Distinct pattern of Th17/Treg cells in pregnant women with a history of unexplained recurrent spontaneous abortion

Shoutai Wan treatment upregulates the expression of TNFAIP3 and improves T cell immune tolerance at maternal-fetal interface

Shoutai Wan (STW) is a traditional Chinese medicine formula used to treat various conditions. The objective of this study was to evaluate the impact of STW on the abortion rate in the URSA mouse model and elucidate its underlying molecular mechanisms. Female CBA/J mice were mated with male DBA/2 mice to establish the URSA model. Network pharmacological analysis was employed to investigate the potential molecular mechanisms of STW. Hematoxylin-eosin staining, immunofluorescence, and ELISA were performed to examine placental microenvironmental changes, protein expression related to TNFAIP3 and the NF-κB signaling pathway. Treatment with STW reduced the abortion rate in URSA model mice and improved trophoblast development. TNFAIP3 was identified as a potential target of STW for treating URSA, as STW enhanced TNFAIP3 protein expression while decreasing IL-6 and TNF-α secretion in the placenta. Moreover, STW upregulated TNFAIP3 protein expression and Foxp3 mRNA levels, increased the production of anti-inflammatory cytokines such as IL-10 and TGF-β1, and decreased p-NF-κB expression in CD4+ cells at the placenta. The findings of this study indicate that STW treatment reduces the abortion rate in the URSA mouse model. These effects are likely mediated by increased TNFAIP3 expression and decreased NF-κB signaling pathway activity at the maternal-fetal interface. These molecular changes may contribute to the regulation of T cell immunity and immune tolerance during pregnancy.

Recombinant humanized type I collagen remodels decidual immune microenvironment at maternal-fetal interface by modulating Th17/Treg imbalance

Disruption of the extracellular matrix and dysregulation of the balance between Th17 and regulatory T cells are recognized as risk factors for recurrent spontaneous abortion (RSA). However, the interaction between matrix components and the Th17/Treg axis remains poorly elucidated. The result of this study revealed that the absence of type I collagen in the decidua is linked to Th17/Treg imbalance in RSA. Furthermore, we discovered that biomaterial recombinant humanized type I collagen (rhCOLI) promoted T cell differentiation into Tregs by inhibition the Notch1/Hes1 signaling pathway and enhanced the immunosuppressive function of Tregs, as indicated by increased secretion level of IL-10 and TGF-β. Importantly, this study is the first to demonstrate that rhCOLI can modulate the Th17/Treg imbalance, reduce embryo resorption rates, reshape the immune microenvironment at the maternal-fetal interface, and improve fertility in an RSA mouse model. Collectively, these findings suggest that type I collagen deficiency may contribute to, rather than result from, RSA, and propose a potential intervention for RSA using rhCOLI.

Intravenous immunoglobulin improves live birth rates in patients with unexplained recurrent pregnancy loss

This real-world study aimed to assess the clinical efficacy and safety of intravenous immunoglobulin (IVIG) in treating unexplained recurrent pregnancy loss (uRPL) patients. A total of 238 patients with uRPL were enrolled in this retrospective study. According to the treatment, patients were assigned into treatment group (n=184, receiving IVIG+low molecular weight heparin [LMWH]) and control group (n=54, only LMWH). The primary outcome was the live birth rates (LBR) after 24 weeks of gestation. In addition, we performed subgroup analyses to assess the LBR in uRPL patients with age (≥30 years or <30 years), body mass index (BMI, 18-24 kg/m2 or ≥24 kg/m2), number of previous pregnancy losses (2 or ≥3), gestational week of first medication, and IVIG medication regimen during pregnancy. The LBR showed a significant increase after IVIG treatment compared to the control group (77.7 % vs. 53.7 %, P=0.001). Multivariable logistic regression indicated that IVIG was associated with increased LBR (aOR=4.383, 95 %CI 2.024-9.489). Besides, we observed a significantly lower incidence of decreased platelet count (1.6 % vs. 7.4 %, P=0.049) in the treatment group. Subgroup analyses showed that IVIG treatment was associated with improved LBR in uRPL patients with age of <30 years (aOR=4.012, 95 %CI 1.428-11.266), previous pregnancy losses ≥3 times (aOR=17.327, 95 %CI 2.525-118.921), and BMI of 18-24 kg/m2 (aOR=8.914, 95 %CI 2.985-26.618). IVIG treatment significantly improves the LBR in uRPL patients. These findings from real-world data provide evidence for the safety and efficacy of IVIG as a viable treatment for uRPL patients in clinical practice.

Causal Relationship Between Circulating Immune Cells and Recurrent Spontaneous Abortion: A Bidirectional Mendelian Randomization Study

BACKGROUND

Recurrent spontaneous abortion (RSA) is a serious and common complication of pregnancy caused by multiple factors. The etiology remains incompletely understood, but immunologic factors play important roles. Here, we aimed to evaluate whether circulating immune cells causally impacted RSA.

METHODS

In this study, we conducted a comprehensive two-sample Mendelian randomization (MR) study to determine the causal association between the 731 immunophenotypes of human peripheral blood lymphocytes and the number of spontaneous abortions as well as recurrent miscarriage. Sensitivity analyses were performed to assess and minimize heterogeneity and horizontal pleiotropy. Reverse MR analysis was used to assess reverse causality.

RESULTS

After Bonferroni-correction, eight immunophenotypes were significantly associated with the number of spontaneous abortions: FSC-A on CD4+ T cell (beta = -0.051, 95% CI = [-0.085, -0.017], P-value = 0.004), CD8 on HLA DR+ CD8+ T cell (beta = -0.040, 95% CI = [-0.067, -0.014], P-value = 0.003), HLA DR on CD33dim HLA DR+ CD11b- (beta = -0.021, 95% CI = [-0.036, -0.005], P-value = 0.010), HLA DR+ T cell Absolute Count (beta = 0.022, 95% CI = [0.006, 0.037], P-value = 0.008), HLA DR+ T cell % lymphocyte (beta = 0.026, 95% CI = [0.010, 0.041], P-value = 0.001), HLA DR+ T cell % T cell (beta = 0.023, 95% CI = [0.007, 0.039], P-value = 0.004), HLA DR+ CD4+ T cell % lymphocyte (beta = 0.034, 95% CI = [0.007, 0.060], P-value = 0.012), and HLA DR on B cell (beta = 0.012, 95% CI = [0.003, 0.021], P-value = 0.010). In addition, we identified two immunophenotypes associated with recurrent miscarriage: HLA DR on B cell (OR = 0.854, 95% CI = [0.757, 0.964], P-value = 0.011), and CD19 on naive-mature B cell (OR = 4.595, 95% CI = [1.674, 12.617], P-value = 0.003). There was no evidence of heterogeneity, horizontal pleiotropy and reverse causality.

CONCLUSIONS

Our study demonstrated a tight link between adaptive immune cells and RSA through genetic means, thus providing potential therapeutic targets or novel diagnostic biomarkers.

Regulatory T Cell and T Helper 17 Cell Imbalance in Patients with Unexplained Infertility

Purpose

Female infertility is a global health concern. The aim of this study was to investigate the relationship between regulatory T (Treg) cells and helper T cells 17 (Th17) in peripheral blood and unexplained infertility (UI). In addition, we explored potential valuable diagnostic biomarkers for patients with UI and ascertained whether Treg and Th17 cells are associated with primary and secondary UI.

Patients and Methods

The patients underwent standard fertility evaluation test, including blood tests, ultrasound examination, fallopian tube tests, ovulation assessment, and male partner's semen analysis. According to the inclusion and exclusion criteria, this study enrolled 37 patients with UI (30 with primary UI and 7 with secondary UI) and 26 age-matched healthy volunteers as the control group. Flow cytometry was used to detect the frequency of Treg and Th17 cells. The area under the receiver operating characteristic curve (AUC) with a 95% confidence interval (CI) was used to assess the diagnostic performance. An AUC > 0.800 indicated good diagnostic performance.

Results

The percentage of Treg decreased significantly, whereas the percentage and absolute count of Th17 cells increased. Moreover, the Th17/Treg ratio in patients with UI increased significantly. As a diagnostic biomarker for UI, the Th17/Treg ratio exhibited remarkable diagnostic performance (AUC: 0.813 (95% CI = 0.709-0.917)). However, the percentages and absolute counts of Treg and Th17 cells in the peripheral blood of women with primary and secondary UI, as well as their Th17/Treg ratios, did not differ significantly.

Conclusion

The distribution of Treg and Th17 cells is imbalanced in patients with UI. Therefore, the Th17/Treg ratio may be a promising indicator of UI. However, there were no significant differences in the distribution of Treg and Th17 cells between women with primary and secondary UI.

