The 7H11 monoclonal antibody specifically recognizes mouse CD370 which is also known as DNGR-1 (Dendritic cell natural killer lectin group receptor 1). CD370 is an ~27 kDa single-pass type II transmembrane glycoprotein that is encoded by Clec9A (C-type lectin domain family member 9A) which belongs to the C-type lectin superfamily. CD370 (Clec9a) is selectively expressed as a disulfide-linked homodimer on plasmacytoid dendritic cells and CD8+ myeloid dendritic cells. This receptor is comprised of an extracellular region that contains a C-type lectin domain with a single carbohydrate recognition domain (CRD), followed by a transmembrane segment and a cytoplasmic tail with an immunoreceptor tyrosine-based activation motif (ITAM). CD370 (Clec9a) acts as a damage-associated molecular pattern receptor, ie, an endocytic receptor for damage-associated molecular patterns (DAMPs) that are expressed by necrotic cells, eg, cells dying due to infection or transformation. This receptor binds by its extracellular domain to exposed F-actin-myosin complexes of dead cells. Intracellular signaling mediated through ligand-bound CD370 (Clec9a) leads to phosphorylation of Syk tyrosine kinase. Further downstream signaling can foster MHC Class I-mediated cross-presentation of dead-cell associated antigens by dendritic cells to CD8+ T cells.
The antibody was conjugated to BD Horizon BV750 which is part of the BD Horizon Brilliant™ Violet family of dyes. This dye is a tandem fluorochrome of BD Horizon BV421 with an Ex Max of 405-nm and an acceptor dye with an Em Max at 750-nm. BD Horizon Brilliant BV750 can be excited by the violet laser (405 nm) and detected with a 750/30 nm filter with a 740 nm long pass. Due to spectral differences between labeled cells and beads, using BD™ CompBeads can result in incorrect spillover values when used with BD Horizon BV750 reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended.