The TU169 monoclonal antibody specifically binds to the human Major Histocompatibility Complex (MHC) Class II HLA-DQ1 and DQ2 antigens and weakly to HLA-DQ3. HLA-DQ antigens exits as heterodimers comprised of polymorphic transmembrane HLA-DQ alpha and beta glycoproteins. HLA-DQ is expressed primarily on B cells, monocytes, macrophages, dendritic cells and activated T lymphocytes. HLA-DQ is involved in presenting peptidic antigens to CD4+ T lymphocytes. This antibody does not cross-react with HLA-DR2 and HLA-DR7. This antibody fixes complement.
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.