The A1 monoclonal antibody specifically recognizes human CD39 which is also known as Ecto-ATP diphosphohydrolase 1 (Ecto-ATPase 1 or Ecto-ATPDase 1), Ecto-apyrase or NTPDase 1. CD39 is a ~78 kDa integral membrane glycoprotein that is encoded by ENTPD1 (Ectonucleoside triphosphate diphosphohydrolase 1). CD39 contains two transmembrane domains, one having a N- and the other a C-terminal cytoplasmic tail, and a large extracellular domain that has the enzymatic site. CD39 is also known as Lymphoid cell activation antigen because its expression is induced upon activation of T and B cells. CD39 is variably expressed on some regulatory T cells, NK cells, granulocytes, monocytes, dendritic cells, Langerhans cells, endothelial cells, platelets, and neurons. CD39 is a member of the ectonucleoside triphosphate dihydrolases (E-NTPDases) family that is involved in the regulation of extracellular nucleotide catabolism by controlling the extracellular nucleoside triphosphate pool (NTP). It functions as an ectoenzyme that can hydrolyze both nucleoside triphosphates and diphosphates such as ATP and ADP and thereby suppress inflammation and regulate platelet activation as well as purinergic neurotransmission. The ectoenzymes CD39 and CD73 can act in tandem to enable regulatory T cells (Treg) to generate immunosuppressive adenosine and thereby regulate immune responses.
This antibody is conjugated to BD Horizon™ BV605 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max of 602-nm, BD Horizon™ BV605 can be excited by a violet laser and detected with a standard 610/20-nm filter set. BD Horizon™ BV605 is a tandem fluorochrome of BD Horizon™ BV421 and an acceptor dye with an Em max at 605-nm. Due to the excitation of the acceptor dye by the green (532 nm) and yellow-green (561 nm) lasers, there will be significant spillover into the PE and BD Horizon™ PE-CF594 detectors off the green or yellow-green lasers. BD Horizon™ BV605 conjugates are very bright, often exhibiting brightness equivalent to PE conjugates and can be used as a third color off of the violet laser.