The J4-117 monoclonal antibody specifically recognizes CD72. CD72 is a 39-43 kDa type II integral membrane protein that belongs to the C-type lectin superfamily. CD72 is expressed on B cells from early precursor stages through mature B cells. CD72 is not expressed on plasma cells. CD72 is also expressed on follicular dendritic reticulum cells and some macrophages. CD72 has been reported to bind to CD5, a glycoprotein expressed on all mature T cells and a subpopulation of B cells, suggesting a role in regulating T- and B-cell activation and proliferation.
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.