The B81-3 monoclonal antibody was raised against keyhole limpet hemocyanin (KLH), an antigen not expressed by mammalian cells or cell lines. Intended for use as a hamster immunoglobulin isotype control, the B81-3 antibody can be used as a negative control to help differentiate non-specific background signal when compared against a signal from a specific hamster antibody. The purified B81-3 antibody may also serve as a useful standard for some ELISA applications. KLH is a oxygen carrying metalloprotein from a species of keyhole limpet that lives off the coast of California and is often used as a carrier protein to help elicit immune responses to haptens. Since KLH is phylogenetically distant from many mammalian proteins, it often has very minimal to no cross-reactivity for many immunological assays.
The antibody was conjugated to BD Horizon BV711 which is part of the BD Horizon Brilliant™ Violet family of dyes. This dye is a tandem fluorochrome of BD Horizon BV421 with an Ex Max of 405-nm and an acceptor dye with an Em Max at 711-nm. BD Horizon BV711 can be excited by the violet laser and detected in a filter used to detect Cy™5.5 / Alexa Fluor® 700-like dyes (eg, 712/20-nm filter). Due to the excitation and emission characteristics of the acceptor dye, there may be moderate spillover into the Alexa Fluor® 700 and PerCP-Cy5.5 detectors. However, the spillover can be corrected through compensation as with any other dye combination.