GRIM-19 deficiency promotes macrophage polarization to the M1 phenotype partly through glycolysis in unexplained recurrent spontaneous abortion†

The occurrence of unexplained recurrent spontaneous abortion (URSA) is closely related to immune system disorders, however, the underlying mechanisms remain unclear. The purpose of this study was to investigate the expression of GRIM-19 in URSA and the possible pathogenesis of URSA according to macrophage polarization. Here, we showed that GRIM-19 was downregulated in the uterine decidual macrophages of patients with URSA and that GRIM-19 downregulation was accompanied by increased M1 macrophage polarization. Furthermore, the expression levels of glycolytic enzymes were substantially enhanced in the uterine decidual macrophages of URSA patients, and glycolysis in THP-1-derived macrophages was further enhanced by the downregulation of GRIM-19. Additionally, the increase of M1 macrophages resulting from the loss of GRIM-19 was significantly reversed in cells treated with 2-deoxy-D-glucose (2-DG, an inhibitor of glycolysis). To provide more direct evidence, GRIM-19 deficiency was shown to promote macrophage polarization to the M1 phenotype in GRIM-19+/- mouse uteri. Overall, our study provides evidence that GRIM-19 deficiency may play a role in regulating macrophage polarization in URSA, and that glycolysis may participate in this process.

The evaluation of PD-1 and Tim-3 expression besides their related miRNAs in PBMCs of women with recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a multifactorial disorder, associated with immunologic abnormalities. During pregnancy, the maternal immune system uses different tolerance mechanisms to deal with a semi-allogenic fetus. The expression of immune checkpoints and their related miRNAs in immune cells can ensure pregnancy at the feto-maternal interface by modulating immune responses. This study aims to evaluate the expression of the immune checkpoint molecules PD-1 and Tim-3 on circulating T cells by flow cytometry, that of mir-138 and mir-155 in PBMCs by Real-time PCR, and the concentrations of TGF-β and IP-10 in the sera of women suffering from RPL as well as of gestational age-matched healthy pregnant women by ELISA. The percentage of PD-1 or Tim-3 expressing CD8+ T cells was significantly lower in RPL patients compared to the controls, while there was no significant difference in Tim-3 expression of CD4+ T cells between the two groups. The mRNA of both the PD-1 and Tim-3 genes were downregulated in PBMCs of RPL patients compared to controls, however, the difference was not statistically significant for Tim-3. The concentration of TGF-β was significantly lower and that of IP-10 was significantly higher in the sera of RPL patients than in those of the controls. The relative expression of mir-138 and miR-155 were significantly lower, in PBMCs of RPL patients than in those of healthy pregnant women. These data confirm that by affecting cytokine production, immune checkpoints, and microRNAs play a role in establishing the appropriate local immune environment for successful pregnancy. The wider analysis of immune checkpoints may also yield new biomarkers for the diagnosis and prevention of RPL.

FTO protein regulates the TGF-β signalling pathway through RNA N6-methyladenosine modification to induce unexplained recurrent spontaneous abortion

Recent studies have revealed the involvement of RNA m6A modification in embryonic development; however, the relationship between aberrant RNA m6A modification and unexplained recurrent spontaneous abortion (URSA) remains unclear. In this study, we analysed the level of RNA m6A modification in trophoblasts using dot blot, RNA m6A quantification, and MeRIP assays. By integrating data from the GEO database, RNA-Seq, and MeRIP-Seq, we examined the aberrant expression of m6A methyltransferases and their downstream molecules in chorionic villus (placental) tissues. RNA pull-down, RIP, and electrophoretic mobility shift assay were used to analyse the binding relationship between the YTHDC1 protein and MEG3. Additionally, RNA stability and BrU immunoprecipitation chase assays were utilised to elucidate the regulation of MEG3 stability by YTHDC1. ChIP and DNA pull-down RNA experiments were performed to elucidate the mechanism by which MEG3 targets EZH2 to the TGF-β1 promoter. The results showed that the expression of the m6A demethylase FTO protein was significantly increased in URSA trophoblasts, leading to inhibition of the MEG3 m6A modification and weakening of the stabilising effect of the m6A binding protein YTHDC1 on MEG3. Furthermore, MEG3 was found to bind simultaneously with the EZH2 protein and the TGF-β1 gene promoter, enabling the localisation of EZH2 protein to the TGF-β1 gene promoter and subsequent inhibition of TGF-β1 gene expression. In summary, our findings elucidate the mechanism by which FTO protein regulates the MEG3-TGF-β signalling pathway, thereby suppressing trophoblast invasion and proliferation in URSA trophoblast cells. These findings provide new insights for the treatment of URSA.

Meta-analysis of FOXP3 polymorphisms and recurrent spontaneous abortion susceptibility

BACKGROUND

The polymorphisms of the FOXP3 gene may mediate abnormalities in Tregs, leading to an imbalance in maternal-fetal immune tolerance and ultimately resulting in recurrent spontaneous abortion (RSA). This meta-analysis aims to assess the potential association between FOXP3 polymorphisms and susceptibility to RSA using five specific single nucleotide polymorphisms (SNPs).

MATERIALS AND METHODS

By conducting a comprehensive search across databases such as EMBASE, PubMed, Web of Science, Cochrane Library, CNKI, Wanfang, and CBM, we identified suitable studies for inclusion in the meta-analysis. The data extracted from these studies were subjected to analysis using Stata SE 15. To assess the degree of association, we utilized the odds ratio (OR) along with its corresponding 95% confidence intervals (CI). Five specific single nucleotide polymorphisms (SNPs) were employed in assessing the connection between FOXP3 gene polymorphisms and RSA.

RESULTS

The meta-analysis demonstrated a significant association between several polymorphisms (rs3761548, rs2232365, rs2232368, rs2280883, and rs2294021) and susceptibility to RSA. Conversely, the FOXP3 rs5902434 polymorphism was not associated with susceptibility to RSA.

CONCLUSION

Our meta-analysis suggests that these genetic variations within the FOXP3 gene might play a role in the progression of RSA disease. Meanwhile, large-scale studies that consider multiple factors are needed to validate this finding.

Kisspeptin prevents pregnancy loss by modulating the immune microenvironment at the maternal-fetal interface in recurrent spontaneous abortion

PROBLEM

Immune factors are crucial in the development of recurrent spontaneous abortion (RSA). This study aimed to investigate whether kisspeptin regulates immune cells at the maternal-fetal interface and whether G protein-coupled receptor 54 (GPR54) is involved in this process, through which it contributes to the pathogenesis of RSA.

METHOD OF STUDY

Normal pregnancy (NP) (CBA/J × BALB/c) and RSA (CBA/J × DBA/2) mouse models were established. NP mice received tail vein injections of PBS and KP234 (blocker of kisspeptin receptor), whereas RSA mice received PBS and KP10 (active fragment of kisspeptin). The changes in immune cells in mouse spleen and uterus were assessed using flow cytometry and immunofluorescence. The expression of critical cytokines was examined by flow cytometry, ELISA, Western blotting, and qPCR. Immunofluorescence was employed to detect the coexpression of FOXP3 and GPR54.

RESULTS

The findings revealed that the proportion of Treg cells, MDSCs, and M2 macrophages in RSA mice was lower than that in NP mice, but it increased following the tail vein injection of KP10. Conversely, the proportion of these cells was reduced in NP mice after the injection of KP234. However, the trend of γδT cell proportion change is contrary to these cells. Furthermore, FOXP3 and GPR54 were coexpressed in mouse spleen and uterus Treg cells as well as in the human decidua samples.

CONCLUSION

Our results suggest that kisspeptin potentially participates in the pathogenesis of RSA by influencing immune cell subsets at the maternal-fetal interface, including Treg cells, MDSC cells, γδT cells, and M2 macrophages.

Differentiation of T cells producing interleukin-17 (Th17) against the background of exogenous melatonin during pregnancy

The population of T lymphocytes producing IL-17 (Th17) plays a dual role during pregnancy and its activity is tightly controlled during this period. One of the factors involved in this process may be the pineal hormone melatonin, which can effectively regulate this T cell population. Here we have shown that exogenous melatonin in pharmacological concentrations is able to enhance the differentiation of Th17 cells of pregnant women in vitro. The stimulatory effects of melatonin were limited to in the first trimester of pregnancy and were apparently mediated by both membrane and nuclear melatonin receptors. Since exogenous melatonin is currently considered as a promising drug in solving various problems associated with reproduction, it is necessary to take into account its immunoregulatory effects.

