The IA10 monoclonal antibody specifically binds to CD55, which is also known as complement decay-accelerating factor (DAF). CD55 is a glycophosphatidylinositol (GPI)-anchored, single chain membrane glycoprotein of approximately 70 kDa that belongs to the regulators of complement activation (RCA) gene family which includes CD21, CD35, and CD46. CD55 is widely expressed on hematopoietic cells including platelets and erythrocytes, as well as on many non-hematopoietic cells, such as, endothelial cells and epithelial cells. CD55 is involved in protecting cells from damage by autologous activated complement complexes. CD55 prevents the amplification steps of the complement cascade by interfering with the assembly of the C3-convertases, C4b2a and C3bBb, and the C5-convertases, C4b2a3b and C3bBb3b.
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.