The 15E2 monoclonal antibody specifically binds to CD369 which is also known as CLEC7A (C-type lectin domain family 7 member A), Dectin-1 (Dendritic cell-associated C-type lectin 1), or BGR (Beta-glucan receptor). CD369 is a type II transmembrane C-type lectin that contains a C-terminal stalk with a carbohydrate recognition domain (CRD) in the extracellular domain, a transmembrane segment, and an ITAM containing cytoplasmic tail. This protein is highly expressed on dendritic cells. It is also expressed on B cells, monocytes, eosinophils, mast cells, macrophages, endothelial cells, and is lowly expressed on some subsets of T cells. CD369 binds to beta-glucan polymers and functions as a pattern recognition receptor in innate immune response to fungal and bacterial pathogens. The 15E2 antibody can reportedly stimulate dendritic cells to costimulate immune responses.
The antibody was conjugated to BD Horizon™ BUV737 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 with an Ex Max of 348-nm and an acceptor dye with an Em Max at 737-nm. BD Horizon Brilliant BUV737 can be excited by the ultraviolet laser (355 nm) and detected with a 740/35 filter. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into channels detecting Alexa Fluor® 700-like dyes (eg, 712/20-nm filter).
Due to spectral differences between labeled cells and beads, using BD™ CompBeads can result in incorrect spillover values when used with BD Horizon BUV737 reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended. Different BUV737 reagents (eg, CD4 vs. CD45) can have slightly different fluorescence spillover therefore, it may also be necessary to use clone specific compensation controls when using these reagents.