Unexplained Primary Infertility is associated with Lack of Tight and Adherence Junction between Endometrial Cells

Abstract

The purpose of this study was to evaluate the link between protein expressions of endometrial tight junctions (TJs), adherence junctions, and vascular angiogenic precursors and in endometrial receptivity during implantation window period. Endometrial biopsies were collected during the luteal phase from unexplained infertility women and fertile women. Expressions of zona occludin-1 (ZO-1), E-cadherin (E-Cad), claudin-1 (Cla-1), and vascular angiogenic precursor (VAP) were quantified by immunohistochemical (IHC) staining. The expression of ZO-1 is markedly reduced, while expression of E-Cad and Cla-1 is absent in biopsies from unexplained infertility cases. These expressions were higher in endometrial biopsies from fertile women. The VAP expression appeared the same in patients and control. Impaired uterine cell integrity may be a key determinant of fertility in investigating endometrial quality, and predictive of receptive endometrium.