Human CD81 PharmaGenie ELISA Kit (SBRS0399)

CD81, also known as TAPA-1, is a member of the tetraspanin family of transmembrane proteins. It is broadly expressed across immune cell types and contributes to lymphocyte activation, immune synapse formation, and B cell signaling through its incorporation into the CD19/CD21 coreceptor complex. CD81 additionally functions as a key host-cell entry receptor for hepatitis C virus and is widely employed as a surface marker for small extracellular vesicles, including exosomes. The Assay Genie immunoassay supports quantitative measurement of this clinically relevant tetraspanin in human biological specimens for in vitro research applications.