The FR70 monoclonal antibody specifically binds to mouse CD70, a 30-33-kDa type-II transmembrane glycoprotein belonging to the TNF/NGF superfamily. CD70 is the ligand for CD27 and is expressed primarily on activated B cells. CD70 expression can be induced by activation of splenocytes with lipopolysaccharide and stimulatory antibodies specific for IgM, CD40 or both. mRNA coding for CD70 is transiently expressed after Concanavalin A stimulation of splenocytes or thymocytes. CD70 has been observed to be expressed on dendritic cells of Leishmania major-infected mice. The CD27-CD70 interaction delivers costimulatory signals to T cells and NK cells. It has been reported that FR70 antibody blocks binding of mCD27-Ig fusion protein to mouse Cd70-transfected cells and inhibits some in vitro T-cell- and NK-cell-dependent responses.
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.