The B1.1 monoclonal antibody binds to several glycosylphosphatidylinositol-anchored glycoproteins present on granulocytes and epithelial cells. As reported in the Sixth International Workshop and Conference on Human Leucocyte Differentiation Antigens, the B1.1 antibody recognized CD66a (CEACAM1), CD66c (CEACAM6), CD66d (CEACAM3) and CD66e (CEACAM5). CD66 antigens belong to the carcinoembryonic antigen (CEA) family of molecules that are closely related to the immunoglobulin superfamily of glycoproteins. Studies on CD66 molecules suggest a potential adhesion function in vivo. These molecules exhibit both homophilic and heterophilic adhesion. CEA family members may be involved in transmembrane signaling and activation of neutrophils.
The antibody was conjugated to BD Horizon Red 718, which has been developed exclusively for BD Biosciences as a better alternative to Alexa Fluor® 700. BD Horizon Red 718 can be excited by the red laser (628 – 640 nm) and, with an Em Max around 718 nm, it can be detected using a 730/45 nm filter. Due to similar excitation and emission properties, we do not recommend using R718 in combination with APC-R700 or Alexa Fluor® 700.