The TU39 monoclonal antibody specifically recognizes human major histocompatibility (MHC) Class II HLA-DR, DP and most DQ antigens. These antigens are encoded by genes within the Human Leukocyte Antigen (HLA) Complex located on chromosome 6. MHC Class II antigens are transmembrane heterodimeric glycoproteins composed of α chain (36 kDa) and β chain (27 kDa) subunits. They are expressed primarily on antigen presenting cells which include dendritic cells, monocytes, macrophages, thymic epithelial cells, and B cells. They are also expressed on activated T cells. This molecule plays a major role in mediating cellular interactions during antigen presentation to CD4+ T lineage cells. The TU39 antibody is reportedly useful for immunophenotyping as well as functional studies including the inhibition of mixed lymphocyte reactions and antibody-mediated complement fixation on target cells.
The antibody was conjugated to BD Horizon BUV615 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome with an Ex Max near 350 nm and an Em Max near 615 nm. BD Horizon Brilliant BUV615 can be excited by the ultraviolet laser (355 nm) and detected with a 610/20 filter and a 595 nm LP. Due to the excitation of the acceptor dye by the blue/yellow-green laser line, there may be significant spillover into channels detecting PE-CF594 like emissions (eg, 610/20-nm filter).