The 174031 monoclonal antibody specifically recognizes CD354 which is also known as Triggering receptor expressed on myeloid cells 1 (TREM-1) or Triggering receptor expressed on monocytes 1. CD354 (TREM-1) is a ~30 kDa single-pass type I transmembrane glycoprotein that is encoded by Trem1 which belongs to the V-set domain containing family within the Ig superfamily. CD354 (TREM-1) can associate with DAP12, an adaptor protein that contains an immunoreceptor tyrosine-based activation motif (ITAM), to deliver an activating signal intracellularly. It is expressed on neutrophils and some monocytes and macrophages with upregulated expression triggered in response to bacterial lipopolysaccharide (LPS) exposure. CD354 (TREM-1) appears to play important roles in inflammation and septic shock by inducing the production of pro-inflammatory cytokines and chemokines including TNF and MCP-1/CCL2. A soluble form of TREM-1 may be released by cells and serve as an inhibitor of cell surface TREM-1 function.
The antibody was conjugated to BD Horizon™ BUV661 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 661-nm. BD Horizon Brilliant BUV661 can be excited by the ultraviolet laser (355 nm) and detected with a 670/25 filter and a 630 nm LP. Due to cross laser excitation of this dye, there may be significant spillover into channels detecting APC-like emissions (eg, 670/25-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 BUV661 reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended. Different BUV661 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.