Increased α3-fucosylation of α 1-acid glycoprotein in patients with congenital disorder of glycosylation type IA (CDG-Ia)

Abstract

Increased fucosylation of the type (sialyl) Lewis x was detected on the acute-phase plasma protein α 1-acid glycoprotein (AGP) in patients with the congenital disorder of glycosylation type IA. This is remarkable, because in these patients the biosynthesis of guanosine 5′-diphosphate (GDP)- D-mannose is strongly decreased, and GDP- D-mannose is the direct precursor for GDP- L-fucose, the substrate for fucosyltransferases. The concomitantly occurring increased branching of the glycans of AGP and the increased fucosyltransferase activity in plasma suggest that a chronic hepatic inflammatory reaction has induced the increase in fucosylation.