Unexplained Spontaneous Abortion Research Articles

BaP/BPDE suppresses homologous recombination repair in human trophoblast cells to induce miscarriage: The roles of lnc-HZ08

Benzo(a)pyrene (BaP) or benzo (a) pyrene 7,8-dihydrodiol-9,10-epoxide (BPDE) exposure causes trophoblast cell dysfunctions and induces miscarriage, which is generally epigenetically regulated. Homologous recombination (HR) repair of DNA double strand break (DSB) plays a crucial role in maintenance of genetic stability and cell normal functions. However, whether BaP/BPDE might suppress HR repair in human trophoblast cells to induce miscarriage, as well as its epigenetic regulatory mechanism, is largely unclear. In this study, we find that BaP/BPDE suppresses HR repair of DSB in trophoblast cells and eventually induces miscarriage by up-regulating lnc-HZ08. In mechanism, lnc-HZ08 (1) down-regulates the expression levels of FOXA1 (forkhead box A1) and thus suppresses FOXA1-mediated mRNA transcription of BRCA1 (Breast cancer susceptibility gene 1) and CtIP (CtBP-interacting protein), (2) impairs BRCA1 and CtIP protein interactions by competitive binding with CtIP through lnc-HZ08-1 fragment, and also (3) suppresses BRCA1-mediated CtIP ubiquitination without affecting CtIP stability, three of which eventually suppress HR repair in human trophoblast cells. Supplement with murine Ctip could efficiently restore (i.e. increase) HR repair and alleviate miscarriage in BaP-exposed mouse model. Collectively, this study not only reveals the association and causality among BaP/BPDE exposure, the defective HR repair, and miscarriage, but also discovers novel mechanism in lnc-HZ08-regulated BRCA1/CtIP-mediated HR repair, bridging epigenetic regulation and genetic instability and also providing an efficient approach for treatment against BaP/BPDE-induced unexplained miscarriage.

Elevated levels of KLF12 impair trophoblast syncytialization via GCM1 downregulation

Objective: Placental dysfunction is a major contributor to miscarriages in humans. We observed elevated expression of Kruppel-like factor 12 (KLF12) in placental villi of women who experienced miscarriage compared to that in women with healthy pregnancies. This study aimed to elucidate the role of KLF12 in maintaining a successful pregnancy. Methods: To investigate the role of KLF12 in placentation, we employed a model of forskolin-induced syncytialization in BeWo cells. Results: Our findings revealed that KLF12 expression is downregulated during normal syncytialization. Conversely, we observed that abnormally high KLF12 levels directly suppressed glial cells missing-1 (GCM1) expression. This suppression of GCM1 expression subsequently impaired BeWo cell syncytialization. Furthermore, we observed placental deformities in KLF12-overexpressing mouse fetuses. Conclusion: This study demonstrated that elevated levels of KLF12 disrupt trophoblast syncytialization by downregulating GCM1 expression. These findings suggest that KLF12 may be a novel candidate gene contributing to unexplained miscarriages.

P-411 CD55 deficiency hinders decidualization in unexplained early miscarriage through the Src/ERK signaling pathway

