The B3 monoclonal antibody specifically recognizes the human variable γ9 subunit (Vγ9) of γ/δ T-cell receptor (TCR). The γ/δ TCR is composed of two disulfide-linked glycoproteins. The gamma chain is approximately 45-60 kD and is detected on a small subset peripheral blood T cells and thymocytes. The majority of normal peripheral blood γ/δ T cells express a Vγ9+/Vδ2+ phenotype. The reason for this selection in the T-cell repertoire is not well understood.
The antibody was conjugated to BD Horizon Red 718, which has been developed exclusively for BD Biosciences as a better alternative to Alexa Fluor® 700. BD Horizon Red 718 can be excited by the red laser (628 – 640 nm) and, with an Em Max around 718 nm, it can be detected using a 730/45 nm filter. Due to similar excitation and emission properties, we do not recommend using R718 in combination with APC-R700 or Alexa Fluor® 700.