Expression of peroxisome proliferator activation receptors (PPARs) and TNFα in placenta tissues in unexplained recurrent pregnancy loss: an immunohistochemical study.

INTRODUCTION: PPAR expression in placenta tissues regulates proinflammatory cytokine production and preserves the quiescence of the uterus during pregnancy. PPAR-γ regulates inflammatory response during gestation while PPAR-δ and TNFα play a central role at implantation, decidualization and placentation. However, their expression levels affect normal pregnancy and may cause gestational complications and miscarriage. The aim of this report is to investigate the relationship of these molecules with unexplained recurrent miscarriage. MATERIALS-METHODS: The miscarriage group was obtained from 12 women, between the ages of 35 to 42 years, who miscarried during the 1st trimester of gestation and controls consisted of 12 healthy women, between the ages of 27 to 39 years, who had electively terminated their pregnancies, during the 1st trimester of gestation. The abortion material was processed and specimens taken were studied using immunohisto-chemical methods. Specimens were taken from decidua basalis and decidua parietalis. Monoclonal antibodies were used against PPAR-γ (Peroxisome Proliferator Activation Receptor γ), PPAR-δ and TNFα (Tumor Necrosis Factor alpha). The results were statistically analyzed with Mann-Whitney test. RESULTS: Our research identified PPAR-γ expression in decidua basalis and decidua parietalis from control group and decidua basalis from miscarriage group. PPAR-δ expression was also identified in both deciduas from both groups. Statistically, no significant change in PPAR-γ and PPAR-δ expression was observed between recurrent miscarriage group and controls. On the contrary, a statistically significant upregulation of TNFα was identified in both deciduas between miscarriage group and controls (p<0.05). CONCLUSIONS: Our evidence did not support a possible role of PPARs expression in recurrent pregnancy loss. However, a potential involvement of TNFα in the syndrome was reported. Further research should be performed due to insufficient bibliographic data.

Immunohistochemical study of immunological markers: HLAG, CD16, CD25, CD56 and CD68 in placenta tissues in recurrent pregnancy loss.

INTRODUCTION: Recurrent pregnancy loss (RPL) of unknown etiology is correlated with immunological alterations during pregnancy. Normally, changes in leukocyte subpopulations and HLA expression take place in pregnant uterus in order to tolerate the semi-allogenic embryo. OBJECTIVE: Our research tries to enlighten the immunological changes that take place in the uterus of women with recurrent abortions of unknown etiology during first trimester of pregnancy. MATERIALS AND METHODS: The miscarriage group was obtained from 25 women who miscarried between the ages of 35 to 42 years and controls consisted of 25 healthy women between the ages of 27 to 39 years, who had electively terminated their pregnancies during the first trimester of pregnancy. The abortion was processed and specimens taken were studied using immunohistochemical methods. Specimens were taken from decidua basalis and decidua parietalis. Monoclonal antibodies were used against HLAG (Human Leukocyte Antigen G), CD68( Cluster of Differentiation 68), CD56, CD16 and CD25. The results were statistically analysed with Mann-Whitney test. RESULTS: HLA-G expression in decidua basalis from miscarriage group was found to be decreased. CD25+ cell expression was found to be invariable in deciduas from both groups. CD16+ cell and CD68 + cell expression was found to be increased in deciduas from the miscarriage group. CD56+ cell expression was found to be increased in decidua parietalis from miscarriage group. Conclusion : Several differences in the immunological profile of deciduas from RPL group were observed. Changes in feto-protective HLA-G expression and a possible implication of macrophages and NK cells were found.

Low expression of progesterone receptor A in intermediate trophoblast of miscarriages.

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.