Abstract Study question What is the role of CD55 in the process of human endometrial stromal cells (HESCs) decidualization in unexplained early miscarriage? Summary answer CD55, responsive to cAMP signaling, is deficient in decidua of patients with unexplained early miscarriage, which hinders decidualization in vitro through perturbing Src/ERK signaling pathway. What is known already Decidualization is a process where HESCs differentiate into decidual stromal cells and present morphological changes and acquisition of secretory function, which is essential for embryo implantation and maintenance of pregnancy while abnormal decidualization contributed to several pregnancy disorders like a miscarriage. Reprogramming of several signaling pathways and transcription factors are involved in this process and cAMP is a critical mediator. Our previous bioinformatic analysis revealed that CD55 was upregulated over five times in the window of implantation, responding to estrogen and progesterone. We speculated that CD55, regulated by cAMP signaling pathway, might play an important role in decidualization. Study design, size, duration Decidua tissues were collected from 8 patients with unexplained early miscarriage and 10 control women with normal early pregnancy undergoing artificial abortion between June 2020 and September 2020. Immortalized HESCs line T-hESCs (ATCC CRL-4003) were cultured for up to 6 days to establish in-vitro decidualization model. Each experiment was conducted in triplicate and replicated at least three times independently. Participants/materials, setting, methods CD55 expression in control and miscarriage decidua was compared by immunohistochemistry and RT-qPCR. T-hESCs were induced into decidualization by medroxyprogesterone acetate (MPA) and 8-Br-cAMP, with prolactin (PRL) and insulin-like growth factor-binding protein 1 (IGFBP1) as decidualization biomarkers. The changes of genes and signaling pathways were detected by RT-qPCR and western blot during decidualization after CD55 knockdown by lentivirus-mediated RNA interference. Signaling pathway disruptors were added to verify the involvement of signaling pathways. Main results and the role of chance The decidua of women with unexplained early miscarriage exhibited decreased expression of CD55, accompanied by a compromised level of decidualization. During in-vitro decidualization, CD55 was significantly upregulated by cAMP in a time- and dose-dependent manner, which was attenuated by a PKA inhibitor H89. Knocking down CD55 expression diminished the expression of decidualization markers PRL and IGFBP1 through inhibition of Src, aberrant activation of ERK and frustrated expression of decidualization-related genes like FOXO1, EGFR, and STAT3. Limitations, reasons for caution The mechanisms revealed in this study were based on in-vitro cell models. It is necessary to verify the significance of CD55 in decidualization with in-vivo models to directly explain the link between CD55, decidualization, and pregnancy loss. Wider implications of the findings CD55 deficiency hinders decidualization through perturbing Src/ERK signaling pathway and expression of decidualization-related genes, potentially contributing to the pathogenesis of spontaneous miscarriage. Progestin supplementation or other factors stimulating cAMP accumulation can restore CD55 expression and improve decidualization, providing a basis for the therapy of spontaneous miscarriage. Trial registration number not applicable

BaP/BPDE exposure causes human trophoblast cell dysfunctions and induces miscarriage by up-regulating lnc-HZ06-regulated IL1B

Exposure to environmental BaP or its metabolite BPDE causes trophoblast cell dysfunctions to induce miscarriage (abnormal early embryo loss), which might be generally regulated by lncRNAs. IL1B, a critical inflammatory cytokine, is closely associated with adverse pregnancy outcomes. However, whether IL1B might cause dysfunctions of BaP/BPDE-exposed trophoblast cells to induce miscarriage, as well as its specific epigenetic regulatory mechanisms, is completely unexplored. In this study, we find that BPDE-DNA adducts, trophoblast cell dysfunctions, and miscarriage are closely associated. Moreover, we also identify a novel lnc-HZ06 and IL1B, both of which are highly expressed in BPDE-exposed trophoblast cells, in villous tissues of recurrent miscarriage patients, and in placental tissues of BaP-exposed mice with miscarriage. Both lnc-HZ06 and IL1B suppress trophoblast cell migration/invasion and increase apoptosis. In mechanism, lnc-HZ06 promotes STAT4-mediated IL1B mRNA transcription, enhances IL1B mRNA stability by promoting the formation of METTL3/HuR/IL1B mRNA ternary complex, and finally up-regulates IL1B expression levels. BPDE exposure promotes TBP-mediated lnc-HZ06 transcription, and thus up-regulates IL1B levels. Knockdown of either murine lnc-hz06 (which down-regulates Il1b levels) or murine Il1b could alleviate miscarriage in BaP-exposed mice. Collectively, this study not only discovers novel biological mechanisms and pathogenesis of unexplained miscarriage but also provides novel potential targets for treatment against BaP/BPDE-induced miscarriage.

The Relationship Between Anti-Mullerian Hormone Levels and Pregnancy Outcomes in Patients with Recurrent Unexplained Miscarriage

