ABSTRACT
This chapter describes three different in vitro systems developed independently in different laboratories for studies of mechanisms governing the alterations of glycosylation of plasma glycoproteins: two human hepatoma cell lines, Hep 3B and Hep G2. It discusses the primary monolayer cultures of human hepatocytes, and primary cultures of mouse hepatocytes transgenic for the rat Human Alpha 1 acid Glycoprotein (AGP). Crossed-affinity immunoelectrophoresis (CAIE) with lectins and electroimmunoassay are used to determine the microheterogeneity and rate of synthesis of alpha 1-protease inhibitor and AGP secreted by the hepatocytes. As an example of the application of the systems, the effect of cytokines on glycosylation of acute-phase protein is studied. CAIE with Concanavalin A used in these in vitro systems is an excellent screening test for investigation of the regulation of the major microheterogeneity of plasma proteins. Agarose-based CAIE employing lectins as ligands has been widely used for studies of the microheterogeneity of plasma glycoproteins in disease.
