The HM48-1 monoclonal antibody specifically binds to CD48 (previously known as BCM1 in mice, Blast-1 in human, and OX-45 in the rat), a GPI-anchored member of the Ig superfamily. It is widely distributed on leukocytes, but not on non-hematopoietic cells, and its ligands include CD2 (LFA-2) and CD244 (2B4 antigen). The HM48-1 mAb blocks binding of soluble CD2 to CD48-bearing cells, blocks the interaction of CD2 and CD244, inhibits spleen cell proliferative responses to mitogens, augments the proliferative response of spleen cells when cross-linked with anti-CD3e mAbs, and inhibits priming of CTL in vitro. In vivo administration of HM48-1 antibody can prolong survival of cardiac allografts, an effect which is greatly enhanced by the addition of anti-CD2 mAb 12-15. This hamster mAb to a mouse leukocyte antigen does not cross-react with rat leukocytes.
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.