Background: Recent attention has focused on the expression of integrin molecules within the endometrium, and their relation to infertility.
Objective: The present prospective study was undertaken to determine whether the endometrium of women with unexplained infertility differs in the expression of very late activation antigens (VLA) from the endometrium of normal fertile women.
Methods: Thirty samples of endometrial biopsies from hysterectomies with non-endometrial pathology and 28 endometrial samples by uterine curetting from infertile women in secretary phase at implantation time were collected, stained with three monoclonal antibodies against β1 integrin subunits including VLA-1 to VLA-3 by immunohistochemical technique and then assessed semi-quantitatively by microscope. Chi-Square test was used to compare the expression of VLA antigens on epithelial cells, stromal cells, lymphocytes and vessels within endometrial tissues between two groups.
Results: The results showed that most VLA integrins were present in fertile and infertile endometrium tissues. There were similarities and differences in the expression of VLA molecules in different compartments. VLA-2, VLA-3 expression on endometrial compartments showed an unaltered pattern of staining during the putative window of implantation in either fertile or infertile women with no significant differences (Pvalue> 0.5). VLA-1 expression on endometrial compartments changed in fertile and unexplained infertile women, the differences were related to the presence or lack of the molecules on epithelial and stromal cells respectively.
Conclusion: Differences may explain causes of unexplained infertility, and suggests that certain integrins may participate in the cascade of molecular events leading to successful implantation and early placental development which requires more investigations.