title: Syncytiotrophoblast membrane protein glycosylation patterns in normal human pregnancy and changes with gestational age and parturition.
abstract: The fetally derived syncytiotrophoblast in the placenta form the major interface with the maternal circulation. Cell surface N-linked oligosaccharides are known to influence cell-cell interactions in a variety of ways. The N-linked oligosaccharide component of the human syncytiotrophoblast membrane has been purified from term placentae, and its biochemical structure analysed. Ninety-five per cent of structures were complex N-linked oligosaccharides, with the remaining 5 per cent being of the oligomannose type. Seventy-two per cent of oligosaccharides were sialylated; 50 per cent having two or more sialic acid residues. Such a population of N-linked oligosaccharides would be expected to provide a surface which inhibits interactions between trophoblast and maternal leukocytes. The temporal changes in syncytiotrophoblast N-linked oligosaccharides from the end of the second, and through the third trimester (25-41 weeks) were analysed, as were the changes which occur during parturition. There was no change in the degree of sialylation of these structures. The only significant change was a 37 per cent decrease in core fucosylation of complex N-linked sugars during gestation (P less than 0.005). Women delivered by caesarean section at term, had significantly higher levels of fucosylation (equivalent to women with a gestational age of 31-36 weeks), than those who laboured at term. Present knowledge of core fucosylation of N-linked oligosaccharides is discussed in relation to trophoblast functioning.
authors.affiliation: Nuffield Department of Obstetrics, John Radcliffe Hospital, Headington, Oxford, UK.
authors.forename: P D
authors.initials: PD
authors.lastname: Arkwright
authors.forename: C W
authors.initials: CW
authors.lastname: Redman
authors.forename: P J
authors.initials: PJ
authors.lastname: Williams
authors.forename: R A
authors.initials: RA
authors.lastname: Dwek
authors.forename: T W
authors.initials: TW
authors.lastname: Rademacher
mesh_terms: D002240:Carbohydrate Sequence; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004586:Electrophoresis; D005260:Female; D005865:Gestational Age; D006031:Glycosylation; D006801:Humans; D007743:Labor, Obstetric / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000302:isolation & purification / Q000378:metabolism*; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000378:metabolism; D011247:Pregnancy / Q000502:physiology*; D014327:Trophoblasts / Q000378:metabolism*
chemical_list: D008562:Membrane Glycoproteins; D009844:Oligosaccharides