Background: This study aimed to assess the correlation between serum levels of anti-Mullerian hormone (AMH), basal follicle-stimulating hormone (FSH), basal luteinizing hormone (LH), and basal estradiol with pregnancy outcomes. Methods: Conducted at Shariati Hospital in Tehran from 2020 to 2021, this prospective cohort study included women under 38 years old with idiopathic recurrent miscarriage (IRM). Individuals with AMH levels below 1 ng/mL were classified as the poor responder group. All participants with IRM received a daily combination of 20 mg prednisolone and 200 mg progesterone vaginal suppositories from the beginning of pregnancy until 12 weeks, along with aspirin and folic acid. Pregnancy was monitored until 36 weeks, and outcomes were evaluated over two years using univariate and multiple logistic regression, with P-values < 0.05 considered significant. Results: The study comprised 128 individuals with a mean age of 36.4 ± 3.9 years. Of these, 80 became pregnant, while 48 did not. Among the pregnant individuals, 34 had terminations before 26 weeks (13 ongoing and 21 clinical), while 46 had pregnancies lasting 26 weeks or longer. Maternal age (RR = 1.23, 95% CI: 1.10 - 1.90, P = 0.001), history of abortion (RR = 1.262, 95% CI: 1.052 - 1.327, P = 0.008), and low serum AMH level (RR = 0.752, 95% CI: 0.227 - 0.934, P = 0.035) were significantly associated with the probability of subsequent pregnancies. Maternal age (RR = 1.108, 95% CI: 1.05 - 1.350, P = 0.025) and history of abortion (RR = 1.097, 95% CI: 1.02 - 1.161, P = 0.042) were the only factors associated with the risk of non-pregnancy. Conclusions: The study findings suggest that AMH levels in women with IRM significantly influence pregnancy outcomes, including abortion and live births at 26 weeks or more. The univariate analysis revealed significant correlations between age, serum AMH levels, previous history of abortion, and the risk of abortion. Additionally, AMH levels were found to relate to follicle storage rather than egg quality, indicating that AMH does not predict live birth after IVF. Overall, this prospective study underscores the importance of maternal age, AMH level, and previous abortion history in predicting pregnancy outcomes.

Association between concentrations of rare earth elements in chorionic villus and risk for unexplained spontaneous abortion

Rare earth elements (REEs) exposure during pregnancy may increase the risk of unexplained spontaneous abortion. However, the association between REEs intrauterine exposure and unexplained spontaneous abortion had yet to be studied. In order to conduct this large case-control study, we thus collected chorionic villus from 641 unexplained spontaneous abortion and 299 control pregnant women and detected the concentrations of 15 REEs by inductively coupled plasma mass spectrometer (ICP-MS). Because the detection rates of 10 REEs were less than 80%, the remaining 5 REEs, which were lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd) and yttrium (Y), underwent to further analysis. The association between 5 REEs and unexplained spontaneous abortion was assessed by using the logistic regression, bayesian kernel regression (BKMR) and weighted quantile sum regression (WQS) models. In the adjusted logistic regression model, Pr, Nd and Y enhanced the incidence of unexplained spontaneous abortion in a dose-dependent way and Ce increased the risk only at high concentration group. The result of BKMR model demonstrated that the risk of unexplained spontaneous abortion increased as the percentile of five mixed REEs increased. Y and Nd were both significantly associated with an increased incidence of unexplained spontaneous abortion, but La was correlated with a decrease in the risk of unexplained spontaneous abortion. Pr was substantially associated with an increase in the risk of unexplained spontaneous abortion when other REEs concentrations were fixed at the 25th and 50th percentiles. According to WQS regression analysis, the WQS index was significantly associated with unexplained spontaneous abortion (OR = 3.75, 95% CI:2.40–5.86). Y had the highest weight, followed by Nd and Pr, which was consistent with the analysis results of our other two models. In short, intrauterine exposure to REEs was associated with an increased risk of unexplained spontaneous abortion, with Y, Nd and Pr perhaps playing an essential role.

Strong association between angiotensin I-converting enzyme insertion/deletion polymorphism and unexplained recurrent spontaneous abortion of Sudanese women: a case-control study

This study investigated the link between angiotensin I-converting enzyme insertion/deletion (ACE I/D) polymorphism and unexplained spontaneous abortion. This retrospective analytical case-control was conducted at the Omdurman Maternity Hospital in Sudan. The current study contained 230 individuals, including 119 cases (women who had at least three abortions) of unknown cause and 119 controls (healthy women who had at least two full-term deliveries without spontaneous abortion). Patients and controls were provided five ml of ethylenediaminetetraacetic acid blood and answered questionnaires about their demographics, personal lives, and family histories. ACE I/D polymorphisms were assessed using a conventional polymerase chain reaction approach after total genomic DNA was isolated from blood leukocytes using the GF-1 blood DNA extraction kit. Data was analyzed using the Statistical Package for the Social Sciences version 24. ACE I/D polymorphism is strongly linked to unexplained spontaneous abortion, and women with the I/D and D/D genotypes are more likely to have it than those with the I/I genotype. The current study reveals that ACEI/D polymorphism increases pregnancy problems. Sudanese women may have spontaneous abortions due to the ACE I/D polymorphism.

Defective Homologous Recombination Repair By Up-Regulating Lnc-HZ10/Ahr Loop in Human Trophoblast Cells Induced Miscarriage.

