Developmental changes in carbohydrate moiety of human alpha-fetoprotein

✍ Scribed by Erkki Ruoslahti; Eva Engvall; Aulikki Pekkala; Markku Seppälä

• Book ID: 102869259
• Publisher: John Wiley and Sons
• Year: 1978
• Tongue: French
• Weight: 502 KB
• Volume: 22
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910220502

✦ Synopsis

Abstract

Human AFP purified from fetal serum and amniotic fluid was separated into three different variants by chromatography on concanavalin A insolubilized on Sepharose (Con A—Sepharose). The three variants were indistinguishable in immunodiffusion and radioimmunoassay. Sera from patients with yolk‐sac tumor and amniotic fluid from early pregnancy were found to contain a high proportion (15–45%) of AFP which does not bind to Con A, while AFP in fetal and newborn sera, and in amniotic fluid from late pregnancy, contained less (2–6%) of this variant. The use of a large excess of Con A—Sepharose and the fact that the non‐bound AFP consistently eluted as non‐bound in rechromatography showed that this AFP is non‐reactive with Con A. Fractionation of radiolabelled AFP from cord serum in a mixture with amniotic fluid verified the difference in the amount of the Con‐A non‐reactive variant in AFP from these two sources. These results suggest that AFP synthesized by the yolk‐sac tissue and by the liver are glycosylated differently. The variant may prove to be diagnostically useful.