The HBF-719 antibody reacts with the B6 alloantigen of Ly-49F, an inhibitory receptor which is expressed on subsets of natural killer (NK) cells, NK-1.1+ (or DX5+) T lymphocytes (NK-T cells), and on a population of memory CD8+ T lymphocytes in C57BL/6 mice, 1 but not AKR/J, BALB/c, C3H/HeN, DBA/1, or SJL mice.3 The Ly-49 family of NK-cell receptors are disulfide linked type-II transmembrane protein homodimers with extracellular carbohydrate recognition domains (CRD). The Ly-49 family members are expressed independently, such that an individual NKor T-cell may display more than one class of Ly-49 receptor homodimers. Ly-49F has an ITIM (Immunoreceptor Tyrosine-based Inhibitory Motif) in its cytoplasmic tail. Therefore, it is probably an inhibitory receptor. It weakly binds to cells expressing the H-2d MHC class I alloantigens.
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.