Cytokine expression by first-trimester human chorionic villi

Neurodevelopmental Disruptions in Children of Preeclamptic Mothers: Pathophysiological Mechanisms and Consequences

Preeclampsia (PE) is a multisystem disorder characterized by elevated blood pressure in the mother, typically occurring after 20 weeks of gestation and posing risks to both maternal and fetal health. PE causes placental changes that can affect the fetus, particularly neurodevelopment. Its key pathophysiological mechanisms encompass hypoxia, vascular and angiogenic dysregulation, inflammation, neuronal and glial alterations, and disruptions in neuronal signaling. Animal models indicate that PE is correlated with neurodevelopmental alterations and cognitive dysfunctions in offspring and in humans, an association between PE and conditions such as cerebral palsy, autism spectrum disorder, attention deficit hyperactivity disorder, and sexual dimorphism has been observed. Considering the relevance for mothers and children, we conducted a narrative literature review to describe the relationships between the pathophysiological mechanisms behind neurodevelopmental alterations in the offspring of PE mothers, along with their potential consequences. Furthermore, we emphasize aspects pertinent to the prevention/treatment of PE in pregnant mothers and alterations observed in their offspring. The present narrative review offers a current, complete, and exhaustive analysis of (i) the pathophysiological mechanisms that can affect neurodevelopment in the children of PE mothers, (ii) the relationship between PE and neurological alterations in offspring, and (iii) the prevention/treatment of PE.

Gene crosstalk between COVID-19 and preeclampsia revealed by blood transcriptome analysis

Background

The extensive spread of coronavirus disease 2019 (COVID-19) has led to a rapid increase in global mortality. Preeclampsia is a commonly observed pregnancy ailment characterized by high maternal morbidity and mortality rates, in addition to the restriction of fetal growth within the uterine environment. Pregnant individuals afflicted with vascular disorders, including preeclampsia, exhibit an increased susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection via mechanisms that have not been fully delineated. Additionally, the intricate molecular mechanisms underlying preeclampsia and COVID-19 have not been fully elucidated. This study aimed to discern commonalities in gene expression, regulators, and pathways shared between COVID-19 and preeclampsia. The objective was to uncover potential insights that could contribute to novel treatment strategies for both COVID-19 and preeclampsia.

Method

Transcriptomic datasets for COVID-19 peripheral blood (GSE152418) and preeclampsia blood (GSE48424) were initially sourced from the Gene Expression Omnibus (GEO) database. Subsequent to that, we conducted a subanalysis by selecting females from the GSE152418 dataset and employed the "Deseq2" package to identify genes that exhibited differential expression. Simultaneously, the "limma" package was applied to identify differentially expressed genes (DEGs) in the preeclampsia dataset (GSE48424). Following that, an intersection analysis was conducted to identify the common DEGs obtained from both the COVID-19 and preeclampsia datasets. The identified shared DEGs were subsequently utilized for functional enrichment analysis, transcription factor (TF) and microRNAs (miRNA) prediction, pathway analysis, and identification of potential candidate drugs. Finally, to validate the bioinformatics findings, we collected peripheral blood mononuclear cell (PBMC) samples from healthy individuals, COVID-19 patients, and Preeclampsia patients. The abundance of the top 10 Hub genes in both diseases was assessed using real-time quantitative polymerase chain reaction (RT-qPCR).

Result

A total of 355 overlapping DEGs were identified in both preeclampsia and COVID-19 datasets. Subsequent ontological analysis, encompassing Gene Ontology (GO) functional assessment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, revealed a significant association between the two conditions. Protein-protein interactions (PPIs) were constructed using the STRING database. Additionally, the top 10 hub genes (MRPL11, MRPS12, UQCRH, ATP5I, UQCRQ, ATP5D, COX6B1, ATP5O, ATP5H, NDUFA6) were selected based on their ranking scores using the degree algorithm, which considered the shared DEGs. Moreover, transcription factor-gene interactions, protein-drug interactions, co-regulatory networks of DEGs and miRNAs, and protein-drug interactions involving the shared DEGs were also identified in the datasets. Finally, RT-PCR results confirmed that 10 hub genes do exhibit distinct expression profiles in the two diseases.

