The MIH5 monoclonal antibody specifically binds to CD274, also known as B7-H1 or PDL1, a 43-kDa glycoprotein encoded by the Pdcd1lg1 gene of the B7 family of the Ig superfamily. Pdcd1lg1 mRNA is expressed in more tissues than other members of the B7 family; transcripts are found in lymphoid tissues and many, but not all, non-lymphoid tissues. The protein has been detected at low levels on resting peripheral T and B lymphocytes, macrophages, and dendritic cells. B7-H1 mRNA and protein expression are upregulated upon activation of T and B cells, macrophages, dendritic cells, and epidermal keratinocytes by a variety of stimulatory factors. B7-H1's receptor, PD-1, contains an ITIM (Immunoreceptor Tyrosine-based Inhibitory Motif) on its intracytoplasmic region and is expressed on activated B and T lymphocytes, suggesting that B7-H1-PD-1 interaction may be involved in the negative regulation of immune responses. The second PD-1 ligand, B7-DC (PD-L2), is also a member of the B7 family of the Ig superfamily. Furthermore, B7-H1 may participate in positive immunoregulation, or costimulation of T cells, through an additional receptor, which is not PD-1 and distinct from the alternate receptor for B7-DC. The MIH5 antibody blocks the binding of PD-1-Ig to B7-H1 transfectants.
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.