The 2D10.4 monoclonal antibody, also known as 2D10, specifically recognizes CD80 which is otherwise known as Activation B7-1 antigen (B7-1), B7.1, or B7. This ~60 kDa single-pass type I transmembrane glycoprotein is encoded by CD80 (CD80 molecule) that belongs to the immunoglobulin gene superfamily (IgSF). CD80 (B7-1) is comprised of an extracellular region with an IgV-like domain followed by an IgC-like domain, a transmembrane region and a cytoplasmic tail. It is variably expressed on activated B cells, activated CD4+ and CD8+ T cells, macrophages, and dendritic cells. CD80 (B7-1) serves as a ligand for the CD28 and CD152 (CTLA-4) coreceptors that are differentially expressed on T cells. CD80 (B7-1) engagement of CD28 costimulates T cells activated through their TCR-CD3 complex whereas its interaction with CD152 (CTLA-4) generates an inhibitory signal for T cell responses.
The antibody was conjugated to BD Horizon™ BV650 which is part of the BD Horizon Brilliant™ Violet family of dyes. This dye is a tandem fluorochrome of BD Horizon BV421 with an Ex Max of 405-nm and an acceptor dye with an Em Max at 650-nm. BD Horizon BV650 can be excited by the violet laser and detected in a filter used to detect APC-like dyes (eg, 660/20-nm filter). Due to the excitation and emission characteristics of the acceptor dye, there will be spillover into the APC and Alexa Fluor® 700 detectors. However, the spillover can be corrected through compensation as with any other dye combination.