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Updated: May 27, 2026
Determination of High-affinity Antibody-antigen Binding Kinetics Using Four Biosensor Platforms
Published on: April 17, 2017
Antibody binding shift assay for rapid screening of drug interactions with the human ABCG2 multidrug transporter
Ágnes Telbisz1, Csilla Hegedüs, Csilla Özvegy-Laczka
1Membrane Research Group of Hungarian Academy of Sciences, Department of Biophysics, Semmelweis University and National Blood Center, Diószegi u 64, H-1113 Budapest, Hungary.
Abstract:
The ABCG2 multidrug transporter protein has been identified as a key player in cancer drug resistance and xenobiotic elimination, as its actively transported substrates include anticancer drugs, intermediates of heme metabolism, xenobiotics, and also drug conjugates. Several transported substrates at higher concentrations, and some anticancer agents even at low concentrations directly inhibit the ABCG2 transporter, thus it is difficult to provide estimation for pharmacologically important ABCG2-dependent interactions. In addition, as documented here, in mutant variants of the transporter, inhibitors of the wild-type ABCG2 may become actively transported substrates. In this paper we describe a rapid in vitro assay to identify transport modulation by measuring the cell surface interaction of a conformation sensitive monoclonal antibody (5D3) with ABCG2 in intact cells. As documented, in conjunction with membrane ATPase, transport and cytotoxicity measurements, this assay provides a reliable estimate of concentration-dependent modulation of ABCG2 by newly emerging pharmacophores. A high-throughput, 96-well plate assay platform is also provided.
Insights
This study introduces a new assay to measure how compounds affect the ABCG2 transporter, crucial for cancer drug resistance. The method helps predict drug interactions and develop new cancer therapies.
Area of Science:
- Biochemistry
- Pharmacology
- Molecular Biology
Background:
- The ABCG2 transporter is vital in cancer drug resistance and eliminating foreign substances.
- Understanding ABCG2 interactions is complex due to substrate inhibition and altered function in mutants.
Purpose of the Study:
- To develop a rapid in vitro assay for assessing ABCG2 transporter modulation.
- To provide a reliable method for evaluating new pharmacophores impacting ABCG2.
Main Methods:
- Utilized a conformation-sensitive monoclonal antibody (5D3) to measure cell surface interaction with ABCG2.
- Integrated membrane ATPase, transport, and cytotoxicity assays.
- Developed a high-throughput, 96-well plate assay platform.
Main Results:
- The assay accurately estimates concentration-dependent modulation of ABCG2.
- Demonstrated the utility of the assay for newly emerging pharmacophores.
- Provided a platform for high-throughput screening.
Conclusions:
- The developed assay offers a reliable and efficient method for studying ABCG2 transporter modulation.
- This tool aids in predicting drug interactions and developing novel cancer therapeutics.