Conclusion

This study successfully identified overlapping DEGs, functional pathways, and regulatory elements between COVID-19 and preeclampsia. The findings provide valuable insights into the shared molecular mechanisms and potential therapeutic targets for both diseases. The validation through RT-qPCR further supports the distinct expression profiles of the identified hub genes in COVID-19 and preeclampsia, emphasizing their potential roles as biomarkers or therapeutic targets in these conditions.

Echinochrome A Reverses Kidney Abnormality and Reduces Blood Pressure in a Rat Model of Preeclampsia

We aimed to observe the effects of Echinochrome A (Ech A) on systemic changes using a rat model of preeclampsia. The results showed that an infusion of angiotensin II (Ang II) through an osmotic pump (1 μg/kg/min) on GD 8 increased systolic and diastolic blood pressures and reduced fetal weight and placental weight. The diameters of the glomeruli were expended and glomeruli capillaries were diminished. No change was observed in the heart and liver in the Ang II group, but epithelial structures were disrupted in the uterus. Ech A treatment on GD 14 (100 μg/μL) through the jugular vein reduced systolic and diastolic blood pressures and reversed glomerulus alterations, but the fetal or placental parameters were unaffected. Ech A only partly reversed the effect on the uterus. The mRNA expression of TNF-α was increased and IL-10 and VEGF were reduced in the uterus of the Ang II group, while Ech A restored these changes. A similar trend was observed in the kidney, liver, and heart of this group. Furthermore, Bcl-2 was reduced and Bcl-2/Bax ratios were significantly reduced in the kidney and heart of the Ang II group, while Ech A reversed these changes. We suggest that Ech A modulates inflammation and apoptosis in key systemic organs in Ang II-induced rat preeclampsia and preserves kidney and uterus structures and reduces blood pressure.

Gene model-related m6A expression levels predict the risk of preeclampsia

Background

This is the first study to explore the potential functions and expression patterns of RNA N6-methyladenosine (m6A) and potential related genes in preeclampsia.

Methods

We identified two m6A modification patterns through unsupervised cluster analysis and validated them by principal component analysis. We quantified the relative abundance of specific infiltrating immunocytes using single-sample gene set enrichment analysis (ssGSEA) and the Wilcoxon test. To screen hub genes related to m6A regulators, we performed weighted gene coexpression network analysis. Functional enrichment analysis was conducted for differential signalling pathways and cellular processes. Preeclampsia patients were grouped by consensus clustering based on differentially expressed hub genes and the relationship between different gene-mediated classifications and clinical features.

Results

Two m6A clusters in preeclampsia, cluster A and cluster B, were determined based on the expression of 17 m6A modification regulators; ssGSEA revealed seven significantly different immune cell subtypes between the two clusters. A total of 1393 DEGs and nine potential m6A-modified hub genes were screened. We divided the patients into two groups based on the expression of these nine genes. We found that almost all the patients in m6A cluster A were classified into hub gene cluster 1 and that a lower gestational age may be associated with more m6A-associated events.

Conclusions

This study revealed that hub gene-mediated classification is consistent with m6A modification clusters for predicting the clinical characteristics of patients with preeclampsia. Our results provide new insights into the molecular mechanisms of preeclampsia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01254-4.

The impact of COVID-19 on pregnancy and therapeutic drug development

Emerging data show that pregnant women with COVID-19 are at significantly higher risk of severe outcomes compared with non-pregnant women of similar age. This review discusses the invaluable insight revealed from vaccine clinical trials in women who were vaccinated and inadvertently became pregnant during the trial period. It further explores a number of clinical avenues in their management and proposes a drug development strategy in line with clinical trials for vaccines and drug treatments for the drug development community. Little is known of the long-term effects of COVID-19 on the mother and the baby. Our hypothesis that COVID-19 predisposes pregnant women to pre-eclampsia or hypertensive disorders during pregnancy is supported by a clinical study, and this may also adversely impact a woman's cardiovascular disease risk later in life. It may also increase a woman's risk of pre-eclampsia in subsequent pregnancy. This is an ever-evolving landscape, and early knowledge for healthcare providers and drug innovators is offered to ensure benefits outweigh the risks. COVID-19 mRNA vaccines appear to generate robust humoral immunity in pregnant and lactating women. This novel approach to vaccination also offers new ways to therapeutically tackle disorders of many unmet medical needs. LINKED ARTICLES: This article is part of a themed issue on The second wave: are we any closer to efficacious pharmacotherapy for COVID 19? (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.10/issuetoc.

