The 741182 monoclonal antibody specifically recognizes TIGIT (T cell Immunoreceptor with Ig and ITIM domains) which is also known as Vstm3 (V-set and transmembrane domain-containing 3), Vsig9 (V-set and Ig domain-containing 9) and WUCAM (Washington University Cell Adhesion Molecule). TIGIT is a 30-34 kDa single-pass type I transmembrane glycoprotein that belongs to the CD28 family within the Ig superfamily. TIGIT has an extracellular region with a V-type Ig-like domain, transmembrane sequence, and a cytoplasmic domain with an immunoreceptor tyrosine-based inhibitory motif (ITIM). TIGIT is expressed on NK cells and subsets of activated and memory T cells, regulatory T cells (Treg), and T follicular helper (Tfh) cells. TIGIT binds to CD112 (PVRL2/Nectin-2) and CD155 (PVR/Necl-5) that are expressed on dendritic cells (DC), endothelial cells, fibroblasts, and some tumor cells and can induce IL-10 release and inhibition of IL-12 production. Ligand-bound TIGIT downregulates TCR-mediated T cell activation and proliferation, and can block NK cell-mediated cytotoxicity.
The antibody was conjugated to BD Horizon BUV615 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome with an Ex Max near 350 nm and an Em Max near 615 nm. BD Horizon Brilliant BUV615 can be excited by the ultraviolet laser (355 nm) and detected with a 610/20 filter and a 595 nm LP. Due to the excitation of the acceptor dye by the blue/yellow-green laser line, there may be significant spillover into channels detecting PE-CF594 like emissions (eg, 610/20-nm filter).