The TX99 monoclonal antibody specifically binds to T cell immunoreceptor with Ig and ITIM domains (TIGIT), which is also known as V-set and transmembrane domain-containing protein 3 (Vstm3). TIGIT is a 26-kDa, type I transmembrane glycoprotein that belongs to the poliovirus receptor (PVR) family. TIGIT is expressed on activated and memory CD4+ T cells and CD8+ T cells, follicular T helper cells, regulatory T cells, and NK cells. Its ligands include the poliovirus receptor (PVR, aka, CD155), poliovirus receptor-related protein 2 (PVRL2, aka, CD112), and poliovirus receptor-related protein 3 (PVRL3, CD113). TIGIT functions as a negative regulator of T cell and NK cell responses including proliferation, cytotoxicity, and the production of proinflammatory cytokines. TIGIT-deficient mice are reportedly more susceptible to developing autoimmune diseases in certain model systems.
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.