Placental Expression and Relative Role of Anti-inflammatory Annexin A1 and Animal Lectin Galectin-3 in the Pathogenesis of Preeclampsia

Preeclampsia (PE) remains the major cause for maternal and foetal mortality and morbidity all over the world. Preeclampsia is associated with maternal, placental aggravated inflammatory response and generalized endothelial damage. AnnexinA1 (AnxA1) is glucocorticoid regulated protein regulates a wide range of cellular and molecular steps of the inflammatory response and is implicated in resolution of inflammation. Galectin-3 (Gal-3), β-galcotoside-binding lectin participates in many functions, both intra- and extracellularly. Recently it has been shown that galectin-3 modulates the inflammation. Role of AnxA1 and Galectin-3 is poorly studied in context with human reproductive disease like Preeclampsia. Therefore, the present study examined the expression of AnxA1 and Gal-3 which are involved in modulation of inflammation and their association in the placental bed of pregnancy with and without PE. The study group consisted of placental bed biopsy tissues obtained from pregnancies with PE (n = 30) and without (n = 30) PE. The expression of AnxA1 and Gal-3 in the placental bed tissues was evaluated quantitatively using Immunohisto-chemistry (IHC), western blot and mRNA expression analysis by quantitative RT-PCR. Our IHC, western blot and RT PCR analyses showed the increase in the expression of AnxA1 and Gal-3 in PE group compared with the normotensive control group (P < 0.001). The increased expression of AnxA1 and Gal-3 in placental bed may be associated with a systemic inflammatory response in PE, suggesting role of AnxA1 and Gal-3 in PE pathogenesis.

Abnormal development of cerebral arteries and veins in offspring of experimentally preeclamptic rats: Potential role in perinatal stroke

Preeclampsia, a hypertensive disorder of pregnancy, complicates up to 10 % of all pregnancies and increases the risk for perinatal stroke in offspring. The mechanism of this increase is unknown, but may involve vascular dysfunction. The goal of this study was to evaluate the effect of experimental preeclampsia (ePE) on cerebrovascular function in offspring to eludciate a possible mechanism for this association. Dams were fed a high cholesterol diet beginning on day 7 of gestation to induce experimental preeclampsia. Middle cerebral arteries (MCA) and the Vein of Galen (VoG) were isolated from pups from ePE dams and compared to pups from normal pregnant (NP) dams at postnatal days 16, 23, and 30 and studied pressurized in an arteriograph chamber. Markers of inflammation and oxidative stress were measured in serum. Our results suggest altered structure and function in both MCA and VoG of ePE pups. We also found evidence of systemic inflammation and oxidative stress in ePE pups. These findings provide a potential link between preeclampsia and the occurrence or severity of perinatal stroke.

The Role of Inflammation in the Pathogenesis of Preeclampsia

Preeclampsia (PE) affects 5-8% of pregnant women, and it is the major cause of perinatal morbidity and mortality. It is defined as arterial hypertension in women after 20 weeks of gestation which cooccurs with proteinuria (300 mg/d) or as arterial hypertension which is accompanied by one of the following: renal failure, liver dysfunction, hematological or neurological abnormalities, intrauterine growth restriction, or uteroplacental insufficiency. Currently, pathophysiology of preeclampsia poses a considerable challenge for perinatology. Preeclampsia is characterized by excessive and progressive activation of the immune system along with an increase in proinflammatory cytokines and antiangiogenic factors in fetoplacental unit as well as in vascular endothelium in pregnant women. A single, major underlying mechanism of preeclampsia is yet to be identified. This paper discusses the current understanding of the mechanisms which underlie the development of the condition. Some significant factors responsible for PE development include oxidative stress, abnormal concentration and activity in mononuclear phagocytic system, altered levels of angiogenic and antiangiogenic factors, and impaired inflammatory response triggered by inflammasomes. Detailed understanding of pathophysiology of inflammatory process in PE can largely contribute to new, targeted anti-inflammatory therapies that may improve perinatal outcomes in PE patients.