Human trophoblast cells are crucial for healthy pregnancy. However, whether the defective homologous recombination (HR) repair of dsDNA break (DSB) in trophoblast cells may induce miscarriage is completely unknown. Moreover, the abundance of BRCA1 (a crucial protein for HR repair), its recruitment to DSB foci, and its epigenetic regulatory mechanisms, are also fully unexplored. In this work, it is identified that a novel lnc-HZ10, which is highly experssed in villous tissues of recurrent miscarriage (RM) vs their healthy control group, suppresses HR repair of DSB in trophoblast cell. Lnc-HZ10 and AhR (aryl hydrocarbon receptor) form a positive feedback loop. AhR acts as a transcription factor to promote lnc-HZ10 transcription. Meanwhile, lnc-HZ10 also increases AhR levels by suppressing its CUL4B-mediated ubiquitination degradation. Subsequently, AhR suppresses BRCA1 transcription; and lnc-HZ10 (mainly 1-447 nt) interacts with γ-H2AX; and thus, impairs its interactions with BRCA1. BPDE exposure may trigger this loop to suppress HR repair in trophoblast cells, possibly inducing miscarriage. Knockdown of murine Ahr efficiently recovers HR repair in placental tissues and alleviates miscarriage in a mouse miscarriage model. Therefore, it is suggested that AhR/lnc-HZ10/BRCA1 axis may be a promising target for alleviation of unexplained miscarriage.

Polystyrene Nanoplastics Activate Autophagy and Suppress Trophoblast Cell Migration/Invasion and Migrasome Formation to Induce Miscarriage.

Nanoplastics (NPs), as emerging pollutants, have attracted global attention. Nevertheless, the adverse effects of NPs on female reproductive health, especially unexplained miscarriage, are poorly understood. Defects of trophoblast cell migration and invasion are associated with miscarriage. Migrasomes were identified as cellular organelles with largely unidentified functions. Whether NPs might affect migration, invasion, and migrasome formation and induce miscarriage has been completely unexplored. In this study, we selected polystyrene nanoplastics (PS-NPs, 50 nm) as a model of plastic particles and treated human trophoblast cells and pregnant mice with PS-NPs at doses near the actual environmental exposure doses of plastic particles in humans. We found that exposure to PS-NPs induced a pregnant mouse miscarriage. PS-NPs suppressed ROCK1-mediated migration/invasion and migrasome formation. SOX2 was identified as the transcription factor of ROCK1. PS-NPs activated autophagy and promoted the autophagy degradation of SOX2, thus suppressing SOX2-mediated ROCK1 transcription. Supplementing with murine SOX2 or ROCK1 could efficiently rescue migration/invasion and migrasome formation and alleviate miscarriage. Analysis of the protein levels of SOX2, ROCK1, TSPAN4, NDST1, P62, and LC-3BII/I in PS-NP-exposed trophoblast cells, villous tissues of unexplained miscarriage patients, and placental tissues of PS-NP-exposed mice gave consistent results. Collectively, this study revealed the reproductive toxicity of nanoplastics and their potential regulatory mechanism, indicating that NP exposure is a risk factor for female reproductive health.

Analysis of copy number variations and possible candidate genes in spontaneous abortion by copy number variation sequencing.

Embryonic chromosomal abnormalities represent a major causative factor in early pregnancy loss, highlighting the importance of understanding their role in spontaneous abortion. This study investigates the potential correlation between chromosomal abnormalities and spontaneous abortion using copy number variation sequencing (CNV-seq), a Next-Generation Sequencing (NGS) technology. We analyzed Copy Number Variations (CNVs) in 395 aborted fetal specimens from spontaneous abortion patients by CNV-seq. And collected correlated data, including maternal age, gestational week, and Body Mass Index (BMI), and analyzed their relationship with the CNVs. Out of the 395 cases, 67.09% of the fetuses had chromosomal abnormalities, including numerical abnormalities, structural abnormalities, and mosaicisms. Maternal age was found to be an important risk factor for fetal chromosomal abnormalities, with the proportion of autosomal trisomy in abnormal karyotypes increasing with maternal age, while polyploidy decreased. The proportion of abnormal karyotypes with mosaic decreased as gestational age increased, while the frequency of polyploidy and sex chromosome monosomy increased. Gene enrichment analysis identified potential miscarriage candidate genes and functions, as well as pathogenic genes and pathways associated with unexplained miscarriage among women aged below or over 35 years old. Based on our study, it can be inferred that there is an association between BMI values and the risk of recurrent miscarriage caused by chromosomal abnormalities. Overall, these findings provide important insights into the understanding of spontaneous abortion and have implications for the development of personalized interventions for patients with abnormal karyotypes.

