Monoclonal antibody 6B11 reacts with a unique determinant in the CDR3 region of the invariant (Vα24-JαQ) TCR chain. Thus 6B11 identifies a subset of all Vα24 positive T cells. The binding of the PE-conjugate of 6B11 can be partially blocked by other antibodies specific for Vα24 (BD Biosciences Pharmingen, data not shown). This invariant chain is expressed on invariant NK T cells, which are a small subset of T lymphocytes that also express other NK cell molecules such as CD161. Invariant NK T cells have been reported to play an immunoregulatory role. The Vα24-JαQ interacts with the CD1d protein. Invariant NK T cells can be specifically activated by CD1d-presented antigen resulting in rapid production of IL-4 and IFN (also known as IFN-γ). Studies of NK T cells describe their role in anti-tumor immunity and autoimmunity.
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.