The L178 monoclonal antibody specifically binds to CD44 which is also known as Homing-associated cell adhesion molecule (H-CAM) or Phagocytic glycoprotein 1 (Pgp-1). CD44 is a single-pass type I transmembrane glycoprotein that exists in a variety of isoforms also known as variant CD44 (CD44v) or CD44R forms. CD44 is synthesized as a 37 kDa polypeptide that is converted to an 80-95 kDa form by glycosylation via N- and O-linkages, or to a 180-200 kDa form by the addition of chondroitin sulfate. It is expressed on leucocytes, erythrocytes, epithelial cells and weakly on platelets. Depending on the cell type, CD44 may participate in a variety of functions including cell adhesion, motility and cell activation.
The antibody was conjugated to BD Horizon™ BUV496 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 with an Ex Max of 348-nm and an acceptor dye with an Em Max at 496-nm. BD Horizon BUV496 can be excited by the ultraviolet laser (355 nm) and detected with a 515/30 nm filter with a 450LP. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into the channel detecting BD Horizon V500 or BV510 (eg, 525/40-nm filter). However, the spillover can be corrected through compensation as with any other dye combination.