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 BUV615 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome with an Ex Max near 350 nm and an Em Max near 615 nm. BD Horizon Brilliant BUV615 can be excited by the ultraviolet laser (355 nm) and detected with a 610/20 filter and a 595 nm LP. Due to the excitation of the acceptor dye by the blue/yellow-green laser line, there may be significant spillover into channels detecting PE-CF594 like emissions (eg, 610/20-nm filter).