Insulin receptor (IR) expression in human trophoblasts of recurrent pregnancy loss (RPL)

Purpose: Insulin and glucose pathways play a key role to fetal viability and growth. The focus of the study is to investigate the potential differences of immunohistochemical expression of IR in trophoblastic and decidual cells between women who had recurrent pregnancy loss and women that underwent an abortion. Materials and methods: Trophoblastic and decidual tissues from fifty (50) women with elective abortion used as control group and from fifty (50) women with recurrent miscarriages were collected during gestational weeks 6 to 12. IR antibodies were used as immunohistochemical staining markers. Nuclear and cytoplasmic expression was evaluated. Results: No IR immunohistochemical expression was detected in both trophoblastic cells of the implantation site and deciduas basalis of the two study groups. Conclusion: The effort made to enhance our knowledge on the physiology and histology of IR expression in connection with pregnancy was halted because the results were inconclusive. While studying, though, the correlation of recurrent miscarriage with IR expression, it became evident that a lot of hormones and pathways form the weave of gestational pathology and its delicate harmony. Every piece of knowledge may clarify this still obscure field

Low expression of Progesterone Receptor A in intermediate trophoblast of miscarriages

Summary. Objective: To examine the potential differences in the expression of Progesterone Receptor A and Estrogen Receptor A in intermediate trophoblastic cells at the implantation site in elective abortions and miscarriages by immunohistochemistry. Study Design: Twenty two (22) samples of miscarriages and eighteen (18) samples of elective abortions were obtained during gestational weeks 6 to 12. Monoclonal antibodies against Cytokeratin 7 and prolactin were used to help discriminate between trophoblastic and decidual cells at the feto-maternal interface on formalin-fixed paraffin-embedded sections. Samples were then stained with ERA and PRA antibodies. Nuclear expression was considered positive. Staining intensity was measured according to a 4 grade scale. Statistical analysis of the results was performed using the Mann-Whitney test and the Wilcoxon signed rank test. Results: PRA expression in intermediate trophoblastic cells was significantly higher in elective abortions (control group) compared to miscarriages. ERA expression was uniformly negative in both groups. Conclusion: PRA expression is significantly lower in intermediate trophoblastic cells of miscarriages compared to elective abortion pregnancies. Although this could be solely a result of a secondary event, it is still an important finding in the effort to unravel the complex molecular pathobiology of spontaneous abortions