabsorbed by isotype control antibody or anti-MRP8 and anti-MRP14 antibodies (C). Subsequently, the TER of the monolayer, expressed as ohm/cm² (A,C), and the permeability, expressed as percentage of control (B), were determined. All data are presented as mean ± SD of 3 experiments (P < .05). Asterisks represent significant differences to control samples with P < .05.