The J168-540 monoclonal antibody specifically binds to human CD272, also known as BTLA (B and T lymphocyte attenuator), an inhibitory receptor expressed in bone marrow and thymus on developing B and T cells. In the periphery, BTLA is expressed by B cells, T cells, bone marrow-derived dendritic cells, and macrophages. After T cell activation, BTLA appears to be expressed at higher levels on Th1 cell populations than in Th2 cell populations. Upon binding the herpesvirus entry mediator (HVEM/LIGHT-R/CD270), CD272 undergoes tyrosine phosphorylation and inhibits T cell proliferation in a BTLA-dependent manner. CD272 has structural similarities to two other lymphocyte inhibitory receptors, CTLA-4 and PD-1 and is a member of the CD28-like family of coreceptors. Based on these observations, CD272 is considered to be a negative regulator of lymphocyte activation and/or function.
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.