Application of fluorescein-labelled lectins with different glycan-binding specificities to the studies of cellular glycoconjugates in human full-term placenta.
In the present study 13 lectins of plant, fungal and animal origin, characterised by different glycan-binding specificities were used to examine the structure and distribution of specific glycans in the tissues of human placenta. Histochemical analysis was focused on villi (villous syncytiotrophoblast and stroma), cytotrophoblast of the basal plate and amniotic epithelium. It was found that glycoconjugates containing mannose and N-acetyl glucosamine were widely expressed while external fucosyl residues were absent on all studied structures of placenta. Lectins GNA (revealing non-reducing terminal mannosyl residues) and LPA (revealing sialic acid) bound selectively to the villus structures. The presence of sialic acid residues was observed in the superficial plasmalemma of syncytiotrophoblast and on the surface of the foetal capillary endothelium. Lectins LCA and PSA showed specific affinity to the plasmalemma of the cytotrophoblast and to the amniotic epithelium basement membrane. N-acetyl lactosamine-specific fungal lectin PSL selectively labelled amniotic epithelial and cytotrophoblast cell membranes and superficial plasmalemma of the syncytiotrophoblast.
D000818:Animals; D005260:Female; D019793:Fluorescein / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000378:metabolism*; D006801:Humans; D037102:Lectins / Q000378:metabolism*; D010920:Placenta / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D011134:Polysaccharides / Q000378:metabolism*; D011247:Pregnancy
D005456:Fluorescent Dyes; D037102:Lectins; D011134:Polysaccharides; D019793:Fluorescein