The role of Th17 and Treg cells in normal pregnancy and unexplained recurrent spontaneous abortion (URSA): New insights into immune mechanisms

Recurrent spontaneous abortion (RSA) has various causes, including chromosomal abnormalities, a prethrombotic state, and abnormal uterine anatomical factors. However, in about 50% of cases, the cause remains unknown and is referred to as unexplained recurrent spontaneous abortion (URSA). The fetus is protected from rejection by the maternal system, acting as an allogeneic gene, and immune tolerance serves as a crucial mechanism. The Th17/Treg cell paradigm's emergence as a new subpopulation of CD4+ T cells, interacting with one another, plays an essential role in the immune microenvironment and the body's defense system. This Th17/Treg cell model helps to explain the pathology of recurrent miscarriage that could not be accounted for by the original immune mechanism based on the Th1/Th2 model. Furthermore, the plasticity of Th17 and Treg cells holds innovative significance in autoimmunity and abortion. This paper reviews the role of Th17/Treg cellular immune response in the maintaining normal pregnancy and understanding unexplained recurrent spontaneous abortion.

Th17 / Treg ratio: A prospective study in a group of pregnant women with preeclampsia and fetal growth restriction

INTRODUCTION

During pregnancy, the maternal immune system is challenged to tolerate a semi-allogenic fetus. A proinflammatory profile has been linked to adverse pregnancy outcomes and poor placental development. In this study, the authors evaluated the number of circulating Tregs and Th17 cells in a group of patients diagnosed with preeclampsia(PE) and fetal growth restriction(FGR).

METHODS

Prospective longitudinal observational study where peripheral blood lymphocyte subsets were analyzed in a cohort of pregnant patients with PE, FGR, and a control group of healthy pregnant women.

RESULTS

The diagnosis of PE was associated with a significative higher number of circulating Th17 cells and a significative relative reduction in the Treg cell count. This proinflammatory profile was also expressed in the evolution of the Th17/ CD4+CD25highFOXP3+ Treg ratio. In the FGR group, the Th17 cell count was significantly higher during the third trimester of pregnancy. This proinflammatory profile was also expressed in the evolution of the Th17/ CD4+CD25highFOXP3+ Treg ratio. When we compare the immunological profiles of patients with PE and FGR we observed a higher number of proinflammatory Th17 cells and a significative lower number of Treg cells in PE patients. This is particularly expressed in the differences found between the Th17/ CD4+CD25highFOXP3+ Treg ratios of these two groups. Discussion/Conclusion Our data showed a that a proinflammatory profile and a relative excess of Th17 cells was associated with the diagnosis of PE and FGR. A more exuberant systemic proinflammatory profile present in the PE patients is absent in patients with FGR without preeclampsia.

Omega-3 fatty acid supplements and recurrent miscarriage: A perspective on potential mechanisms and clinical evidence

Recurrent miscarriage (RM) affects approximately 1%-5% of couples worldwide. Due to its complicated etiologies, the treatments for RM also vary greatly, including surgery for anatomic factors such as septate uterus and uterine adhesions, thyroid modulation drugs for hyperthyroidism and hypothyroidism, and aspirin and low molecular weight heparin for antiphospholipid syndrome. However, these treatment modalities are still insufficient to solve RM. Omega-3 fatty acids are reported to modulate the dysregulation of immune cells, oxidative stress, endocrine disorders, inflammation, etc., which are closely associated with the pathogenesis of RM. However, there is a lack of a systematic description of the involvement of omega-3 fatty acids in treating RM, and the underlying mechanisms are also not clear. In this review, we sought to determine the potential mechanisms that are highly associated with the pathogenesis of RM and the regulation of omega-3 fatty acids on these mechanisms. In addition, we also highlighted the direct and indirect clinical evidence of omega-3 fatty acid supplements to treat RM, which might encourage the application of omega-3 fatty acids to treat RM, thus improving pregnancy outcomes.

The Importance of Metabolic and Environmental Factors in the Occurrence of Oxidative Stress during Pregnancy

Metabolic changes in pregnant women begin in the first weeks after conception under the influence of placental hormones that affect the metabolism of all nutrients. An increased concentration of total lipids accompanies pregnancy and an increased accumulation of triglycerides in low-density lipoproteins (LDL) particles. Lipids in small dense LDL particles are more susceptible to oxidative modification than normal-density LDL particles. Unlike LDL high-density lipoproteins (HDL), lipoprotein particles have an atheroprotective role in lipid metabolism. The very growth of the fetus depends on the nutrition of both parents, so obesity is not only in the mother but also in the father. Nutritional programming of the offspring occurs through changes in lipid metabolism and leads to an increased risk for cardiometabolic diseases. Pregnancy is accompanied by an increased need for oxygen in the mitochondria of the placenta and a tendency to develop oxidative stress. Oxidative stress represents a disturbance in the balance of oxidation-reduction processes in the body that occurs due to the excessive production of free oxygen radicals that cellular homeostatic mechanisms are unable to neutralize. When the balance with the antioxidant system is disturbed, which happens when free oxygen radicals are in high concentrations, serious damage to biological molecules occurs, resulting in a series of pathophysiological and pathological changes, including cell death. Therefore, oxidative stress plays a significant role in the pathogenesis of many complications that can occur during pregnancy. The oxidative status of pregnant women is also influenced by socioeconomic living conditions, lifestyle habits, diet, smoking, and exposure to environmental air pollution. During a healthy pregnancy, the altered lipid profile and oxidative stress create an increased risk for premature birth and pregnancy-related diseases, and a predisposition to adult diseases.

The association of gut microbiome with recurrent pregnancy loss: A comprehensive review

The steady-state gut microbiome not only promotes the metabolism and absorption of nutrients that are difficult to digest by the host itself, but also participates in systemic metabolism. Once the dynamic balance is disturbed, the gut microbiome may lead to a variety of diseases. Recurrent pregnancy loss (RPL) affects 1-2% of women of reproductive age, and its prevalence has increased in recent years. According to the literature review, the gut microbiome is a new potential driver of the pathophysiology of recurrent abortion, and the gut microbiome has emerged as a new candidate for clinical prevention and treatment of RPL. However, few studies have concentrated on the direct correlation between RPL and the gut microbiome, and the mechanisms by which the gut microbiome influences recurrent miscarriage need further investigation. In this review, the effects of the gut microbiome on RPL were discussed and found to be associated with inflammatory response, the disruption of insulin signaling pathway and the formation of insulin resistance, maintenance of immunological tolerance at the maternal-fetal interface due to the interference with the immune imbalance of Treg/Th17 cells, and obesity.

Profiling of Immunomodulatory Genes and Quantification of CD25+ Cells in Different Types of Early Pregnancy Loss

INTRODUCTION

Maternal regulatory T (Treg) cells play a pivotal role in establishing general immune homeostasis in the decidua for maintenance of pregnancy. We aimed in this study to investigate the relationship between mRNA expression of immunomodulatory genes and CD25+ Treg cells with early pregnancy losses.

METHODS

Our study included 3 groups of early pregnancy losses including sporadic spontaneous abortions, recurrent spontaneous abortions, sporadic spontaneous abortions post IVF treatment and the control group. We performed RT-PCR for analyzing mRNA expression levels of 6 immunomodulatory genes and CD25 immunohistochemistry for quantification of Treg cells.

RESULTS

Only FOXP3, CD274 (PDL1), and TGFβ1 mRNA expression levels were significantly decreased in the miscarriage groups in comparison to the control group, whereas there was no significant mRNA expression change of CD4, IL2RA, and IL10. We also found significantly lower number of CD25+ cells in the miscarriages.

CONCLUSION

We conclude that decreased expression of FOXP3 and PD-L1 may play a significant role in the pathogenesis of spontaneous abortion cases whereas decreased expression of TGFβ1 gene may be associated with the occurrence of early loss in IVF-treated pregnancies. Additional immunoprofiling of Treg cell population is needed to quantify Treg cells in early pregnancy losses.

Research progress on the impact of anxiety and depression on embryo transfer outcomes of in vitro fertilization

Infertile women who receive in vitro fertilization-embryo transfer (IVF-ET) often present psychological distress such as anxiety, depression and perceived stress. This adverse psychological state can affect the immune homeostasis at the mother-fetus interface, the incubation of blastula and the receptivity of the maternal endometrium through the psycho-neuro-immuno-endocrine network, which in turns affect the proliferation, invasion and vascular remodeling of the embryo trophoblast, and reduces the success rate of embryo transfer. This adverse outcome of embryo transfer will further aggravate the psychological pain of patients, forming a vicious circle. The positive partner effect between husband and wife or the use of cognitive behavioral therapy, acupuncture, yoga and other measures for psychological intervention before and after IVF-ET, may break the vicious cycle and improve clinical pregnancy rate, continuous pregnancy rate and live birth rate after IVF-ET by alleviating anxiety and depression. This article reviews the research progress on anxiety and depression states in women receiving IVF-ET and the impact on outcome of IVF-ET and related mechanisms, as well as the application of psychological intervention for alleviating anxiety and depression, so as to provide insights in improving the outcome of IVF-ET.

