Potential mannose delivery to the mannose receptor of liver by the mannose-binding protein from Agaricus bisporus

The mannose-binding protein (MBP) of the mushroom Agaricus bisporus (Abmb) structurally belongs to the Ricin B-like type lectin (RTL) family. Abmb affinity to mannose is uncommon because MBP is usually of Collectin type lectin (CTL); RTL is mostly glucose- and/or galactose-binding proteins. Abmb is absorbable in the intestine and withstands the harsh conditions of gastrointestinal tract; therefore, it could be developed as a drug carrier for oral drug administration. In this instance, a drug molecule or nanoparticle decorated with mannosyl group could be loaded onto Abmb for enhancing its absorption in the body. Here is reported, for the first time, the potential delivery of mannose to the liver by Abmb as suggested by an in vitro observation of the mannose receptor level on the surface of liver cells.