The 458811 monoclonal antibody specifically recognizes Tetraspanin-8 (TSPAN8) that belongs to the Transmembrane 4 (Tetraspanin) superfamily (TM4SF). This molecule is also known as Transmembrane 4 superfamily member 3 (TM4SF3) or Tumor-associated antigen CO-029 (CO-029). TSPAN8 is a ~27-34 kDa protein that spans the membrane four times with transmembrane segments and has intracellular N- and C-termini. TSPAN8 has a small and a large extracellular loop that can mediate dimerization and association with other molecules including integrins, proteases, or cell signaling receptors. TSPAN8 is expressed on hematopoietic progenitor cells, non-keratinized squamous epithelium, endothelial cells, smooth and skeletal muscle cells as well as multiple tumor cell types. TSPAN8 is involved in angiogenesis, thrombosis, epithelial wound healing and may contribute to tumor cell metastasis.
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.