Recurrent Abortion and the Involvement of Killer-Cell Immunoglobulin-like Receptor (KIR) Genes, Activated T Cells, NK Abnormalities, and Cytokine Profiles

Immune tolerance at the feto-maternal interface is crucial for the growth of the semi-allograft fetus in the womb. The outcome of pregnancy is dependent on a fine balance between various immunological forces. For a long time, the potential role of the immune system in pregnancy disorders has remained enigmatic. Current evidence has revealed that natural killer (NK) cells are the predominant immune cell population in the uterine decidua. NK cells cooperate with T-cells to provide an optimal microenvironment for the growth of the developing fetus by producing cytokines, chemokines, and angiogenic factors. These factors support trophoblast migration and angiogenesis which regulates the process of placentation. NK cells differentiate between "self" and "non-self" through their surface receptors known as killer-cell immunoglobulin-like receptors (KIRs). They induce immune tolerance through communication via their KIR and fetal human leucocyte antigens (HLA). KIRs are surface receptors of NKs that comprise both activating and inhibiting receptors. Due to the wide diversity manifested by its genes, the KIR repertoire is different in each individual. Significant evidence has implicated KIRs in recurrent spontaneous abortion (RSA); however, maternal KIR gene diversity in RSA is still unclear. Research has shown that immunological aberrancies including activating KIRs, NK abnormalities, and T cell downregulation are risk factors for RSA. In this review, we discuss relevant data from experimental studies on NK cell abnormalities, KIR, and T-cells in the incidence of recurrent spontaneous abortion.

Kisspeptin and kisspeptin receptor immunoreactivity in euploid and aneuploid choriodecidual tissues of recurrent pregnancy losses

OBJECTIVE

To study choriodecidual immunoreactivity of kisspeptin (KISS1) and its receptor (KISS1R) in recurrent pregnancy loss (RPL) due to aneuploidy (AnE) and unexplained (UE) RPL in comparison to control elective abortions (EAbs).

DESIGN

This is a case-control study.

SETTING

Tertiary care facility and affiliated research institute.

PATIENT(S)

Patients with either UE RPL (n = 10) or RPL due to AnE (n = 10) vs. a control group of patients who underwent EAb (n = 10).

INTERVENTION(S)

Immunohistochemistry of archived choriodecidual tissue samples.

MAIN OUTCOME MEASURE(S)

Histoscores of KISS1 and KISS1R immunoreactivity in the syncytiotrophoblast (SyT), cytotrophoblast (CyT), decidual glands (DeGs), and decidual stroma (DeS) across the 3 study groups.

RESULT(S)

There was no difference in both maternal and gestational ages among the 3 groups. Kisspeptin immunoreactivity was similar in the SyT, CyT, DeGs, and DeS of all groups. Similarly, KISS1R expression was not different in the DeGs or DeS among all study groups. In addition, there was no difference in KISS1R immunoreactivity in the SyTs and CyTs between patients with RPL due to AnE and those with UE RPL. However, KISS1R was significantly lower in the SyT and CyT of patients with RPL due to AnE and UE RPL than in those who underwent EAb.

CONCLUSION(S)

The expression of KISS1R is lower in the chorionic tissues of euploid (unexplained) and aneuploid RPLs than in the control group. The current results broaden our understanding of the role played by KISS1 and KISS1R in early placentation. Further investigation is necessary to determine whether KISS1 activity is the cause or a sequel of defective placentation.

Insights into the immunomodulatory regulation of matrix metalloproteinase at the maternal-fetal interface during early pregnancy and pregnancy-related diseases

Trophoblast immune cell interactions are central events in the immune microenvironment at the maternal-fetal interface. Their abnormalities are potential causes of various pregnancy complications, including pre-eclampsia and recurrent spontaneous abortion. Matrix metalloproteinase (MMP) is highly homologous, zinc(II)-containing metalloproteinase involved in altered uterine hemodynamics, closely associated with uterine vascular remodeling. However, the interactions between MMP and the immune microenvironment remain unclear. Here we discuss the key roles and potential interplay of MMP with the immune microenvironment in the embryo implantation process and pregnancy-related diseases, which may contribute to understanding the establishment and maintenance of normal pregnancy and providing new therapeutic strategies. Recent studies have shown that several tissue inhibitors of metalloproteinases (TIMPs) effectively prevent invasive vascular disease by modulating the activity of MMP. We summarize the main findings of these studies and suggest the possibility of TIMPs as emerging biomarkers and potential therapeutic targets for a range of complications induced by abnormalities in the immune microenvironment at the maternal-fetal interface. MMP and TIMPs are promising targets for developing new immunotherapies to treat pregnancy-related diseases caused by immune imbalance.

The Update Immune-Regulatory Role of Pro- and Anti-Inflammatory Cytokines in Recurrent Pregnancy Losses

Recurrent pregnancy losses (RPL) is a common reproductive disorder with various underlying etiologies. In recent years, rapid progress has been made in exploring the immunological mechanisms for RPL. A propensity toward Th2 over Th1 and regulatory T (Treg) over Th17 immune responses may be advantageous for reproductive success. In women with RPL and animals prone to abortion, an inordinate expression of cytokines associated with implantation and early embryo development is present in the endometrium or decidua secreted from immune and non-immune cells. Hence, an adverse cytokine milieu at the maternal-fetal interface assaults immunological tolerance, leading to fetal rejection. Similar to T cells, NK cells can be categorized based on the characteristics of cytokines they secrete. Decidual NK (dNK) cells of RPL patients exhibited an increased NK1/NK2 ratio (IFN-γ/IL-4 producing NK cell ratios), leading to pro-inflammatory cytokine milieu and increased NK cell cytotoxicity. Genetic polymorphism may be the underlying etiologies for Th1 and Th17 propensity since it alters cytokine production. In addition, various hormones participate in cytokine regulations, including progesterone and estrogen, controlling cytokine balance in favor of the Th2 type. Consequently, the intricate regulation of cytokines and hormones may prevent the RPL of immune etiologies. Local or systemic administration of cytokines or their antagonists might help maintain adequate cytokine milieu, favoring Th2 over Th1 response or Treg over Th17 immune response in women with RPL. Herein, we provided an updated comprehensive review regarding the immune-regulatory role of pro- and anti-inflammatory cytokines in RPL. Understanding the roles of cytokines involved in RPL might significantly advance the early diagnosis, monitoring, and treatment of RPL.

IL-6 and IL-8: An Overview of Their Roles in Healthy and Pathological Pregnancies

Interleukin-6 (IL-6) is an acknowledged inflammatory cytokine with a pleiotropic action, mediating innate and adaptive immunity and multiple physiological processes, including protective and regenerative ones. IL-8 is a pro-inflammatory CXC chemokine with a primary function in attracting and activating neutrophils, but also implicated in a variety of other cellular processes. These two ILs are abundantly expressed at the feto-maternal interface over the course of a pregnancy and have been shown to participate in numerous pregnancy-related events. In this review, we summarize the literature data regarding their role in healthy and pathological pregnancies. The general information related to IL-6 and IL-8 functions is followed by an overview of their overall expression in cycling endometrium and at the feto-maternal interface. Further, we provide an overview of their involvement in pregnancy establishment and parturition. Finally, the implication of IL-6 and IL-8 in pregnancy-associated pathological conditions, such as pregnancy loss, preeclampsia, gestational diabetes mellitus and infection/inflammation is discussed.

Immune Tolerance of Embryo Implantation and Pregnancy: The Role of Human Decidual Stromal Cell- and Embryonic-Derived Extracellular Vesicles

Embryo–endometrial communication plays a critical role in embryo implantation and the establishment of a successful pregnancy. Successful pregnancy outcomes involve maternal immune modulation during embryo implantation. The endometrium is usually primed and immunomodulated by steroid hormones and embryo signals for subsequent embryo implantation and the maintenance of pregnancy. The roles of extracellular vesicles (EVs) and microRNAs for the embryo–maternal interactions have been elucidated recently. New evidence shows that endometrial EVs and trophectoderm-originated EV cargo, including microRNAs, proteins, and lipids in the physiological microenvironment, regulate maternal immunomodulation for embryo implantation and subsequent pregnancy. On the other hand, trophoblast-derived EVs also control the cross-communication between the trophoblasts and immune cells. The exploration of EV functions and mechanisms in the processes of embryo implantation and pregnancy will shed light on a practical tool for the diagnostic or therapeutic approaches to reproductive medicine and infertility.

