Affinity purified Wisteria floribunda agglutinin or lectin (WFA/WFL) is composed of four subunits. This lectin is not blood group specific although it does react stronger with human type A1 cells over A2, B, or O cells. The presence of a sialic acid residue may cause a lack of WFA reactivity. WFA contains a strong hemagglutinin activity and is a potent mitogen, both strongly inhibited by GalNAc, although mitogenic activity is also inhibited by N,Nâ€™-diacetylchitobiose.Horseradish peroxidase (HRP) is a 40 kDa protein that catalyzes the oxidation of substrates by hydrogen peroxide, resulting in a colored or fluorescent product or release of light as a byproduct of the reaction. It is most commonly used for blotting, immunoassays and immunohistochemistry methods. Wisteria floribunda Lectin (WFA/WFL) is conjugated to HRP at an appropriate ratio to provide optimal staining characteristics.