• Product name
    MDR Assay Kit (Fluorometric)
    See all MDR kits
  • Sample type
    Adherent cells, Suspension cells
  • Assay type
  • Assay time
    1h 0m
  • Species reactivity
    Reacts with: Other species, Mammals
  • Product overview

    Multi drug resistance (MDR) is a major factor in the failure of many forms of chemotherapy. In the past few years it has become widely accepted that the resistance to chemotherapy correlates with the overexpression of at least two ATP dependent drug efflux pumps. These cell membrane proteins, called P-glycoprotein (Pgp, MDR1), and multidrug resistance associated protein (MRP1) are members of the ABC transporter family. Abcam's Fluorimetric MDR Assay Kits use a fluorescent MDR indicator for assaying these two MDR pump activities. This hydrophobic fluorescent dye molecule rapidly penetrates cell membranes and becomes trapped in cells. Following a short incubation, the intracellular free dye concentration can increase significantly. In the MDR1 and/or MRP1-expressing cells this dye is extruded by the MDR transporters, thus decreasing the cellular fluorescence intensity. However, when its extrusion is blocked by an agent that interferes with the MDR1 and/or MRP1 pump-activity, its cellular fluorescence intensity increases significantly. Abcam's Fluorimetric MDR Assay Kits are ideal for high throughput screening of MDR pump inhibitors or identifying the cells that have high level of MDR pump activities.

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  • Notes

    Store ab112142 dessicated.



  • Effect of Cyclosporin A on the inhibition of P-gp pump in MCF7/ADR cells. The increased concentration of Cyclosporin A resulted in an increase in fluorescence signal caused by the inhibition of P-gp pump which enhanced the intracellular accumulation of MDR indicator dye. The EC50 = 2.4 µM (measured with the kit) is similar to the value reported in the literature.



This product has been referenced in:
  • Wang X  et al. Extracellular ATP, as an energy and phosphorylating molecule, induces different types of drug resistances in cancer cells through ATP internalization and intracellular ATP level increase. Oncotarget 8:87860-87877 (2017). Read more (PubMed: 29152126) »
  • Wang S  et al. Evodiamine synergizes with doxorubicin in the treatment of chemoresistant human breast cancer without inhibiting P-glycoprotein. PLoS One 9:e97512 (2014). Functional Studies . Read more (PubMed: 24830744) »

See all 2 Publications for this product

Customer reviews and Q&As

The correct assay method for the kit ab112142 is read from bottom (fluorescence intensity in live cells) using a microplate with opaque wall (black or white) but a transparent bottom. The fluorescence intensity will increase (inside of the live cells) ...

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We do not have in-house data for non-adherent cells but customers have reported using the assay with that kind of sample successfully. We do not have their data though. As far as we know, getting good results with cells in suspension is no more difficu...

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