The effect of a traditional Chinese quadri-combination therapy and its component quercetin on recurrent spontaneous abortion: A clinical trial, network pharmacology and experiments-based study

Objective: To explore the effect and mechanisms of a traditional Chinese quadri-combination therapy [Bushen, Yiqi, Lixue and Yangtai (BYLY)] in treating recurrent spontaneous abortion (RSA). Methods: A clinical trial was conducted to study the effect of BYLY on RSA. Pharmacological network analysis and UPLC-Q/TOF-mass spectrometry (MS) were applied to investigate the key active component in BYLY and potential targets. Cellular experiments based on former results were performed to examine the mechanism of BYLY in the treatment of RSA. Results: Four hundred and eighty participants enrolled in the clinical trial. The results showed that, compared with the use of BYLY or duphaston alone, a combination of duphaston and BYLY could decrease the early abortion rate in RSA (p < 0.001). Network pharmacological analysis indicated that BYLY contained 132 active components and 146 core targets, and the quercetin maybe the key effective component. In vitro experiments found that pretreatment of quercetin at the correct concentration (2 μM) prevented hypoxia-induced viability and proliferation reduction, and apoptosis and mitochondrial dysfunction. Furthermore, quercetin could modulate mitochondrial fission/fusion balance in trophoblasts, and specifically decrease the expression of Drp1 by regulating miR-34a-5p. Conclusion: BYLY could improve pregnancy outcomes of RSA, based on multi-components and multi-targets. The protective effect of quercetin on trophoblasts, through decreasing Drp1 expression via regulating miR-34a-5p, might be one possible effective mechanism.

Effects of different doses of estrogen on ER expression and ovarian function in patients with unexplained recurrent abortion

Randomized trial. Objective: This study was designed to investigate the effects of different doses of estrogen on the expression of estrogen receptor (ER) in endometrial tissue and ovarian function in patients with unexplained recurrent spontaneous abortion (URSA). Methods: Eighty-eight patients with URSA in our outpatient department were randomly divided into three groups. They were treated with estradiol valerate (EV); standard dose of 4 mg/d (31 cases), high dose of 6 mg/d (27 cases) and 9 mg/d (30 cases). Progesterone was detected in the luteal phase, ovarian ovulation during follow-up treatment and the next month after drug withdrawal. ER expression in intima of EV 4 mg group, EV 6 mg group, and EV 9 mg group was detected by immunohistochemistry and PCR was performed before and 3 months after the treatment. Results: Anovulation of 88 URSA patients during hormone treatment was found as follows: 5 cases in the EV 4 mg group, 18 cases in the EV 6 mg group, 25 cases in the EV 9 mg group; Anovulation in the next month after drug withdrawal: 1 case in EV 4 mg group, 8 cases in EV 6 mg group, and 16 cases in EV 9 mg group. After stratified and grouped analysis, the expression of intimal ER in the EV 4 mg group, EV 6 mg, and EV 9 mg groups was significantly increased compared to before treatment in the 3 groups after treatment compared to before treatment (p < .05). There was no significant difference in ER expression between the three groups before and after treatment (p > .05). Conclusion: The higher the therapeutic dose of estrogen, the stronger the inhibition of ovarian ovulation, and the standard dose of estrogen has obvious advantages in increasing the expression of ER in intima. Limitation: 1) Insufficient sample size; 2) We need to increase the sampling time point to further observe the difference of estrogen in time effect, so as to obtain a more accurate action time of estrogen; 3) The longer-term effects of different doses of estrogen on intima were not studied, such as whether there are adverse pregnancy outcomes such as preterm birth, placental implantation, or premature exfoliation.

Human chorionic gonadotropin promotes murine Treg cells and restricts pregnancy-harmful proinflammatory Th17 responses

An equilibrium between proinflammatory and anti-inflammatory immune responses is essential for maternal tolerance of the fetus throughout gestation. To study the participation of fetal tissue-derived factors in this delicate immune balance, we analyzed the effects of human chorionic gonadotropin (hCG) on murine Treg cells and Th17 cells in vitro, and on pregnancy outcomes, fetal and placental growth, blood flow velocities and remodeling of the uterine vascular bed in vivo. Compared with untreated CD4⁺CD25⁺ T cells, hCG increased the frequency of Treg cells upon activation of the LH/CG receptor. hCG, with the involvement of IL-2, also interfered with induced differentiation of CD4⁺ T cells into proinflammatory Th17 cells. In already differentiated Th17 cells, hCG induced an anti-inflammatory profile. Transfer of proinflammatory Th17 cells into healthy pregnant mice promoted fetal rejection, impaired fetal growth and resulted in insufficient remodeling of uterine spiral arteries, and abnormal flow velocities. Our works show that proinflammatory Th17 cells have a negative influence on pregnancy that can be partly avoided by in vitro re-programming of proinflammatory Th17 cells with hCG.

Association of MTHFR 677C>T polymorphism with pregnancy outcomes in IVF/ICSI-ET recipients with adequate synthetic folic acid supplementation

Methylenetetrahydrofolate reductase (MTHFR) genetic polymorphism rs1801133 (677C>T) will decrease the utilization of folate. Folate deficiency and its resulting homocysteine (HCY) accumulation can impair female fertility. Folic acid (FA) supplementation is necessary in pregnant women who are undergoing in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) - embryo transfer (ET), and especially in women with MTHFR rs1801133 C-to-T mutations. At present, affordable and accessible synthetic FA is mainly used. However, some studies have suggested that 5-methylenetetrahydrofolate (5-MTHF), a type of active FA, may be more suitable for women with the MTHFR 677C>T polymorphism, since it is safer and more effective. This retrospective study aimed to evaluate whether the MTHFR rs1801133 gene polymorphism is related to the pregnancy outcomes of IVF/ICSI-ET recipients after sufficient supplementation with FA instead of 5-MTHF. Data on 692 women undergoing IVF/ICSI-ET and taking adequate FA were collected. Participant characteristics were compared using the Kruskal-Wallis test and Pearson chi-square test. Logistic regressions were used to calculate the odds ratio (OR) and 95% confidence interval (95% CI), after adjusting for age, BMI, method of fertilization, method of embryo transfer and number of embryos transferred. An additive model (T/T vs. C/C), dominant model (C/T + T/T vs. C/C), and recessive model (T/T vs. C/T + C/C) were evaluated. Analysis revealed that MTHFR rs1801133 in IVF/ICSI-ET women with adequate FA supplementation was not associated with the pregnancy rate but with age (OR = 0.91, 95% CI = 0.88, 0.94, P < 0.001) and BMI (OR = 0.95, 95% CI = 0.90, 0.997, P = 0.037). In 349 clinically pregnant women, no association of the MTHFR 677C>T with pregnancy outcomes was found in the additive model, dominant model, or recessive model. Of the 273 women with positive pregnancy outcomes, 34 had a preterm delivery. MTHFR 677C>T was not associated with a preterm delivery after adjusting for age and BMI. The current results indicated that MTHFR polymorphism rs1801133 was not related to the pregnancy rate or pregnancy outcomes of women undergoing IVF/ICSI-ET with adequate synthetic FA supplementation, suggesting that simple supplementation with less expensive and readily available FA, rather than expensive 5-MTHF, appeared to be appropriate.

Allogeneic lymphocytes immunotherapy in female infertility: Lessons learned and the road ahead

The endometrium is an essential tissue in the normal immunologic dialogue between the mother and the conceptus, which is necessary for the proper establishment and maintenance of a successful pregnancy. It's become evident that the maternal immune system plays a key role in the normal pregnancy's initiation, maintenance, and termination. In this perspective, the immune system contributes to regulating all stages of pregnancy, thus immunological dysregulation is thought to be one of the major etiologies of implantation failures. Many researchers believe that immune therapies are useful tactics for improving the live births rate in certain situations. Lymphocyte immunotherapy (LIT) is an active form of immunotherapy that, when used on the relevant subgroups of patients, has been shown in multiple trials to dramatically enhance maternal immunological balance and pregnancy outcome. The primary goal of LIT is to regulate the immune system in order to create a favorable tolerogenic immune milieu and tolerance for embryo implantation. However, there are a plethora of influential factors influencing its therapeutic benefits that merit to be addressed. The objective of our study is to discuss the mechanisms and challenges of allogeneic LIT.

A Potential Mechanism of Kidney-Tonifying Herbs Treating Unexplained Recurrent Spontaneous Abortion: Clinical Evidence From the Homogeneity of Embryo Implantation and Tumor Invasion

Background: Kidney-tonifying herbs (KTHs) are widely used to treat unexplained recurrent spontaneous abortion (URSA) based on the theory of traditional Chinese medicine (TCM). However, there is still a lack of systematic evaluation and mechanistic explanation for these treatments.

Objective: The purpose of this study was to assess the clinical efficacy, and to investigate the potential mechanisms, of KTH based on TCM for the treatment of URSA.

Methods: A systematic literature search was conducted within PubMed, Embase, China Biomedical Literature database, Web of Science (WOS), China National Knowledge Infrastructure (CNKI) database, and the Wanfang database to find articles reporting on the Chinese herbal formula based around KTH for treating URSA, which were published between January 2010 and June 2021. A full bibliometric analysis was carried out; in addition, randomized controlled trial (RCT) articles were selected for systematic evaluation and meta-analysis. The drugs with the highest frequency of KTHs were screened for meta-analysis. Finally, network analysis and molecular docking were used to study the key components and potential pathway of KTHs in the treatment of URSA.

