The 3F1 monoclonal antibody specifically binds to CD155, which is also known as Poliovirus receptor (Pvr) or Tumor-associated antigen 1 (Taa1). CD155 is a type I transmembrane glycoprotein that belongs to the Ig supergene family. CD155 is an adhesion receptor that binds to different ligands including nectin-3, CD96, CD226, TIGIT, and the extracellular matrix protein vitronectin. It is highly expressed on double positive thymocytes and variably expressed on mature thymocytes and T cells, including regulatory T cells and NKT cells. CD155 is also differentially expressed on subsets of B cells, plasma cells, dendritic cells, and monocytes. CD155 expression is upregulated by activated T cells, B cells, and dendritic cells. CD155 is involved in forming adherens junctions between adjacent epithelial or endothelial cells. CD155 plays roles in regulating cell growth, adhesion, motility, migration, and cell-mediated cytotoxicity. CD155-deficient mice exhibit impaired secondary humoral immune responses to orally administered antigens.
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.