The 4A6 monoclonal antibody specifically recognizes mouse PDC-TREM, also known as TREM-4, which is a member of the Triggering Receptor Expressed on Myeloid cells (TREM) family of protein-binding receptors that regulate innate immune responses. Stimulation of plasmacytoid dendritic cells (pDCs) through toll-like receptors (TLRs) induces type I interferon production and PDC-TREM expression. Cell-surface expression and immune regulatory signaling by PDC-TREM require its association with Plexin-A1 and DNAX-activation Protein 12 (DAP12) and further augments type I interferon production by pDCs.
The antibody was conjugated to BD Horizon™ BV650 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 650-nm. BD Horizon BV650 can be excited by the violet laser and detected in a filter used to detect APC-like dyes (eg, 660/20-nm filter). Due to the excitation and emission characteristics of the acceptor dye, there will be spillover into the APC and Alexa Fluor® 700 detectors. However, the spillover can be corrected through compensation as with any other dye combination.