The MIH44 monoclonal antibody specifically binds to Glucocorticoid-induced TNF-related Ligand (GITR Ligand). The GITR Ligand protein is encoded by the Tnfsf18 (Tumor necrosis factor ligand superfamily member 18) gene. The GITR Ligand is a type II transmembrane protein that is expressed on endothelial cells and antigen presenting cells, including B cells, macrophage and dendritic cells. The GITR Ligand reportedly costimulates T cell activation and reverses CD4+CD25+ Treg cell-mediated suppression by interaction with its cognate receptor, GITR that is expressed by these cells.
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.