The HP-3D9 monoclonal antibody specifically binds to CD94 which is also known as KP43. CD94 is expressed on the cell surface as a ~70 kDa, disulfide-linked, type II transmembrane glycoprotein dimer. It is encoded by KLRD1 (Killer cell lectin like receptor D1) which belongs to the C-type lectin superfamily. CD94 is expressed on natural killer (NK) cells, especially activated NK cells. It is also expressed on γ/δ TCR+ T lymphocytes, NK-T cells, and on some CD8+CD56+ α/β TCR+ cells. CD94 associates with various NKG2 receptors to form receptors for HLA class I molecules and plays a role in regulating cellular adhesion and activation. The HP-3D9 antibody can reportedly inhibit the cytolytic activity of activated NK cells.
The antibody was conjugated to BD Horizon™ BUV496 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 496-nm. BD Horizon BUV496 can be excited by the ultraviolet laser (355 nm) and detected with a 515/30 nm filter with a 450LP. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into the channel detecting BD Horizon V500 or BV510 (eg, 525/40-nm filter). However, the spillover can be corrected through compensation as with any other dye combination.