The OX-34 antibody reacts with CD2 (LFA-2), a member of the immunoglobulin superfamily. In the rat, CD2 is expressed on thymocytes, T lymphocytes in spleen and lymph node, dendritic epidermal T cells, splenic macrophages, and NK cells, but not on B cells, most intestinal intraepithelial lymphocytes, or peritoneal and liver macrophages. CD2 can associate with the T-cell receptor complex, and it may function in both intercellular adhesion and signal transduction. In the rat, CD48 and CD59 have been identified as ligands for CD2. OX-34 mAb binds to the extracellular portion of CD2, and it blocks the binding of CD2 to CD48. While OX-34 antibody does not activate T cells, it partially blocks activation by immobilized mAbs to CD3 (clone G4.18) and αβ T-cell receptor (clone R73), and it partially inhibits allogeneic mixed lymphocyte reactions. Moreover, in vivo administration of OX-34 antibody depletes peripheral T cells and prevents allograft rejection.
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).