The HIP1 monoclonal antibody specifically binds to CD42b. CD42b is also known as the Platelet glycoprotein Ib alpha chain that is encoded by the GP1BA gene. CD42b is disulfide bonded to CD42c to form a 170 kDa heterodimer, GPIb. GPIb forms a noncovalent complex with CD42a and CD42d (CD42 complex) that is expressed on platelets and megakaryocytes. The CD42 complex serves as the von Willebrand Factor (vWF) surface receptor involved in the adhesion of platelets to the subendothelium of damaged vascular walls. HIP1 inhibits the ristocetin-dependent binding of vWF to platelets and partially inhibits collagen-induced aggregation.
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.