The 4B4-1 monoclonal antibody specifically binds to CD137 which is also known as 4-1BB, and ILA (induced by lymphocyte activation). CD137 is a type I transmembrane glycoprotein that belongs to the TNF/NGF receptor family. It is encoded by TNFRSF9 (tumor necrosis factor receptor superfamily, member 9). CD137 is expressed on activated T cells, B cells, monocytes, and follicular dendritic cells. CD137 plays roles in the costimulation, differentiation and survival of T cells and B cells.
This antibody is conjugated to BD Horizon™ BV605 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max of 602-nm, BD Horizon BV605 can be excited by a violet laser and detected with a standard 610/20-nm filter set. BD Horizon BV605 is a tandem fluorochrome of BD Horizon BV421 and an acceptor dye with an Em max at 605-nm. Due to the excitation of the acceptor dye by the green (532 nm) and yellow-green (561 nm) lasers, there will be significant spillover into the PE and BD Horizon PE-CF594 detectors off the green or yellow-green lasers. BD Horizon BV605 conjugates are very bright, often exhibiting brightness equivalent to PE conjugates and can be used as a third color off of the violet laser.