A-D: Relative expression of the Abc and Slc transporters is shown as mean ± SEM in isolated CP, primary CP cells and in the immortalized cell lines TR-CSFB and Z310. Cq (quantification cycle) values for each gene were normalized to Cq values of the reference gene Gapdh. Slco1a5 (Oatp1a5) is the most highly expressed gene in CP and shown in the separate graph. Abcb1 (P-gp), Abcc1 (Mrp1) and Abcc4 (Mrp4) are highly expressed in all cells as well as in the tissue control, while Slc genes are neither expressed in primary cells nor in the cell lines. E: Comparison of transporter expression in the cells with expression in CP tissue, which was set to 1. Most transporters are down-regulated in the cells. Abcc2 (Mrp2) is only expressed in TR-CSFB cells while primary cells express more Abcc5 (Mrp5) and Abcb1 (P-gp) than freshly isolated CP. Abcc3 (Mrp3) and Abcg2 (Bcrp), which seem to be up-regulated are hardly expressed as can be seen in B-D.