The C65-485 monoclonal antibody specifically recognizes the type II membrane protein known as 4-1BB Ligand (4-1BB-L) or CD137 Ligand (CD137L). This molecule belongs to the TNF superfamily and is encoded by TNFSF9 (Tumor necrosis factor superfamily member 9). CD137 Ligand has been reported to have costimulatory function on activated T cells. Reports suggest that stimulation of activated T cells via CD137 Ligand does not require the presence of other costimulatory molecules, including CD28. Some studies have reported human CD137 Ligand to be expressed preferentially on primary B cells and B-cell lines. The C65-485 antibody is able to react with recombinant human 4-1BB Ligand (rh4-1BB-L/CD137L) bound to CD137 (4-1BB receptor) expressed on phytohemagglutinin (PHA)-stimulated PBMC.
The antibody was conjugated to BD Horizon Red 718, which has been developed exclusively for BD Biosciences as a better alternative to Alexa Fluor® 700. BD Horizon Red 718 can be excited by the red laser (628 – 640 nm) and, with an Em Max around 718 nm, it can be detected using a 730/45 nm filter. Due to similar excitation and emission properties, we do not recommend using R718 in combination with APC-R700 or Alexa Fluor® 700.