The CerCLIP monoclonal antibody specifically recognizes the class II associated invariant chain peptides (CLIP). CLIP is the remaining segment of class II invariant chain (Ii) after proteolytic degradation which stays associated with HLA-DR and represents a final intermediate in the removal of invariant chain from class II molecules during antigen processing. The removal of CLIP and subsequent loading of the antigenic peptide is facilitated by the non-classical class II molecule HLA-DM. CLIP can be detected, in association with HLA-DR, on the surface of T2DR3, a mutant cell line lacking HLA-DM.
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.