Anti-CD81 antibodies are useful for the detection and measurement of the target protein encoded by the gene, CD81 molecule (CD81) in humans. These antibodies are used in various immunodetection applications like western blot, immunofluorescence, and flow cytometry. The canonical CD81 protein is 236 amino acids in length, 25.8 kDa in mass, and has a membrane subcellular localization. It is a member of the Tetraspanin (TM4SF) protein family. CD81 functions in integrin binding and cholesterol binding, as well as having a role in the adaptive and innate immune system. Synonyms for this protein include: CVID6; S5.7; TAPA1; TSPAN28; CD81 antigen; 26 kDa cell surface protein TAPA-1; CD81 antigen (target of antiproliferative antibody 1). Orthologs for CD81 have also been reported in other species, including mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken.