Expression of the carbohydrate antigens Sialyl Lewis a, Sialyl Lewis x and Lewis x in the placentae of patients with miscarriages

Objectives To analyse the expression patterns of different carbohydrate antigens (Sialyl-Lewis-a (sLeA), Sialyl-Lewi- x (sLeX) and Lewis-x (LeX)) in placental tissues of patients suffering from miscarriages.

Patients and methods Paraformaldehyde fixed and paraffin-embedded placental tissue samples of women suffering from spontaneous (n = 19) and recurrent miscarriage (n = 20) were analysed using immunohistochemistry. Samples from normal pregnancies served as controls.

Results While staining of sLeA and sLeX was detected in the syncytiotrophoblast and decidua of all groups, the expression in decidual tissue was restricted to the surface and gland epithelium, while the stroma cells remained unstained.

SLeA was significantly downregulated in the syncytiotrophoblast of spontaneous and recurrent miscarriages (p < 0.0001 and p = 0.0058, respectively), but showed no difference in decidua (p = 0.0750 and p = 0.2901). Similarly, sLeX was significantly downregulated in both miscarriage groups (p = 0.0171 and p = 0.0011) without an apparent difference in decidua (p = 0.0606 and p = 0.1200). While no staining of LeX was identified in the syncytiotrophoblast of the spontaneous-miscarriage-group, its expression in decidua was unaltered (p = 0.4669). Expression of LeX was also downregulated in the syncytiotrophoblast of the recurrent-miscarriage-group (p = 0.0035) but prominently upregulated in decidua compared to controls and spontaneous miscarriages (p = 0.0046 and 0.0013). Strikingly, LeX staining was also identified in the endothelial cells of both fetal and maternal blood vessels.

Conclusions The expression patterns of the investigated carbohydrate antigens in the placentae of miscarriage patients differed significantly from those during normal pregnancies. These novel insights may contribute to understanding the intriguing molecular interplay at the feto-maternal interface during normal pregnancy and miscarriages.

Interessenkonflikt

Es bestehen keine Interessenkonflikte.

Publikationsverlauf

Artikel online veröffentlicht:
07. Oktober 2020