The 3B6 monoclonal antibody specifically recognizes the Insulin Receptor (IR), a glycoprotein composed of two extracellular α-subunits (130 kDa) and two transmembrane β-subunits (95 kDa). It is expressed on human hematopoietic and non-hematopoietic cells, but unlike the insulin-like growth factor receptor (IGF-IR), which is ubiquitous, the insulin receptor is restricted to major target tissues of insulin action. Upon binding insulin, the IR subunits form a heterotetramer of two α and two β subunits resulting in autophosphorylation and activation of the tyrosine kinase activity of the receptor. This ligand-receptor interaction is important in regulating cell metabolism and growth. 3B6/IR monoclonal antibody reacts similarly to anti-human IR α, clone 47-9, an α-subunit antibody.
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).