Visual identification of three kinds of human decidual tissues from elective termination of pregnancy.

INTRODUCTION: The decidua can be classified into the decidua basalis, decidua capsularis and decidua parietalis. This study aimed to visually identify these three kinds of decidual tissues from fresh samples obtained in early pregnancy based on their macroscopic appearances, which can be discerned visually. METHODS: Decidual samples were collected from 15 pregnant women between 6 and 8 weeks of gestation after elective termination of pregnancy. We identified the three different kinds of fresh decidual tissues in early pregnancy according to their different macroscopic appearances by only the naked eye. H&E staining, in situ immunofluorescence and flow cytometry were performed to confirm the accuracy of this method. RESULTS: We developed a method to discern the three different kinds of decidual tissues according to their individual macroscopic features. We found that the decidua parietalis was a thick tissue with less blood, with one side being intact epidermis and the other side being rough tissue. The decidua basalis had rough surfaces, a dense texture and high blood content. The decidua capsularis was a thin membrane tissue with or without blood clots. CK+/HLA-G+ extravillous trophoblast cells (EVTs) and heme oxygenase-1+ (HMOX1+) decidual macrophages were present in large quantities in the decidua basalis and decidua capsularis but were nearly undetectable in the decidua parietalis. We also found a wide distribution of endovascular extravillous trophoblast cells (enEVTs), which participate in spiral artery remodelling in the decidua basalis. DISCUSSION: We successfully identified three kinds of human decidual tissues from early pregnancy with the naked eye for the first time. This breakthrough method will greatly assist studies related to decidua during early pregnancy.

Decidual-tissue-resident memory T cells protect against nonprimary human cytomegalovirus infection at the maternal-fetal interface.

Congenital cytomegalovirus (cCMV) is the most common intrauterine infection, leading to infant neurodevelopmental disabilities. An improved knowledge of correlates of protection against cCMV is needed to guide prevention strategies. Here, we employ an ex vivo model of human CMV (HCMV) infection in decidual tissues of women with and without preconception immunity against CMV, recapitulating nonprimary vs. primary infection at the authentic maternofetal transmission site. We show that decidual tissues of women with preconception immunity against CMV exhibit intrinsic resistance to HCMV, mounting a rapid activation of tissue-resident memory CD8+ and CD4+ T cells upon HCMV reinfection. We further reveal the role of HCMV-specific decidual-tissue-resident CD8+ T cells in local protection against nonprimary HCMV infection. The findings could inform the development of a vaccine against cCMV and provide insights for further studies of the integrity of immune defense against HCMV and other pathogens at the human maternal-fetal interface.

Comprehensive RNA expression profile analysis of γδ T cells from peripheral blood and decidual tissues in normal pregnancy (NP) donors and patients with recurrent pregnancy loss (RPL).

Recurrent pregnancy loss (RPL) is a significant adverse pregnancy complication. The loss of immune tolerance has been proposed in the pathogenesis of RPL, however, the role of γδ T cells in RPL is still controversial. In this study, the gene expression patterns of circulated and decidual tissue-resident γδ T cells from normal pregnancy donors and patients with RPL were analyzed by SMART-seq. We demonstrate that the transcriptional expression profile of different subsets of γδ T cells in peripheral blood and decidual tissue is strikingly different. Vδ2 γδ T cells, as the major cytotoxic subset, are found to be enriched considerably, and the potential cytotoxicity of this subset is further enhanced in the decidua of RPL patients may be due to detrimental ROS reduction, enhanced metabolic activity, downregulation of immunosuppressive molecules expression in resident γδ T cells. Time-series Expression Miner (STEM) analysis of transcriptome indicates complex changes in gene expression in decidual γδ T cells over time from NP and RPL patients. Taken together, our work identifies high heterogeneity of gene signature in γδ T cells from NP and RPL patients between peripheral blood and decidua, which will be a useful resource for further studies of the critical roles of γδ T cells in RPL.

THE INHIBITORY EFFECT OF PROSTAGLANDIN E_2 ON THE HUMAN DECIDUAL TISSUES CULTURED IN VITRO / 中国药理学通报

PGF2. What we observsd suggests that PGE2 has the ability to inhibit the decidual cells directly; neither the contraction of the uterus nor the metabolism of estrogen or progestogen may be responsible for this effect. This inhibitory effect of PGE2 on decidual cells may be one of the mechanisms for the termination of the early pregnancy.