The N418 monoclonal antibody specifically binds to CD11c, the Integrin alpha X (Integrin αX, Itgax) chain of the heterodimeric gp150, 95 (CD11c/CD18, αXβ2) integrin that forms the complement receptor 4 (CR4). CD11c is a150 kDa type I transmembrane glycoprotein that is expressed on dendritic cells, CD4-CD8+ intestinal intraepithelial lymphocytes (IEL), and some NK cells and T cells. CD11c expression is upregulated on IEL and T cells following activation. Cells of the monocyte/macrophage lineage have been reported to express low levels of CD11c. The CD11c/CD18 integrin can bind to several ligands including iC3b, fibrinogen, and CD54. This integrin reportedly plays important roles in phagocytosis and in mediating cellular interactions during inflammation.
The antibody was conjugated to BD Horizon BB515 which is part of the BD Horizon Brilliant™ Blue family of dyes. With an Ex Max near 490 nm and an Em Max near 515 nm, BD Horizon BB515 can be excited by the blue laser (488 nm) laser and detected with a 530/30 nm filter. This dye has been exclusively developed by BD Biosciences and is up to seven times brighter than FITC with less spillover into the PE channel. Due to similar excitation and emission properties, BB515, FITC, and Alexa Fluor® 488 cannot be used simultaneously. It is not recommended to use BB515 in cocktails that include Streptavidin conjugates as it may cause high background.