Results: The meta-analysis included nine RCTs involving 1,054 subjects. Compared with the control groups, the clinical efficacy of TCM-based KTHs in the treatment of URSA patients significantly improved outcomes. Additionally, a component target pathway network was identified, which included 32 potential blood activating components and 113 main targets. Japonine, sopranol, lysine, and matrine were considered the most important bioactive molecules for KTHs. The key potential therapeutic pathway for URSA was a tumor-related signaling pathway. The target genes for URSA regulated by KTHs were highly similar to tumor biological processes such as the regulation of apoptotic signaling pathways, inflammatory responses, angiogenesis, and epithelial metabolic transition.

Conclusion: KTH has great potential for treating URSA. Because the maintenance of pregnancy has a high similarity with tumor invasion, the research relating to tumor mechanisms should also be followed up as it may lead to new ideas and breakthroughs for research into URSA. At the same time, embryonic and decidual cells share a high degree of cellular heterogeneity and spatial structural complexity with tumor cells, and a single cell combined with spatial omics may be the best future approach for validating KTH mechanisms.

Chromosomally normal miscarriage is associated with vaginal dysbiosis and local inflammation

BACKGROUND

Emerging evidence supports an association between vaginal microbiota composition and risk of miscarriage; however, the underlying mechanisms are poorly understood. We aim to investigate the vaginal microbial composition and the local immune response in chromosomally normal and abnormal miscarriages and compare this to uncomplicated pregnancies delivering at term.

METHODS

We used 16S rRNA gene based metataxonomics to interrogate the vaginal microbiota in a cohort of 167 women, 93 miscarriages (54 euploid and 39 aneuploid using molecular cytogenetics) and 74 women who delivered at term and correlate this with the aneuploidy status of the miscarriages. We also measured the concentrations of IL-2, IL-4, IL-6, IL-8, TNF-α, IFN-γ, IL-1β, IL-18 and IL-10 in cervical vaginal fluid.

RESULTS

We show that euploid miscarriage is associated with a significantly higher prevalence of Lactobacillus spp. deplete vaginal microbial communities compared to aneuploid miscarriage (P = 0.01). Integration of matched cervicovaginal fluid immune-profiles showed that Lactobacillus spp. depleted vaginal microbiota associated with pro-inflammatory cytokine levels most strongly in euploid miscarriage compared to viable term pregnancy (IL-1β; P < 0.001, IL-8; P = 0.01, IL-6; P < 0.001).

CONCLUSIONS

Our data suggest the vaginal microbiota plays an important aetiological role in euploid miscarriage and may represent a target to modify risk of pregnancy loss.

Progesterone: A Unique Hormone with Immunomodulatory Roles in Pregnancy

Progesterone is well known for its numerous endocrinologic roles in pregnancy but is also endowed with fascinating immunomodulatory capabilities. It can downregulate the induction of inflammatory reactions, the activation of immune cells and the production of cytokines, which are critical mediators of immune responses. These features appear to be critical to the success of pregnancy, given the ability of maternal immune reactivity to interfere with pregnancy and to contribute to several pregnancy complications. This review summarizes the contribution of maternal immune effectors in general, and cytokines in particular, to pregnancy complications such as recurrent miscarriage, pre-eclampsia and preterm labor; it describes the promise offered by supplementation with progesterone and the oral progestogen dydrogesterone, as well as the progesterone-induced blocking factor in the prevention and/or treatment of these serious complications.

Characterisation of peri-implantation endometrial Treg and identification of an altered phenotype in recurrent pregnancy loss

Recurrent Pregnancy Loss (RPL) affects 2-4% of couples, and with increasing numbers of pregnancy losses the risk of miscarrying a euploid pregnancy is increased, suggesting RPL is a pathology distinct from sporadic miscarriage that is due largely to lethal embryonic aneuploidy. There are a number of conditions associated with RPL including unspecified "immune" pathologies; one of the strongest candidates for dysregulation remains T regulatory cells as depletion in the very early stages of pregnancy in mice leads to pregnancy loss. Human endometrial Treg and conventional CD4T cells were isolated during the peri-implantation period of the menstrual cycle in normal women. We identified an endometrial Treg transcriptomic signature and validated an enhanced regulatory phenotype compared to peripheral blood Treg. Parous women had an altered endometrial Treg transcriptome compared to nulliparity, indicating acquired immune memory of pregnancy within the Treg population, by comparison endometrial conventional CD4T cells were not altered. We compared primary and secondary RPL to nulliparous or parous controls respectively. Both RPL subgroups displayed differentially expressed Treg gene transcriptomes compared to controls. We found increased cell surface S1PR1 and decreased TIGIT protein expression by Treg in primary RPL, confirming the presence of altered Treg in the peri-implantation RPL endometrium.

Clinical Impact of Nurses-Physicians Collaboration Intervention on the Treatment of Immune Recurrent Spontaneous Abortion with Low-Molecular-Weight Heparin

Anticoagulation is currently the preferred and effective treatment for patients with recurrent spontaneous abortion (RSA), but, due to the prevalence of mood disorders in RSA patients and the high number of adverse effects associated with long-term medication, effective care measures are often required. In this study, 94 patients with immune-type RSA who were admitted to our hospital from January 2018 to June 2019 were selected and randomly divided into a control group and a study group of 47 patients each; both groups received low-molecular-weight heparin treatment after admission, and the control group received conventional nursing interventions during treatment, while the patients in the study group received integrated medical and nursing care interventions. Pregnancy outcomes, pre- and postintervention scores on the Self-Assessment Scale (SAS), Self-Depression Scale (SDS), and Pittsburgh Sleep Quality Index (PSQI), levels of serum gamma-interferon (IFN-γ) and interleukin-4 (IL-4) and their ratios, complications, and patient satisfaction with the intervention were observed in both groups. The results showed that the success rate of fetal preservation in the study group (89.36%) was significantly higher than that in the control group (68.09%) (P < 0.05). After treatment, SAS, SDS, and PSQI scores decreased in both groups, with the study group being lower (P < 0.05). IFN-γ and IFN-γ/IL-4 levels decreased and IL-4 levels increased in both groups after treatment, with IFN-γ and IFN-γ/IL-4 being significantly lower and IL-4 levels being significantly higher in the study group than in the control group (P < 0.05). The incidence of adverse drug reactions in the study group was significantly lower than that in the control group (P < 0.05). Patients in the study group were more satisfied with all aspects of the intervention than the control group (P < 0.05). These results suggest that nurses-physicians collaboration intervention may improve the effectiveness of low-molecular-weight heparin therapy in patients with immune-type RSA. It helps to improve patient pregnancy outcomes, mood, sleep quality, and immune function and increases patient satisfaction.

Regulation of the innate immune cells during pregnancy: An immune checkpoint perspective

The foetus can be regarded as a half‐allograft implanted into the maternal body. In a successful pregnancy, the mother does not reject the foetus because of the immune tolerance mechanism at the maternal‐foetal interface. The innate immune cells are a large part of the decidual leukocytes contributing significantly to a successful pregnancy. Although the contributions have been recognized, their role in human pregnancy has not been completely elucidated. Additionally, the accumulated evidence demonstrates that the immune checkpoint molecules expressed on the immune cells are co‐inhibitory receptors regulating their activation and biological function. Therefore, it is critical to understand the immune microenvironment and explore the function of the innate immune cells during pregnancy. This review summarizes the classic immune checkpoints such as PD‐1, CTLA‐4 and some novel molecules recently identified, including TIM‐3, CD200, TIGIT and the Siglecs family on the decidual and peripheral innate immune cells during pregnancy. Furthermore, it emphasizes the role of the immune checkpoint molecules in pregnancy‐associated complications and reproductive immunotherapy.

Influence of Gestational Hormones on the Bacteria-Induced Cytokine Response in Periodontitis

Periodontitis is an inflammatory disease that affects the supporting structures of teeth. The presence of a bacterial biofilm initiates a destructive inflammatory process orchestrated by various inflammatory mediators, most notably proinflammatory cytokines, which are upregulated in the gingival crevicular fluid, leading to the formation of periodontal pockets. This represents a well-characterized microbial change during the transition from periodontal health to periodontitis; interestingly, the gestational condition increases the risk and severity of periodontal disease. Although the influence of periodontitis on pregnancy has been extensively reviewed, the relationship between pregnancy and the development/evolution of periodontitis has been little studied compared to the effect of periodontitis on adverse pregnancy outcomes. This review is aimed at summarizing the findings on the pregnancy-proinflammatory cytokine relationship and discussing its possible involvement in the development of periodontitis. We address (1) an overview of periodontal disease, (2) the immune response and possible involvement of proinflammatory cytokines in the development of periodontitis, (3) how bone tissue remodelling takes place with an emphasis on the involvement of the inflammatory response and metalloproteinases during periodontitis, and (4) the influence of hormonal profile during pregnancy on the development of periodontitis. Finally, we believe this review may be helpful for designing immunotherapies based on the stage of pregnancy to control the severity and pathology of periodontal disease.

