The D12 monoclonal antibody specifically binds to CD11b which is also known as Integrin alpha M (Integrin αM), Mac-1 subunit alpha (Mac-1a) or complement receptor 3 alpha chain (CR3a). CD11b is encoded by ITGAM (integrin subunit alpha M) and belongs to the integrin alpha subunit gene family. CD11b is expressed as a ~165-kDa type I transmembrane glycoprotein that associates with the ~95-kDa integrin β2 (CD18) to form the heterodimeric CD11b/CD18 (αM/β2) complex which also known as Mac-1 or CR3. CD11b is expressed on monocytes, dendritic cells, granulocytes, as well as on some T cells, B cells, and NK cells. CD11b functions in cell-cell and cell-substrate interactions and is a receptor for multiple ligands including inactivated C3b (iC3b), ICAM-1 (CD54), ICAM-2 (CD102), ICAM-3 (CD50) or fibrinogen. Mac-1 regulates leucocyte adhesion and migration, as well as phagocytosis of opsonized particles.
CAUTION Binding of this CD11b antibody depends on the presence of Ca++. EDTA or ACD, as anticoagulant might affect binding. Using heparin as an anticoagulant or removal of the anticoagulant is recommended.
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.