Changing the paradigm of IFN-γ at the interface between innate and adaptive immunity: Macrophage-derived IFN-γ

IFN-γ plays a critical role in the immune response to bacterial infections. It is established that IFN-γ is mainly produced by NK/ILC1 cells and T cells, and most of papers have rejected the biologic reality of alternative sources for more than 20 years. Here, we are proposing to revisit this dogma and discuss the role of macrophage-derived IFN-γ in bacterial infections. Our hypothesis is based on a panel of publications and is recently revived by our results on placenta, a chimeric organ in which the immune response is tailored to protect the fetus from mother's immune response. The culture of purified placental macrophages is associated with a production of IFN-γ that may contribute to fetal protection from bacterial infections before eliciting a Th1-like immune response potentially pathogenic for pregnancy. Hence, macrophage IFN-γ may be a novel actor of early crosstalk between innate and adaptive immunity in the context of host defense against bacterial infections.

The role of serum interleukin-37 levels, inflammation and blood pressure in patients with preeclampsia

AIM

Preeclampsia is one of the major causes of perinatal, fetal, and maternal mortality and morbidity. The aim of this study was to investigate the association of serum interleukin 37 (IL 37) with preeclampsia.

METHODS

39 women with preeclampsia were included as the study group. 38 healthy, and normotensive pregnant women, at similar gestational week with similar gravidity volunteered as the control group. Clinical findings, biochemical parameters, maternal and perinatal outcomes, and the serum concentrations of IL37 were compared between the groups. The relationship of IL 37 concentrations with clinical findings and blood pressure outcomes were also investigated.

RESULTS

Maternal serum IL 37 concentrations were significantly higher in patients with preeclampsia compared to the healthy pregnant women in the control group (p = .005). IL 37 positively correlated systolic blood pressure (BP) (r = 0.344, p = .002), and diastolic BP (r = 0.332, p = .003). IL 37 was identified as an independent predictor of preeclampsia.

CONCLUSIONS

Serum IL 37 concentrations were higher in preeclamptic patients compared to healthy pregnant women. Furthermore, IL 37 concentrations achieved success in identifying preeclampsia with hypertension. Increased IL 37 activity may have a role in the pathophysiology of preeclampsia.

Preeclampsia: From Inflammation to Immunoregulation

Preeclampsia (PE) affects 5% to 7% of pregnant women each year worldwide, accounts for up to 18% of maternal deaths in the United States each year, and is the number 1 cause of premature births. Preeclampsia is associated with hypertension after the 20th week of gestation with or without proteinuria, in conjunction with fetal growth restriction, maternal endothelial dysfunction, and chronic immune activation. The mechanisms leading to the development of PE are unclear. However, it is thought that shallow trophoblast invasion and insufficient remodeling of uterine spiral arteries result in placental ischemia. Consequently, an immune imbalance characterized by increases in proinflammatory CD4⁺ T cells and cytokines along with decreases in regulatory T cells and anti-inflammatory cytokines occurs. This imbalance leads to chronic inflammation and ensuing oxidative stress, proinflammatory cytokines, and autoantibodies. Studies performed in our laboratories, using the Reduced Uterine Perfusion Pressure (RUPP) rat model of placental ischemia, have demonstrated a role for this immune imbalance to mediate PE pathophysiology and identified potential mechanisms of immunoregulation that may be of benefit in the treatment of PE. Therefore, the purpose of this commentary is to review studies demonstrating the positive effects of immunoregulatory factors in the RUPP rat model of PE. Restoration of the immune balance in PE may be a potential strategy for the development of therapeutic interventions that could improve maternal and fetal outcomes associated with this maternal syndrome.

