MDCKII-MDR1

About the Assay

The MDCKII–MDR1 (Madin–Darby canine kidney II) is a canine epithelial cell line stably transfected with human ATP binding cassette transporter protein (MDR1/ABCB1). MDCKII-MDR1 cells form tight, polarized monolayers suitable for drug transport assays and enable exploration of specific interactions with human MDR1. It has been reported that transfection of wild type MDCKII cells with human transporters results in a knock down of endogenous (canine) transporters including those responsible for efflux.

Drug transport is measured bi-directionally, apical-to-basolateral (AtoB) and basolateral-to-apical (BtoA), which allows for the rate of permeability to be determined and for the identification of MDR1 mediated efflux substrates.

Given lipid bilayers are universally conserved across all species, MDCKII-MDR1cells represent a useful and human relevant system for bidirectional transport studies which enable the identification of passive and active transport processes and can help predict the oral absorption and CNS penetrance of new chemical entities.

Protocol Summary

Sygnature discovery use pre‑plated MDCKII‑MDR1 cells (MedTech Barcelona) to assess compound permeability and efflux potential in hanging insert format.

Compound Selection

A diverse set of compounds was selected to span a range of intrinsic permeabilities and to include both efflux and non‑efflux substrates.

Validation Results

Figure 1  Apparent permeability coefficient (Papp) results for test compounds evaluated in Sygnature Discovery’s MDCKII MDR1 assay with HBSS pH 7.4/7.4 buffer. Each bar represents the mean +/- SD Papp fromindividual experiments, A-B (top) and B-A (bottom), of validation compounds in order from lowest to highest.

Figure 2. Efflux ratio calculated for test compounds evaluated in Sygnature Discovery’s MDCKII MDR1 assay with HBSS pH 7.4/7.4 buffer. The dotted line indicates the threshold of ER = 2Results are presented as mean +/- SD

Figure 3. Efflux observed for test compounds evaluated in Sygnature Discovery’s MDCKII MDR1 assay with HBSS pH 7.4/7.4 buffer. The dotted line indicates the threshold of ER = 2. Results are presented as mean +/- SD

References

Hubatsch, I., Ragnarsson, E. & Artursson, P. Determination of drug permeability and prediction of drug absorption in Caco-2 monolayers. Nat Protoc 2, 2111–2119 (2007).