DNA Methylation and Recurrent Pregnancy Loss: A Mysterious Compass?

Recurrent pregnancy loss (RPL) is a common and severe pathological pregnancy, whose pathogenesis is not fully understood. With the development of epigenetics, the study of DNA methylation, provides a new perspective on the pathogenesis and therapy of RPL. The abnormal DNA methylation of imprinted genes, placenta-specific genes, immune-related genes and sperm DNA may, directly or indirectly, affect embryo implantation, growth and development, leading to the occurrence of RPL. In addition, the unique immune tolerogenic microenvironment formed at the maternal-fetal interface has an irreplaceable effect on the maintenance of pregnancy. In view of these, changes in the cellular components of the maternal-fetal immune microenvironment and the regulation of DNA methylation have attracted a lot of research interest. This review summarizes the research progress of DNA methylation involved in the occurrence of RPL and the regulation of the maternal-fetal immune microenvironment. The review provides insights into the personalized diagnosis and treatment of RPL.

Analysis of Genomic Copy Number Variation in Miscarriages During Early and Middle Pregnancy

The purpose of this study was to explore the copy number variations (CNVs) associated with miscarriage during early and middle pregnancy and provide useful genetic guidance for pregnancy and prenatal diagnosis. A total of 505 fetal specimens were collected and CNV sequencing (CNV-seq) analysis was performed to determine the types and clinical significance of CNVs, and relevant medical records were collected. The chromosomal abnormality rate was 54.3% (274/505), among which the numerical chromosomal abnormality rate was 40.0% (202/505) and structural chromosomal abnormality rate was 14.3% (72/505). Chromosomal monosomy mainly occurred on sex chromosomes, and chromosomal trisomy mainly occurred on chromosomes 16, 22, 21, 15, 13, and 9. The incidence of numerical chromosomal abnormalities in ≥35 year-old age pregnant women was significantly higher than <35 year-old age group. The highest incidence of pathogenic CNV (pCNV) was found in fetuses at ≤6 weeks of pregnancy (5.26%), and the incidence of variants of unknown significance (VOUS) CNVs decreased gradually with the increase of gestational age. The rate of chromosomal abnormalities of fetuses in early pregnancy (59.5%) was higher than that of fetuses in middle pregnancy (27.2%) (p < 0.001). There were 168 genes in VOUS + pCNV regions. 41 functions and 12 pathways (p < 0.05) were enriched of these genes by Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Some meaningful genetic etiology information such as genes and pathways has been obtained, it may provide useful genetic guidance for pregnancy and prenatal diagnosis.

Role of Transforming Growth Factor-β1 in Regulating Fetal-Maternal Immune Tolerance in Normal and Pathological Pregnancy

Transforming growth factor-β (TGF-β) is composed of three isoforms, TGF-β1, TGF-β2, and TGF-β3. TGF-β1 is a cytokine with multiple biological functions that has been studied extensively. It plays an important role in regulating the differentiation of immune cells and maintaining immune cell functions and immune homeostasis. Pregnancy is a carefully regulated process. Controlled invasion of trophoblasts, precise coordination of immune cells and cytokines, and crosstalk between trophoblasts and immune cells play vital roles in the establishment and maintenance of normal pregnancy. In this systematic review, we summarize the role of TGF-β1 in regulating fetal-maternal immune tolerance in healthy and pathological pregnancies. During healthy pregnancy, TGF-β1 induces the production of regulatory T cells (Tregs), maintains the immunosuppressive function of Tregs, mediates the balance of M1/M2 macrophages, and regulates the function of NK cells, thus participating in maintaining fetal-maternal immune tolerance. In addition, some studies have shown that TGF-β1 is dysregulated in patients with recurrent spontaneous abortion or preeclampsia. TGF-β1 may play a role in the occurrence and development of these diseases and may be a potential target for the treatment of these diseases.

Altered eutopic endometrial T-regulatory and T-helper 17 lymphocyte ratio in women with unexplained subfertility

PROBLEM

Perturbations in T-helper lymphocyte profiles have previously been associated with endometriosis related subfertility and conception failure. Hence a retrospective in vitro study was conducted to evaluate the relationship between T-regulatory (Treg) and T-helper 17 (Th17) lymphocytes in the eutopic endometrium of women with unexplained subfertility and correlate these profiles to their conception status.

METHOD OF STUDY

Eutopic endometrial biopsies were collected during the mid-secretory phase of the menstrual cycle, from women with unexplained subfertility. These samples were evaluated immunohistochemically for Treg and Th17 lymphocytes as well as the related proinflammatory cytokine, Interleukin-17 (IL-17). These eutopic endometrial T lymphocyte subpopulations were compared to the patients' conception status in subsequent cycles.

RESULTS

Though Treg cells were not indicative of conception success in subsequent cycles, patients who maintained their subfertile (no conception) status were observed to have a higher Th17 cell count in their eutopic endometrium. The ratio of Treg:Th17 cell counts was significantly correlated to patient conception status as well. These trends stayed consistent irrespective of concurrent endometriosis.

CONCLUSION

Patients with a high proinflammatory Th17 lymphocyte profile and low Treg:Th17 ratio in their eutopic endometrium during the secretory phase of their menstrual cycle are more likely to not conceive in subsequent cycles.

Cytokines, Hormones and Cellular Regulatory Mechanisms Favoring Successful Reproduction

Its semi-allogeneic nature renders the conceptus vulnerable to attack by the maternal immune system. Several protective mechanisms operate during gestation to correct the harmful effects of anti-fetal immunity and to support a healthy pregnancy outcome. Pregnancy is characterized by gross alterations in endocrine functions. Progesterone is indispensable for pregnancy and humans, and it affects immune functions both directly and via mediators. The progesterone-induced mediator - PIBF - acts in favor of Th2-type immunity, by increasing Th2 type cytokines production. Except for implantation and parturition, pregnancy is characterized by a Th2-dominant cytokine pattern. Progesterone and the orally-administered progestogen dydrogesterone upregulate the production of Th2-type cytokines and suppress the production of Th1 and Th17 cytokine production in vitro. This is particularly relevant to the fact that the Th1-type cytokines TNF-α and IFN-γ and the Th17 cytokine IL-17 have embryotoxic and anti-trophoblast activities. These cytokine-modulating effects and the PIBF-inducing capabilities of dydrogesterone may contribute to the demonstrated beneficial effects of dydrogesterone in recurrent spontaneous miscarriage and threatened miscarriage. IL-17 and IL-22 produced by T helper cells are involved in allograft rejection, and therefore could account for the rejection of paternal HLA-C-expressing trophoblast. Th17 cells (producing IL-17 and IL-22) and Th22 cells (producing IL-22) exhibit plasticity and could produce IL-22 and IL-17 in association with Th2-type cytokines or with Th1-type cytokines. IL-17 and IL-22 producing Th cells are not harmful for the conceptus, if they also produce IL-4. Another important protective mechanism is connected with the expansion and action of regulatory T cells, which play a major role in the induction of tolerance both in pregnant women and in tumour-bearing patients. Clonally-expanded Treg cells increase at the feto-maternal interface and in tumour-infiltrating regions. While in cancer patients, clonally-expanded Treg cells are present in peripheral blood, they are scarce in pregnancy blood, suggesting that fetal antigen-specific tolerance is restricted to the foeto-maternal interface. The significance of Treg cells in maintaining a normal materno-foetal interaction is underlined by the fact that miscarriage is characterized by a decreased number of total effector Treg cells, and the number of clonally-expanded effector Treg cells is markedly reduced in preeclampsia. In this review we present an overview of the above mechanisms, attempt to show how they are connected, how they operate during normal gestation and how their failure might lead to pregnancy pathologies.

Clinical consequences of defective decidualization

Decidualization is characterized by a series of genetic, metabolic, morphological, biochemical, vascular and immune changes occurring in the endometrial stroma in response to the implanting embryo or even before conception and involves the stromal cells of the endometrium. It is a fundamental reproductive event occurring in mammalian species with hemochorial placentation. A growing body of experimental and clinical evidence strongly suggests that defective or disrupted decidualization contributes to the establishment of an inappropriate maternal-fetal interface. This has relevant clinical consequences, ranging from recurrent implantation failure and recurrent pregnancy loss in early pregnancy to several significant complications of advanced gestation. Moreover, recent evidence indicates that selected diseases of the endometrium, such as chronic endometritis and endometriosis, can have a detrimental impact on the decidualization response in the endometrium and may help explain some aspects of the reduced reproductive outcome associated with these conditions. Further research efforts are needed to fully understand the biomolecular mechanisms ans events underlying an abnormal decidualization response. This will permit the development of new diagnostic and therapeutic strategies aimed to improve the likelihood of achieveing a successful pregnancy.

