The 7-517 monoclonal antibody specifically binds to CD276, also known as B7-H3 (B7 homolog 3). CD276 is a type I transmembrane glycoprotein and member of the B7 family of immunoregulatory proteins. Although the CD276 gene transcript is expressed in nearly all normal tissues, the protein is preferentially expressed in tumors, tumor cell lines, sinonasal epithelial cells, and extravillous trophoblast and Hofbauer cells of the placenta. CD276 protein expression can be induced by activation of T and B lymphocytes, natural killer (NK) cells and antigen-presenting cells. The roles of CD276 in the regulation of immune responses, especially to cancer, are under investigation.
The antibody was conjugated to BD Horizon™ BUV661 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 661-nm. BD Horizon Brilliant BUV661 can be excited by the ultraviolet laser (355 nm) and detected with a 670/25 filter and a 630 nm LP. Due to cross laser excitation of this dye, there may be significant spillover into channels detecting APC-like emissions (eg, 670/25-nm filter).
Due to spectral differences between labeled cells and beads, using BD™ CompBeads can result in incorrect spillover values when used with BD Horizon BUV661 reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended. Different BUV661 reagents (eg, CD4 vs. CD45) can have slightly different fluorescence spillover therefore, it may also be necessary to use clone-specific compensation controls when using these reagents.