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 BV421 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max at 421-nm, BD Horizon BV421 can be excited by the violet laser and detected in the standard Pacific Blue™ filter set (eg, 450/50-nm filter). BD Horizon BV421 conjugates are very bright, often exhibiting a 10 fold improvement in brightness compared to Pacific Blue conjugates.