Clone MY31 specifically recognizes the human form of the 220/135 kDa heavily glycosylated antigen, CD56, found on a subpopulation of peripheral blood large granular lymphocytes which demonstrate natural killer cell activity, but not on myeloid cells, erythrocytes or B cells. This clone also cross-reacts with a subset of peripheral blood lymphocytes of baboon, and both rhesus and cynomolgus macaque monkeys. The distribution on lymphocytes is similar to that observed with peripheral blood lymphocytes from normal human donors, with a subset of CD16+ cells co-expressing CD56. In contrast to what is observed with human peripheral blood cells, however, clone MY31 also reacts with a major subset of non-human primate CD14+ monocytes. Studies in rhesus macaque monkeys suggest that CD56 reacts with monocytes and not natural killer cells.
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.