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™ BUV496 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 with an Ex Max of 348-nm and an acceptor dye with an Em Max at 496-nm. BD Horizon BUV496 can be excited by the ultraviolet laser (355 nm) and detected with a 515/30 nm filter with a 450LP. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into the channel detecting BD Horizon V500 or BV510 (eg, 525/40-nm filter). However, the spillover can be corrected through compensation as with any other dye combination.