Drug resistance is a phenomenon mediated by up-regulation of a family of transmembrane ATP Binding Cassette (ABC) transporter proteins. Overexpression of ABC transporter proteins accelerates removal of toxic agents from the cell, for example the efflux of chemotherapeutic agents from tumor cells, or of antibiotics from resistant strains of bacteria.

The EFLUXX-ID™ Multidrug Resistance Assay Kits allow for functional detection of all three clinically relevant ABC transporter proteins: MDR1 (p-glycoprotein), MRP1/2, and BCRP.

• Comprehensive efflux detection assay for three major types of ABC transporters.
• Detects BCRP activity not detected with Calcein AM.
• Inhibitors included for profiling of specific pumps involved in drug resistance.
• Two dye formats allows multiplexing with GFP-expressing cell lines or other CELLestial dyes.

The EFLUXX-ID™ assay uses a hydrophobic, non-fluorescent compound that readily penetrates the cell membrane, where it is hydrolyzed to a hydrophilic fluorescent dye by intracellular esterases. The resulting fluorescent dye is trapped inside the cell unless it is actively pumped out by ABC transporter protein activity. Thus, cells exhibiting drug resistance will have diminished fluorescence.