The MIH18 monoclonal antibody specifically binds to CD273 which is also known as the Programmed Death Ligand 2 (PD-L2) and B7-DC. CD273 is a type 1 transmembrane glycoprotein member of the B7 family and Ig superfamily. CD273 serves as a ligand for CD279, the Programmed Death 1 (PD-1) receptor. CD273 is expressed by dendritic cells, activated monocytes, medullary thymic epithelial cells, placental trophoblasts, and myocardial endothelium. CD273 can function as a coinhibitor of T cell functions by acting through CD279. Monoclonal antibodies that block the CD273 and CD279 interaction result in enhanced T cell proliferation and cytokine production. Thus, CD273 can play an important role in regulating T cell responses. Clone MIH18 is reportedly a blocking antibody.
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 or other oligo-dT-based capture systems. The 5' PCR handle allows for efficient sequencing library generation for Illumina sequencing platforms.