The W6D3 monoclonal antibody specifically binds to 3-fucosyl-N-acetyllactosamine (3-FAL), a 220 kDa carbohydrate structure, also called X-hapten. 3-FAL is expressed on >95% of granulocytes, including neutrophils and eosinophils, and on monocytes to a varying degree, but not on lymphocytes or basophils. CD15 plays a role in mediating phagocytosis, bactericidal activity and chemotaxis. Most CD15 antibodies are IgM isotype; clone W6D3 is a mouse IgG1 isotype. In comparison studies with clone HI98, a known CD15 antibody, clone W6D3 shows brighter fluorescence staining and its binding can be blocked by clone HI98.
The antibody was conjugated to BD Horizon BUV615 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome with an Ex Max near 350 nm and an Em Max near 615 nm. BD Horizon Brilliant BUV615 can be excited by the ultraviolet laser (355 nm) and detected with a 610/20 filter and a 595 nm LP. Due to the excitation of the acceptor dye by the blue/yellow-green laser line, there may be significant spillover into channels detecting PE-CF594 like emissions (eg, 610/20-nm filter).