Glycosylation in Canine Placentas

Abstract

This article describes the carbohydrate composition of early and mature placentas from bitches, detected by lectin histochemistry. Formalin-fixed placental samples from 11 mixed-breed bitches have been assigned to the ‘early’ or the ‘mature’ placentagroup, processed by the routine histological technique and labelled with a panel of 14 biotinylated lectins. The glycan distribution was almost completely preserved over pregnancy. Cytotrophoblast cells expressed high-mannose N-linked residues andN-acetyl-D-glucosamine, whereas mannose N-linked residues, N-acetyl-D-glucosamine and β- and α-D-galactose/N-acetyl-Dgalactosamine have been found in the syncytiotrophoblast. The maternal and foetal endothelial binding pattern was enrichedin β-D-galactose, α-D-mannose in non-bisected bi/tri-antennary N-linked complex and Galα1,3Gal-Galα1,4Gal. Both deep andsuperficial glands showed a great variety of glycoconjugates, such as D-mannose, D-glucose, N-acetyl-D-glucosamine, N-acetylD-galactosamine, galactose, N-acetylneuraminic acid and fucose. Most results in this study were consistent with those previously reported in canine and feline mature placentas; here, early placentas have been analysed and the lectin binding patternof mature placentas has been further described. These studies on canine placentas contribute to detecting and understandingglycome changes in pathophysiological conditions.