The BM16 monoclonal antibody specifically binds to CD294. CD294 is encoded by PTGDR2 (Prostaglandin D2 receptor 2) and is also known as CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells), GPR44 (G protein-coupled receptor 44), DL1R, and DP2. CD294 is a member of the G protein-coupled leukocyte chemoattractant receptor family. CD294 is expressed on Th2 cells and type-2 innate lymphoid cells (ILC2), but not Th1 type cells. CD294 is detectable on CD4+ T cells in fresh PBMC but not on B cells and NK cells. CD294 is also expressed on peripheral blood basophils and eosinophils, suggesting its involvement allergic reactions. Phenotypic analysis of CD4+ T cells expressing CRTH2 demonstrated that they were also CD45RA-negative and CD45RO+ and CD25+. These cells produce Th2- but little or no Th1-type cytokines upon stimulation with PMA and Ionomycin.
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.