The RR4-7 antibody specifically reacts with the Vβ 6 T-Cell Receptor (TCR) of mice having the a (e.g., C57BR, C57L, SJL) and b (e.g., A, BALB/c, CBA/Ca, C3H/He, C57BL, DBA/1) haplotypes of the Tcrb gene complex. The Tcrb-V6 gene locus is deleted in mice having the c (e.g., RIII) haplotype. Vβ 6 TCR-bearing T lymphocytes are clonally eliminated in mice expressing superantigen encoded by Mtv-7 (Mls-1[a], Mls[a]) endogenous provirus (e.g., AKR, CBA/J, C58, DBA/2, NZB), or Mtv-43 endogenous provirus (e.g., MA/MyJ). Exogenous MMTV-SW, as well as endogenous Mtv-44-encoded superantigen (e.g., NZW), also causes incomplete elimination of Vβ 6 TCR-expressing T cells. Plate-bound RR4-7 antibody activates Vβ 6 TCR-bearing T cells, soluble RR4-7 mAb blocks in vitro proliferation and cytolytic activities of Vβ 6 TCR-bearing T-cell clones, and injection of the antibody results in in vivo depletion of Vβ 6 TCR-bearing T cells.
The antibody was conjugated to BD Horizon™ BUV496 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 with an Ex Max of 348-nm and an acceptor dye with an Em Max at 496-nm. BD Horizon BUV496 can be excited by the ultraviolet laser (355 nm) and detected with a 515/30 nm filter with a 450LP. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into the channel detecting BD Horizon V500 or BV510 (eg, 525/40-nm filter). However, the spillover can be corrected through compensation as with any other dye combination.