The decidual expression of Interleukin-7 is upregulated in early pregnancy loss

BACKGROUND

Maternal immunological rejection of the semi-allogenic fetus is discussed as one of the significant factors involved in early pregnancy loss. An array of cytokines secreted by both maternal and fetal cells is involved in generating a delicate maternal immune tolerance. Interleukin-7 (IL-7) is discussed to play a key role in pro-inflammatory processes, but there is still limited insight into the pathophysiological input on placentation and embryonic development in early pregnancy loss.

PATIENTS AND METHODS

Cytokine level differences were identified with quantitative real-time PCR in placental tissue from spontaneous abortions (SA) (n = 18), recurrent spontaneous abortions (RSA) (n = 15), and healthy pregnancies (n = 15) at gestational weeks 7 to 14. Protein expression of IL-7 in the decidua was investigated by immunohistochemistry. IL-7-expressing cells were identified with double-immunofluorescence.

RESULTS

Decidua of women with RSA expressed almost 51-times higher values of IL-7 in gene expression analysis. Immunohistochemistry identified a significant upregulation of IL-7 in the decidua of RSA specimens (p = .013) and in the decidua of women with SA (p = .004). Double-immunofluorescence confirmed decidual stroma cells as IL-7-expressing cells.

CONCLUSION

Significantly elevated IL-7 values in the decidua of spontaneous and recurrent miscarriages imply a crucial role of the cytokine in the signaling at the feto-maternal interface of the placenta. An overexpression of IL-7 could result in early pregnancy loss by inducing a pro-inflammatory environment. Proven to be valuable in other autoimmune diseases, targeting IL-7 signaling therapeutically may prove to be a very beneficial treatment option for RSA patients.

Systemic Characterization of Novel Immune Cell Phenotypes in Recurrent Pregnancy Loss

Recurrent pregnancy loss (RPL) is a disturbing disease in women, and 50% of RPL is reported to be associated with immune dysfunction. Most previous studies of RPL focused mainly on the relationship between RPL and either T cells or natural killer (NK) cells in peripheral blood and the decidua; few studies presented the systemic profiles of the peripheral immune cell subsets in RPL women. Herein, we simultaneously detected 63 immune cell phenotypes in the peripheral blood from nonpregnant women (NPW), women with a history of normal pregnancy (NP) and women with a history of RPL (RPL) by multi-parameter flow cytometry. The results demonstrated that the percentages of naïve CD4⁺ T cells, central memory CD4⁺ T cells, naïve CD8⁺ T cells, mature NK cells, Vδ1⁺ T cells and the ratio of Vδ1⁺ T cells/Vδ2⁺ T cells were significantly higher in the RPL group than those in the NPW and NP groups, whereas the percentages of terminal differentiated CD4⁺ T cells, effective memory CD4⁺ T cells, immature NK cells and Vδ2⁺ T cells were significantly lower in the RPL group than those in the NPW and NP groups. Interestingly, we found that peripheral T helper (T_PH) cells were more abundant in the NPW group than in the NP and RPL groups. In addition, we also determined the 5^th percentile lower limit and 95^th percentile upper limit of the significantly changed immunological parameters based on the files of the NPW group. Taken together, this is the first study to simultaneously characterize the multiple immune cell subsets in the peripheral blood at a relatively large scale in RPL, which might provide a global readout of the immune status for clinicians to identify clinically-relevant immune disorders and guide them to make clear and individualized advice and treatment plans.

Evaluation of paternal lymphocyte immunotherapy and potential biomarker mixed lymphocyte reaction-blocking factor in an Argentinian cohort of women with unexplained recurrent spontaneous abortion and unexplained infertility

PROBLEM

Analyze the effect of paternal immunotherapy treatment (PIT) in primary and secondary unexplained recurrent spontaneous abortion (URSA) and unexplained infertility (UI).

METHODS OF STUDY

A retrospective study analyzed a two-year follow-up between the generation of MLR-Bfs after PIT treatment (or controls first consultation) and a live birth. Recruited patients included primary URSA with two or more miscarriages at <12 weeks gestation, secondary URSA with previous live birth before two or more miscarriages, and UI with inability to conceive after 2 years of regular unprotected intercourse or in vitro fertilizations (IVF). PIT treated were compared with untreated controls.

RESULTS

Primary URSA: live birth was 241/416 (58%) versus 64/282 (23%) controls (p < .0001). Up to age 35, success was 158/217 (73%) and 37/144 (26%) controls (p < .0001). With 3 or more previous URSA, success was 90/135 (67%) versus 17/79 (22%) controls (p < .0001). Between ages 36 and 40, success was 69/147(47%) versus 22/98 (22%) controls (p < .0003), with 3 or more previous URSA live birth was 45/95 (47%) versus 6/46 (13%) controls (p < .0001). In UI, live birth was 99/298 (33%) versus 54/263 (21%) in controls (p < .0009) that increased under age 35 to 53/116 (46%) in treated versus 26/101 (26%) controls (p < .0056). In PIT treated, IVF success required a median of 1 (1.37 ± 0.67) versus a median of 3 IVF procedures (2.75 ± 0.84) in controls.

CONCLUSION

PIT is a successful treatment for primary and secondary URSA, and UI. PIT reduced the number of IVF required for achieving pregnancy.

Alterations of Circulating Biomarkers During Late Term Pregnancy Complications in the Horse Part I: Cytokines

Equine abortions are attributed to both infectious and noninfectious causes. Clinical extrapolations are often made from the experimental model for ascending placentitis towards other causes of fetal compromise, including various markers of inflammation, including the cytokines IL-2, 5, IL-6, IL-10, IFNγ, and TNF. It is unknown if these cytokine changes are noted under field conditions, or if they increase preceding other pregnancy related complications. To assess this, Thoroughbred mares (n = 702) had weekly blood obtained beginning in December 2013 and continuing until parturition. Fetal membranes were submitted to the UKVDL for complete gross and pathologic assessment and classified as either ascending placentitis (n = 6), focal mucoid placentitis (n = 6), idiopathic abortion (n = 6) or control (n = 20). Weekly serum samples were analyzed via immunoassay for concentrations of IL-2, IL-5, IL-6, IL-10, IFNγ, and TNF. For both focal mucoid placentitis and ascending placentitis, an increase (P < .05) in the concentrations of IL-2, IL-5, IL-6, IL-10, IFNγ, and TNF was noted preceding parturition in comparison to controls. Cytokine profiles preceding idiopathic abortion did not differ from controls. In conclusion, serum cytokines may be considered potential biomarkers for the prediction of placental infection, while no changes in cytokine profiles were noted when noninfectious causes of abortion occurred. Additionally, this is the first study to report an increase in cytokines during the disease process of focal mucoid placentitis, the etiology of which includes Nocardioform placentitis.

Regulatory effect of daphnetin on the balance of Th17 and Treg cells in the peripheral blood mononuclear cells from patients with unexplained recurrent pregnancy loss

Introduction

There has a close relationship between the balance of T helper 17 (Th17) cells and Foxp3+ regulatory T cells (Treg) and unexplained recurrent pregnancy loss (URPL). The present study is to investigate the regulatory effect of daphnetin, which is extracted from Daphne odora Var, on the balance of Th17 and Treg cells in the peripheral blood mononuclear cells (PBMCs) from patients with URPL.

Material and methods

PBMCs were isolated from 35 pregnant women with URPL and 35 women with normal early pregnancies, respectively and treated with daphnetin for three days. Flow cytometry was performed to measure the proportions of Th17 and Treg cells. The level of expression of IL-6, TGF-β1 and IL-2 were detected using enzyme-linked immunosorbent assay (ELISA) and the level of expression of FoxP3, RORγt, signal transducers and activators of transcriotion 3 (STAT3) and STAT5 were detected by RT-PCR.

Results

The concentrations of Th17-type cytokines IL-2 were significantly decreased in the URPL group after treatment (p < 0.01). Treg-type cytokines such as TGF-β1 and IL-6 were significantly increased after treatment (p < 0.01). At the same time, daphnetin may induce a decrease in the ratio of RORγt to Foxp3 and a Treg cell bias, which would be beneficial for pregnancy maintenance. Futhermore the expression level of STAT3 were higher in the URPL patients whereas STAT5 were lower than those in the control subjects.

Conclusions

In conclusion, daphnetin may have regulatory effect on the balance of Th17 and Treg cells in the peripheral blood mononuclear cells from patients with URPL.