Beschreibung:
<jats:p>Increased fucosylation of the type (sialyl) Lewis<jats:sup>x</jats:sup> was detected on the acute‐phase plasma protein α<jats:sub>1</jats:sub>‐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)‐<jats:sc>D</jats:sc>‐mannose is strongly decreased, and GDP‐<jats:sc>D</jats:sc>‐mannose is the direct precursor for GDP‐<jats:sc>L</jats:sc>‐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.</jats:p>