Research progress of immune balance and genetic polymorphism in unexplained recurrent abortion

The etiology of recurrent spontaneous abortion (RSA) is extremely complex, as there are 40–50% of patients with unexplained miscarriages, known as unexplained RSA (URSA). URSA affects approximately 1–2% of females of childbearing age and has a massive impact on the physical and mental conditions of both patients and their families. The pathogenesis of the disease remains unclear, making its treatment complicated. In recent years, considerable progress has been made in the exploration of the URSA immune balance mechanism and it has been universally acknowledged that a balanced immune response (as abnormal immunity) may be the root cause of poor pregnancy outcomes. This review discussed and summarized the effects of immune cells and blocking antibodies (BAs) on URSA based on the current state of knowledge in this area. Additionally, molecular genetics also plays an essential role in the incidence rate of URSA since the role of genetic polymorphism in the pathogenesis of URSA has been thoroughly studied. Nonetheless, the outcomes of these studies are inconsistent, particularly across populations. This paper reviewed previous studies on URSA and maternal genetic polymorphism, focusing on and synthesizing the most important findings to date, and providing diagnostic recommendation for URSA patients with clinical symptoms.

Placental Pathology Findings in Unexplained Pregnancy Losses.

There are approximately 5 million pregnancies per year in the USA, with 1 million ending in miscarriage (a loss occurring prior to 20weeks of gestation) and over 20,000 ending in stillbirth at or beyond 20weeks of gestation. As many as 50% of these losses are unexplained. Our objective was to evaluate the effect of expanding the placental pathology diagnostic categories to include the explicit categories of (1) dysmorphic chorionic villi and (2) small placenta in examining previously unexplained losses. Using a clinical database of 1256 previously unexplained losses at 6-43weeks of gestation, the most prevalent abnormality associated with each loss was determined through examination of its placental pathology slides. Of 1256 cases analyzed from 922 patients, there were 878 (69.9%) miscarriages and 378 (30.1%) antepartum stillbirths. We determined the pathologic diagnoses for 1150/1256 (91.6%) of the entire series, 777/878 (88.5%) of the miscarriages (< 20weeks' gestation), and 373/378 (98.7%) of the stillbirths (≥ 20weeks' gestation). The most common pathologic feature observed in unexplained miscarriages was dysmorphic chorionic villi (757 cases; 86.2%), a marker associated with genetic abnormalities. The most common pathologic feature observed in unexplained stillbirths was a small placenta (128 cases; 33.9%). Our classification system reinforced the utility of placental examination for elucidating potential mechanisms behind pregnancy loss. The improved rate of diagnosis appeared to be the result of filling a gap in previous pregnancy loss classification systems via inclusion of the categories of dysmorphic chorionic villi and small placenta.

MiR-146b-5p downregulates IRAK1 and ADAM19 to suppress trophoblast proliferation, invasion, and migration in miscarriage†.

A large proportion of miscarriages are classified as unexplained miscarriages since no cause is identified. No reliable biomarkers or treatments are available for these pregnancy losses. While our transcriptomic sequencing has revealed substantial upregulation of miR-146b-5p in unexplained miscarriage villous tissues, its role and associated molecular processes have yet to be fully characterized. Our work revealed that relative to samples from normal pregnancy, miR-146b-5p was significantly elevated in villous tissues from unexplained miscarriage patients and displayed promising diagnostic potential. Moreover, miR-146b-5p agomir contributed to higher rates of embryonic resorption in ICR mice. When overexpressed in HTR-8/SVneo cells, miR-146b-5p attenuated the proliferative, invasive, and migratory activity of these cells while suppressing the expression of MMP9 and immune inflammation-associated cytokines, including IL1B, IL11, CXCL1, CXCL8, and CXCL12. Conversely, inhibition of its expression enhanced proliferation, migration, and invasion abilities. Mechanistically, IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19 were identified as miR-146b-5p targets regulating trophoblast function, and silencing IL-1 receptor-associated kinase-1 had similar effects as miR-146b-5p overexpression, while IL-1 receptor-associated kinase-1 overexpression could partially reverse the inhibitory impact of this microRNA on trophoblasts. miR-146b-5p may inhibit trophoblast proliferation, migration, invasion, and implantation-associated inflammation by downregulating IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19, participating in the pathogenesis of miscarriage and providing a critical biomarker and a promising therapeutic target for unexplained miscarriage.