Identifying immune mechanisms mediating the hypertension during preeclampsia

Preeclampsia (PE) is a pregnancy-associated disorder that affects 5-8% of pregnancies and is a major cause of maternal, fetal, and neonatal morbidity and mortality. Hallmark characteristics of PE are new onset hypertension after 20 wk gestation with or without proteinuria, chronic immune activation, fetal growth restriction, and maternal endothelial dysfunction. However, the pathophysiological mechanisms that lead to the development of PE are poorly understood. Recent data from studies of both clinical and animal models demonstrate an imbalance in the subpopulations of CD4+ T cells and a role for these cells as mediators of inflammation and hypertension during pregnancy. Specifically, it has been proposed that the imbalance between two CD4+ T cell subtypes, regulatory T cells (Tregs) and T-helper 17 cells (Th17s), is involved in the pathophysiology of PE. Studies from our laboratory highlighting how this imbalance contributes to vasoactive factors, endothelial dysfunction, and hypertension during pregnancy will be discussed in this review. Therefore, the purpose of this review is to highlight hypertensive mechanisms stimulated by inflammatory factors in response to placental ischemia, thereby elucidating a role.

The role of inflammation in the pathology of preeclampsia

Preeclampsia (PE) affects 5-7% of all pregnancies in the United States and is the leading cause of maternal and prenatal morbidity. PE is associated with hypertension after week 20 of gestation, decreased renal function and small-for-gestational-age babies. Women with PE exhibit chronic inflammation and production of autoantibodies. It is hypothesized that during PE, placental ischaemia occurs as a result of shallow trophoblast invasion which is associated with an immune imbalance where pro-inflammatory CD4(+) T-cells are increased and T regulatory cells (Tregs) are decreased. This imbalance leads to chronic inflammation characterized by oxidative stress, pro-inflammatory cytokines and autoantibodies. Studies conducted in our laboratory have demonstrated the importance of this immune imbalance in causing hypertension in response to placental ischaemia in pregnant rats. These studies confirm that increased CD4(+) T-cells and decreased Tregs during pregnancy leads to elevated inflammatory cytokines, endothelin (ET-1), reactive oxygen species (ROS) and agonistic autoantibodies to the angiotensin II (Ang II), type 1 receptor (AT1-AA). All of these factors taken together play an important role in increasing the blood pressure during pregnancy. Specifically, this review focuses on the decrease in Tregs, and their associated regulatory cytokine interleukin (IL)-10, which is seen in response to placental ischaemia during pregnancy. This study will also examine the effect of regulatory immune cell repopulation on the pathophysiology of PE. These studies show that restoring the balance of the immune system through increasing Tregs, either by adoptive transfer or by infusing IL-10, reduces the blood pressure and pathophysiology associated with placental ischaemia in pregnant rats.

Glucose, insulin, and oxygen interplay in placental hypervascularisation in diabetes mellitus

The placental vasculature rapidly expands during the course of pregnancy in order to sustain the growing needs of the fetus. Angiogenesis and vascular growth are stimulated and regulated by a variety of growth factors expressed in the placenta or present in the fetal circulation. Like in tumors, hypoxia is a major regulator of angiogenesis because of its ability to stimulate expression of various proangiogenic factors. Chronic fetal hypoxia is often found in pregnancies complicated by maternal diabetes as a result of fetal hyperglycaemia and hyperinsulinemia. Both are associated with altered levels of hormones, growth factors, and proinflammatory cytokines, which may act in a proangiogenic manner and, hence, affect placental angiogenesis and vascular development. Indeed, the placenta in diabetes is characterized by hypervascularisation, demonstrating high placental plasticity in response to diabetic metabolic derangements. This review describes the major regulators of placental angiogenesis and how the diabetic environment in utero alters their expression. In the light of hypervascularized diabetic placenta, the focus was placed on proangiogenic factors.

Prolactin and proinflammatory cytokine expression at the fetomaternal interface in first trimester miscarriage

OBJECTIVE

To investigate the expression of prolactin (PRL), PRL-receptor (PRL-R), and the TH1 cytokines interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) at the maternofetal interface.

DESIGN

Case-control study.

SETTING

University hospital unit of gynecology and obstetrics and research laboratories.

PATIENT(S)

Women undergoing suction curettage for spontaneous miscarriage (study group) and voluntary termination of pregnancy (control group) in the first trimester.

INTERVENTION(S)

Samples of decidua and villi collected and histologically examined at the time of suction curettage.

MAIN OUTCOME MEASURE(S)

Evaluation of all villous samples for karyotype with only euploid cases included; detection of transcripts of PRL, PRL-R, TNF-α, IFN-γ, and IL-2 by qualitative reverse-transcriptase-polymerase chain reaction (RT-PCR); investigation of pattern and site of expression by immunohistochemistry.

