The TÜ12 monoclonal antibody specifically recognizes CD99, also referred to as E2 antigen, a 32 kDa sialoglycoprotein expressed on all leucocyte lineages. The E2 antigen is the MIC2 gene product and is differentially expressed during T- and B-lymphoid and granulocytic development, with higher densities being expressed during early hematopoietic stages. Mature granulocytes express very little or no CD99. E2 has been shown to be involved in T-cell adhesion processes and is suggested to have a functional role in hematopoietic adhesion pathways.
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.