The X40 hybridoma was derived from the fusion of mouse Sp2/0-Ag 14 myeloma cells with spleen cells from BALB/c mice immunized with keyhole limpet hemocyanin (KLH). The hybridoma secretes monoclonal antibody that binds specifically to KLH, an antigen not expressed on human cells or human cell lines.
The antibody was conjugated to BD Horizon™ BV421 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max near 407 nm and Em Max near 421 nm, BD Horizon™ BV421 can be excited by the violet laser (405 nm) and detected with a 450/50 nm filter. BD Horizon™ BV421 conjugates are very bright, often exhibiting a 10 fold improvement in brightness compared to Pacific Blue™ conjugates. Due to nearly identical excitation and emission properties but different spillover characteristics, BD Horizon™ BV421, Pacific Blue™, and BD Horizon™ V450 cannot be used simultaneously.