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™ BUV563 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 which has an Ex Max of 348 nm and an acceptor dye. The tandem has an Em Max at 563 nm. BD Horizon BUV563 can be excited by the 355 nm ultraviolet laser. On instruments with a 561 nm Yellow-Green laser, the recommended bandpass filter is 585/15 nm with a 535 nm long pass to minimize laser light leakage. When BD Horizon BUV563 is used with an instrument that does not have a 561 nm laser, a 560/40 nm filter with a 535 nm long pass may be more optimal. Due to the excitation and emission characteristics of the acceptor dye, there may be spillover into the PE and PE-CF594 detectors. However, the spillover can be corrected through compensation as with any other dye combination.