The 16-10A1 monoclonal antibody specifically recognizes CD80 (B7-1). This member of the Ig superfamily, like CD86 (B7-2), can bind to either CD28 or CD152 (CTLA-4) and provide either costimulatory or coinhibitory signals to T cells, respectively. CD80 is constitutively expressed on dendritic cells, monocytes, and peritoneal macrophages as well as by activated B cells and T cells. The 16-10A1 antibody blocks binding of CTLA-4 Ig to CD80 as well as T-cell activation by Con A-elicited peritoneal exudate cells or CD80-transfected cell lines. However, the 16-10A1 antibody alone is not able to block T-cell activation by antigen-presenting cells. The 16-10A1 antibody may reportedly block the binding of another CD80-specific antibody, clone 1G10. In addition, the 16-10A1 antibody may crossreact with an activation antigen expressed on IFN-γ-activated alveolar macrophages of the dog.
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.