P-gp (MDR1) Transporter Assay (ABCB1)

The P-gp transporter is an efflux transporter that is encoded by the ABCB1 gene. P-gp is also known as P-glycoprotein and the Multi-Drug Resistance transporter 1 (MDR1). P-gp (MDR1) is expressed in many tissues of the body including in the kidney on the apical side of the intestinal lumen, the apical side of the bile canaliculus in liver hepatocytes, the apical membrane of proximal tubule epithelial cells and the apical side of the capillaries in the blood brain barrier (BBB). P-gp (MDR1) serves to limit the absorption of substrates, protect them from entering the brain and also to mediate their renal and hepatic elimination.

Optivia offers P-gp (MDR1) substrate and inhibition assays for transport in polarized mammalian cells. We offer a wide range of studies including single concentration screens up to full kinetic studies to determine the IC50 for P-gp (MDR1) inhibitors as well as Vmax and Km values for P-gp (MDR1) substrates.

P-gp (MDR1) Transporter Assay

Relevance – FDA & EMA DDI guidances; intestinal and BBB efflux, biliary secretion, renal tubular secretion, drug resistance Single or Multi-Transporter Model – Single
Transporter Type – Efflux Cell Model – MDCK-II, Caco-2
Assay Type – Bi-directional Exactly Matched Control Cells – n/a
Species – Human Probe Substrate – digoxin, quinidine
Subcellular Localization in Assay Model – Apical Inhibition Positive Control – verapamil, elacridar