The 15D3 monoclonal antibody specifically recognizes P-glycoprotein which is also known as CD243, ATP-binding cassette subfamily B member 1 (ABCB1) or Multidrug resistance protein 1 (MDR1). P-glycoprotein is a ~170 kDa transmembrane glycoprotein protein that spans the membrane 12 times. P-glycoprotein acts as an ATP-dependent efflux pump for a large variety of drugs. It may be expressed at high levels by multidrug resistant (MDR) tumor cells. This efflux activity may lead to cellular resistance to the drugs used in chemotherapy. P-glycoprotein is present in many normal cell types including endothelial, epithelial, or secretory cells, and might protect them from naturally occurring xenobiotics.
The antibody was conjugated to BD Horizon Red 718, which has been developed exclusively for BD Biosciences as a better alternative to Alexa Fluor® 700. BD Horizon Red 718 can be excited by the red laser (628 – 640 nm) and, with an Em Max around 718 nm, it can be detected using a 730/45 nm filter. Due to similar excitation and emission properties, we do not recommend using R718 in combination with APC-R700 or Alexa Fluor® 700.