Gene Expression Levels of CSF-1 and CSF-1R Endometrial under The Influence of Prolactin Level in Unexplained Miscarriage: A Case-Control Study.

Hormones such as prolactin, by influencing expression of the endometrial genes, play a pivotal role in embryo implantation and development. The present study aimed to evaluate serum level of prolactin and its effect on altering expression level of colony-stimulating factor-1 (CSF-1) and colony-stimulating factor-1 receptor (CSF-1R) genes in endometrial tissue during in vitro fertilization (IVF) pregnancy in the infertile women and recurrent pregnancy loss (RPL), compared to fertile women, who lost their pregnancies at gestational age <20 weeks. In this case-control study, 40 infertile women, 40 IVF pregnant women with RPL and 40 fertile women who lost their pregnancies at <20 weeks of gestation for unknown reasons were selected. Prolactin serum level was assessed using ELISA technique and expression of CSF-1 and CSF-1R genes was determined in endometrial tissue, using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Mean prolactin level of the infertile group was 24.38 ± 1.43 ng/mL and it had statistically significant relationship with the fertile group (P<0.001). Expression level of the CSF-1 and CSF-1R genes were higher in the fertile than infertile groups by 2.88 times (P<0.0001) and 2.64 times (P<0.0001), while it was respectively 2.28 (P<0.0001) and 1.69 (P<0.0001) times higher compared to the RPL group. Risk factors for pregnancy loss, such as aging, increased body mass index (BMI), smoking and diabetes caused decreasing changes in gene expression (CSF-1 and CSF-1R ) and the differences were statistically significant, except in the infertile group. The present study showed a significant relationship of CSF-1 and CSF-1R expression levels with pregnancy loss. Risk factors such as aging, obesity, smoking and diabetes decreased both genes expression levels.

Implantation Failure/ Reccurent miscarriages- TreatmentPOSTER 5Adalimumab for recurrent miscarriages and implantation failure

IntroductionRecurrent miscarriages and implantation failures are a frequent and still unresolved clinical situation, without any recommended therapies. In euploid implantation, the impact of dys-immune reaction such as allograft rejection could raise the use of immunomodulatory therapies. TNFa antagonists were recently reported in small case series and here we present a multicenter retrospective cohort study. Patients and MethodsPatients referred to our center for unexplained miscarriages and or implantation failure and which were refractory to previous various immunomodulatory therapies (HBPM, steroids, hydroxychloroquine) received adalimumab at 40 mg every 2 weeks a month before implantation and until 9 weeks of gestation. The primary objective was the number of pregnancies with alive baby and the safety was the second objective. ResultsA total of 42 patients with implantation failure and /or recurrent miscarriage (previous number of failures 9 [4-19], received adalimumab alone or associated with other immunomodulatory therapies. Among them, 27 were pregnant and were analyzed for the efficacy of adalimumab. Among these 27 patients, 16 women (59%) experienced a pregnancy with alive baby and 11 (41%) experienced recurrent miscarriages. The number of previous failures was not significantly different between the women with recurrent miscarriages and others (11 [4-19] vs 9 [4-15]. The number of associated immunosuppressive therapies was not significantly different between women with and without recurrent failures: low molecular weight heparin in 1 and 5 cases, steroids in 5 and 12 cases, hydroxychloroquine in 2 and 6 cases, respectively. There was no case with malformation or teratogenicity in both groups and no cases of maternal serious side effect. ConclusionIn a recurrent miscarriages and implantation failures women with particular high rates of failures, adalimumab seems to allow a good rate of alive babies with a good maternal and fetal tolerance.

Paradoxical expression of NRP1 in decidual stromal and immune cells reveals a novel inflammation balancing mechanism during early pregnancy.

