An alpha 2 glycoprotein composed of a single polypeptide chain and present in plasma at levels of 20-55 mg/100 ml. It functions in the binding and transport of vitamin D and may also play an important role in actin homeostatis since it has been shown to bind monomeric actin with high affinity. GC-globulin also binds membranes of both circulating B and T lymphocytes. Clinically, concentrations are reduced in patients with severe liver diseases. GC-globulin may also play an important role in the mechanism of the osteomalacia that occurs with Itai-Itai disease. Prepared from plasma shown to be non reactive for HbsAG, anti-HCV, anti-HBc, and negative for anti-HIV 1 & 2 by FDA approved tests. >95percent pure by SDS-PAGE. Add deionized water to original volume, aliquot and freeze unused portion.