The 1A1-K21-M22 monoclonal antibody specifically binds to CD267 which is also known as TACI (Transmembrane Activator and CAML Interactor). CD267 is a member of the of the Tumor Necrosis Factor Receptor (TNFR) Superfamily and is encoded by the TNFRSF13B gene. This 32 kDa type III transmembrane protein receptor binds to the ligands, BAFF (TNFSF13B/BLyS/CD257) and APRIL (TNFSF13/CD256). Ligand-bound CD267 transduces signals leading to the activation of transcription factors including NFAT, AP1, and NF-kappa-B. CD267 is expressed most notably on maturing subsets of B cells and myeloma cells. In CD267 deficient mice, B cell numbers are increased and mice develop autoimmune disorders suggesting that CD267 plays an important role in the regulation of B cell homeostasis.
The antibody was conjugated to BD Horizon™ BV421 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max at 421-nm, BD Horizon BV421 can be excited by the violet laser and detected in the standard Pacific Blue™ filter set (eg, 450/50-nm filter). BD Horizon BV421 conjugates are very bright, often exhibiting a 10 fold improvement in brightness compared to Pacific Blue conjugates.