The 927 monoclonal antibody specifically recognizes CD317 which is also known as Bone marrow stromal antigen 2 (BST2) or Plasmacytoid Dendritic Cell Ag-1 (PDCA-1). CD317 (BST2) is a type II transmembrane glycoprotein that is encoded by Bst2. It is highly expressed on naïve plasmacytoid dendritic cells (pDC) which comprise very small populations within lymphoid and nonlymphoid tissues. pDC are characteristically early responders to viruses through Toll-like receptors (TLR), TLR7 and TLR9. Activated pDC can produce large amounts of proinflammatory cytokines including type I interferons, Interferon-alpha (IFN-α) and Interferon-beta (IFN-β), and are also known as Type I IFN producing cells (IPC). CD317 (BST2) expression can be upregulated on a variety of other cell types following stimulation with type I IFNs and IFN gamma including T cells, B cells, plasma cells, NK cells, CD8+ and CD8- dendritic cells, and cell lines. CD317 (BST2) may play a role in sorting proteins, eg, cytokines, from the Golgi apparatus and the plasma membrane.
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).