The IP26 monoclonal antibody specifically recognizes a monomorphic determinant on the αβ T-cell receptor (TCRαβ). The TCRαβ is a disulfide-linked 80 kDa heterodimer consisting of a 44 kDa α chain and a 37 kDa β chain. The TCRαβ is normally expressed on 50-70% of thymocytes and on a large fraction of mature T cells including greater than 95% of peripheral blood CD3+ T cells. The TCRαβ serves as a receptor for peptide antigens bound to MHC molecules. The IP26 antibody is mitogenic and useful for the flow cytometric analysis of TCRαβ+ T-cell subsets.
The antibody was conjugated to BD Horizon™ BUV563 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 which has an Ex Max of 348 nm and an acceptor dye. The tandem has an Em Max at 563 nm. BD Horizon BUV563 can be excited by the 355 nm ultraviolet laser. On instruments with a 561 nm Yellow-Green laser, the recommended bandpass filter is 585/15 nm with a 535 nm long pass to minimize laser light leakage. When BD Horizon BUV563 is used with an instrument that does not have a 561 nm laser, a 560/40 nm filter with a 535 nm long pass may be more optimal. Due to the excitation and emission characteristics of the acceptor dye, there may be spillover into the PE and PE-CF594 detectors. However, the spillover can be corrected through compensation as with any other dye combination.