To investigate the balancing mechanisms between decidualization-associated inflammation and pregnancy-related immunotolerance. Decidual samples from women with normal pregnancy (n = 58) or unexplained spontaneous miscarriage (n = 13), peripheral blood from normal pregnancy and endometria from non-pregnancy (n = 10) were collected. Primary endometrial stromal cells (ESCs), decidual stromal cells (DSCs), decidual immune cells (DICs) and peripheral blood mononuclear cells (PBMCs) were isolated. The plasmid carrying neuropilin-1 (NRP1) gene was transfected into ESC for overexpression. To induce decidualization in vitro, ESCs were treated with a combination of 10nM estradiol, 100nM progesterone and 0.5mM cAMP. Anti-Sema3a and anti-NRP1 neutralizing antibodies were applied to block the ligand-receptor interactions. RNA-seq analysis was performed to identify differentially expressed genes in DSCs and DICs, and NRP1 expression was verified by Western blotting and flow cytometry. The secretion of inflammatory mediators was measured using a multifactor cytometric bead array. The effects of Sema3a-NRP1 pathway on DICs were determined by flow cytometry. Statistical differences between groups were compared using the T test and one way or two-way ANOVA. Combined with five RNA-seq datasets, NRP1 was the only immune checkpoint changing oppositely between DSCs and DICs. The decreased expression of NRP1 in DSCs allowed intrinsic inflammatory responses required for decidualization, while its increased expression in DICs enhanced tolerant phenotypes beneficial to pregnancy maintenance. DSC-secreted Sema3a promoted immunosuppression in DICs via NRP1 binding. In women with miscarriage, NRP1 was abnormally elevated in DSCs but diminished in decidual macrophages and NK cells. NRP1 is a multifunctional controller that balances the inflammatory states of DSCs and DICs in gravid uterus. Abnormal expression of NRP1 is implicated in miscarriage.

Immunohistochemical study of MMP-2, MMP-9, EGFR and IL-8 in decidual and trophoblastic specimens of recurrent pregnancy loss cases

Background and Aim: Unexplained recurrent pregnancy loss has been a a challenging research task to experts since there is no explicit pathophysiological mechanism and therefore, the treatment remains elusive. Immunological imbalance and morphological abnormalities are under investigation. This study aims to evaluate the implication of MMP-2, MMP-9, EGFR, and IL-8 in recurrent pregnancy loss cases. Materials & Methods: The study was carried out through comparison among two groups; the unexplained miscarriage group which consisted of 22 women, and the control group consisted of 18 women, who had electively terminated their pregnancies. Both groups were in the first trimester of gestation. The specimens included the trophoblast, decidua basalis, and decidua parietalis. The study was conducted via immunohistochemical methods. Antibodies were used against MMP-2, MMP-9, EGFR, and IL-8. The results were presented at a contingency table and were statistically analyzed with the Chi-Square Test (X2). Results: There were remarkable disparities in some cases in the comparison of the two groups. MMP-9 was detected significantly high in recurrent pregnancy loss (RPL) cases, both on trophoblastic and decidual specimens (p-value < .00001), MMP-2 displayed no difference among the two groups (mild to moderate detection on trophoblast and almost negative on decidual tissues). EGFR was highly detected in trophoblastic tissue (p-value = .014). IL-8 detection was particularly different in both trophoblast and decidua parietalis of the two groups (p-value < .01). Conclusion: The study revealed both morphological and immunological dysregulations that might participate in the RPL pathogenesis.

ASSOCIATION BETWEEN RECURRENT PREGNANCY LOSS AND MATERNAL THROMBOPHILIA MUTATIONS

Pregnant women with hereditary thrombophilia have an increased risk of RPL. The role of genetic thrombophilia in women with recurrent pregnancy loss have been evaluated and assumed it to be a causing factor for recurrent pregnancy loss and other reproductive complications, which includes Factor V Leiden mutation, Prothrombin, MTHFR and PAİ 4G/5G mutation. In this study we aimed to investigate the prevalence of these molecular defects in subjects with a history of early RPL. 35 women with one or more consecutive unexplained first trimester miscarriages were detected. The presence of these mutations was assessed by polymerase chain reaction analysis. We detected a combined mutation of one or more genes in 33 women, 20% of patients with at least one homozygous mutation (7 women), oonly two women (5.7%) did not have any thrombophilic mutation. These results suggest that thrombophilic mutations have an important role in etiology of RPL.

Whole exome sequencing in unexplained recurrent miscarriage families identified novel pathogenic genetic causes of euploid miscarriage.

