Asialofetuin 来源于胎牛血清

Asialofetuin is a glycoprotein with three asparagine-linked triantennary complex carbohydrate chains and terminal N-acetylgalactosamine residues.

Incorporation of asialofetuin (AF) in liposomes strongly enhance delivery to and endocytosis by cells displaying the AF receptor, notably hepatocytes. This provides a very efficient route for gene therapy.

Asialofetuin from fetal calf serum has been used:

• to quantitate the plant Ricin toxin′s B subunit (RTB) lectin activity in β-phaseolin signal peptide (P)–proinsulin gene (INS)–RTB plants by enzyme-linked immunosorbent assay (ELISA)
• quantitate VP7:RTB fusion protein in transformed potato tissues by ELISA
• as a glycoprotein substrate to measure the receptor-binding activity of recombinant RTB and NSP490–RTB fusion proteins
• to study the nature of the interaction between ferritin and the placenta

Asialofetuin exhibits affinity to asialoglycoprotein receptor (ASGP-R) on hepatocytes and uses the receptor to enter the cell. This property allows asialofetuin to be used as a ligand to deliver drugs to hepatocytes and as a competitive inhibitor to ASGP-R.

Prepared by a modification of Spiro, R.G., J. Biol. Chem., 235, 2860 (1960).