The 1AH2 monoclonal antibody specifically binds to CD137. CD137 is a member of the TNFR/NGFR superfamily that is likewise known as Tnfrsf9, 4-1BB, Ly-63, or ILA. Monomers or multimeric forms of CD137 are expressed, upon activation, on the surface of splenic T lymphocytes, thymocytes, intestinal intraepithelial T lymphocytes (IEL), and some T cell lines and clones. While stimulating T cells by IL-2, IL-4, or anti-CD28 alone does not result in the expression of CD137; addition of IL-2, IL-4, anti-CD28, or syngeneic accessory cells to splenic T cells stimulated via TCR/CD3 can result in a high level CD137 expression. CD137 is also reportedly expressed on IL-2 activated NK cells, but not on freshly isolated NK cells. CD137 physically associates with p56 [lck] through a Cys-Arg-Cys-Pro binding site in its cytoplasmic domain; the same motif in the cytoplasmic tail of the CD4 and CD8a molecules is responsible for association with p56 [lck]. A signaling function for the CD137 molecule in mouse T cells is indicated by reports in which cross-linking of CD137 with 1AH2 mAb resulted in enhanced proliferation of CD3e-activated splenic T cells and IEL and in enhanced cytolytic activity of IEL in response to immobilized anti-CD3e. In addition to extracellular matrix proteins which bind to CD137, the CD137L (4-1BBL) serves as a ligand for CD137. This molecule has also been detected on LPS-activated macrophages, and anti-IgM antibody-activated splenic B cells. Interaction between T and B cells through CD137/CD137L is reported to play a role in antigen presentation, further supporting a costimulatory role for CD137 in the immune response of T lymphocytes.
The antibody was conjugated to an oligonucleotide that contains an antibody clone-specific barcode (ABC) flanked by a poly-A tail on the 3' end and a PCR handle (PCR primer binding site) on the 5' end. The ABC for this antibody was designed to be used with other BD AbSeq oligonucleotides conjugated to other antibodies. All AbSeq ABC sequences were selected in silico to be unique from human and mouse genomes, have low predicted secondary structure, and have high Hamming distance within the BD AbSeq portfolio, to allow for sequencing error correction and unique mapping. The poly-A tail of the oligonucleotide allows the ABC to be captured by the BD Rhapsody™ system. The 5' PCR handle allows for efficient sequencing library generation for Illumina sequencing platforms.
NOTE: The BD Rhapsody Single-Cell Analysis System must be used with the BD Rhapsody Express Instrument.