Can whole exome sequencing (WES) followed by trio bioinformatics analysis identify novel pathogenic genetic causes of first trimester euploid miscarriage? We identified genetic variants in six candidate genes that indicated plausible underlying causes of first-trimester euploid miscarriage. Previous studies have identified several monogenic causes of Mendelian inheritance in euploid miscarriages. However, most of these studies are without trio analyses and lack cellular and animal models to validate the functional effect of putative pathogenic variants. Eight unexplained recurrent miscarriage (URM) couples and corresponding euploid miscarriages were included in our study for whole genome sequencing (WGS) and WES followed by trio bioinformatics analysis. Knock-in mice with Rry2 and Plxnb2 variants and immortalized human trophoblasts were utilized for functional study. Additional 113 unexplained miscarriages were included to identify the mutation prevalence of specific genes by multiplex PCR. Whole blood from URM couples and their <13 weeks gestation miscarriage products were both collected for WES, and all variants in selected genes were verified by Sanger sequencing. Different stage C57BL/6J wild-type mouse embryos were collected for immunofluorescence. Ryr2N1552S/+, Ryr2R137W/+, Plxnb2D1577E/+, and Plxnb2R465Q/+ point mutation mice were generated and backcrossed. Matrigel-coated transwell invasion assays and wound-healing assays were performed using HTR-8/SVneo cells transfected with PLXNB2 small-interfering RNA and negative control. Multiplex PCR was performed focusing on RYR2 and PLXNB2. Six novel candidate genes, including ATP2A2, NAP1L1, RYR2, NRK, PLXNB2, and SSPO, were identified. Immunofluorescence staining showed that ATP2A2, NAP1L1, RyR2, and PLXNB2 were widely expressed from the zygote to the blastocyst stage in mouse embryos. Although compound heterozygous mice with Rry2 and Plxnb2 variants did not show embryonic lethality, the number of pups per litter was significantly reduced when backcrossing Ryr2N1552S/+ ♂ with Ryr2R137W/+ ♀ or Plxnb2D1577E/+ ♂ with Plxnb2R465Q/+ ♀ (P < 0.05), which were in accordance with the sequencing results of Family 2 and Family 3, and the proportion of Ryr2N1552S/+ offspring was significantly lower when Ryr2N1552S/+ female mice were backcrossed with Ryr2R137W/+ male mice (P < 0.05). Moreover, siRNA-mediated PLXNB2 knockdown inhibited the migratory and invasive abilities of immortalized human trophoblasts. Besides, additional 10 variants of RYR2 and PLXNB2 were detected in 113 unexplained euploid miscarriages by multiplex PCR. The relatively small number of samples is a limitation of our study which may result in the identification of variants in unique candidate genes with no definitive although plausible causal effect. Larger cohorts are needed to replicate these findings and additional functional research is needed to confirm the pathogenic effects of these variants. Moreover, the sequencing coverage restricted the detection of low-level parental mosaic variants. For first-trimester euploid miscarriage, variants in unique genes may be underlying genetic etiologies and WES on trio could be an ideal model to identify potential genetic causes, which could facilitate individualized precise diagnostic and therapeutic regimens in the future. This study was supported by grants from the National Key Research and Development Program of China (2021YFC2700604), National Natural Science Foundation of China (31900492, 82101784, 82171648), Basic Science Center Program of the National Natural Science Foundation of China (31988101), Key Research and Development Program of Shandong Province (2021LCZX02), Natural Science Foundation of Shandong Province (ZR2020QH051), Natural Science Foundation of Jiangsu Province (BK20200223), Taishan Scholars Program for Young Experts of Shandong Province (tsqn201812154) and Young Scholars Program of Shandong University. The authors declare no conflicts of interest. N/A.

Uterine artery Doppler and Sub-Endometrial blood flow and Serum Progesterone level in patients with Unexplained Recurrent Miscarriage

Background: Unexplained Miscarriage that occurs repeatedly is still a difficult issue for couples and professionals. It affects 2–5% of females attempting to conceive and represents a considerable challenge for physicians. Aim of the Work: This study compares women who have unexplained recurrent miscarriages to healthy, fertile women in order to assess uterine artery blood flow, sub-endometrial blood flow, and serum progesterone levels in these women. Patients and Methods: At Al-Galaa Maternity Teaching Hospital, our research was carried out, and patients were divided into two groups. The case group: 50 individuals disclosed a history of recurrent, unexplained miscarriages, and the control group: 50 individuals who had at least one term birth and no history of miscarriage. Results: pulstility index of the uterine artery especially the mean value, and flow index, vascular index and vascular flow index of the endometrial and sub-endometrial area, in addition to the serum progesterone level are crucial factors in case of unexplained recurrent miscarriage. They affect unexplained recurrent miscarriage incidence significantly. The pulstility index of the uterine artery has its influence on unexplained recurrent miscarriage with 74% accuracy. The flow index has 95% accuracy, and the vascular flow index has 86% accuracy in case unexplained recurrent miscarriage. The serum progesterone level has 70% accuracy effect on unexplained recurrent miscarriage. Conclusion: the study documented that the uterine artery Doppler, endometrial and sub-endometrial blood flow level and serum progesterone level affect the incidence of unexplained recurrent miscarriage with accuracy ranging between 70% and 95%.