RESULT(S)

In both groups, PRL-R and IFN-γ were broadly expressed. The expression of PRL was impaired or absent in the villi of the study group compared with controls. Expression of TNF-α was reduced, although not statistically significantly, in both decidual and villous samples of the study group. Immunohistochemical analysis showed the lack of IL-2 expression in decidual specimens of the control group versus the full expression shown in the study group.

CONCLUSION(S)

Our results highlight the correspondence between PRL expression and vital pregnancy and the involvement of the TH1 cytokines with different specific roles at the implantation site. Prolactin and IL-2 may reciprocally influence expression.

Zinc and pregnancy: Marked changes on the immune response following zinc therapy for pregnant females challenged with Trypanosoma cruzi

BACKGROUND & AIMS

The occurrence of infectious disease processes during pregnancy has significant effects on maternal health and can lead to adverse pregnancy outcomes. The aim of the present study was to examine the potential role of zinc treatment during Trypanosoma cruzi infection in pregnant animals.

METHODS

Female Wistar rats weighing 180-200 g were used in all experiments. Production of nitric oxide, peritoneal macrophages counts, and concentrations of IFN-γ and TNF-α were measured, and the potential protective effects of zinc on fetal development were assessed at 14-day post-infection.

RESULTS

Nitric oxide concentrations were higher in pregnant zinc-treated animals than in their untreated counterparts, despite similar levels of the macrophages, IFN-γ and TNF-α. Zinc therapy was associated with a significant reduction in parasitemia and cardiac parasite burden. Higher placental and birth weights were observed in animals given prenatal zinc supplementation compared to untreated animals.

CONCLUSIONS

These data confirm the critical importance of adequate zinc intake during the peri-conceptional period and indicate that zinc has an effective role in preventing adverse outcomes of pregnancy and reducing the risk of common infections such as Chagas' disease.

Immunomodulator expression in trophoblasts from the feline immunodeficiency virus (FIV)-infected cat

Background

FIV infection frequently compromises pregnancy under experimental conditions and is accompanied by aberrant expression of some placental cytokines. Trophoblasts produce numerous immunomodulators that play a role in placental development and pregnancy maintenance. We hypothesized that FIV infection may cause dysregulation of trophoblast immunomodulator expression, and aberrant expression of these molecules may potentiate inflammation and compromise pregnancy. The purpose of this project was to evaluate the expression of representative pro-(TNF-α, IFN-γ, IL-1β, IL-2, IL-6, IL-12p35, IL-12p40, IL-18, and GM-CSF) and anti-inflammatory cytokines (IL-4, IL-5, and IL-10); CD134, a secondary co-stimulatory molecule expressed on activated T cells (FIV primary receptor); the chemokine receptor CXCR4 (FIV co-receptor); SDF-1α, the chemokine ligand to CXCR4; and FIV gag in trophoblasts from early-and late-term pregnancy.

Methods

We used an anti-cytokeratin antibody in immunohistochemistry to identify trophoblasts selectively, collected these cells using laser capture microdissection, and extracted total RNA from the captured cell populations. Real time, reverse transcription-PCR was used to quantify gene expression.

Results

We detected IL-4, IL-5, IL-6, IL-1β, IL-12p35, IL-12p40, and CXCR4 in trophoblasts from early-and late-term pregnancy. Expression of cytokines increased from early to late pregnancy in normal tissues. A clear, pro-inflammatory microenvironment was not evident in trophoblasts from FIV-infected queens at either stage of pregnancy. Reproductive failure was accompanied by down-regulation of both pro-and anti-inflammatory cytokines. CD134 was not detected in trophoblasts, and FIV gag was detected in only one of ten trophoblast specimens collected from FIV-infected queens.

Conclusion

Feline trophoblasts express an array of pro-and anti-inflammatory immunomodulators whose expression increases from early to late pregnancy in normal tissues. Non-viable pregnancies were associated with decreased expression of immunomodulators which regulate trophoblast invasion in other species. The detection of FIV RNA in trophoblasts was rare, suggesting that the high rate of reproductive failure in FIV-infected queens was not a direct result of viral replication in trophoblasts. The influence of placental immune cells on trophoblast function and pregnancy maintenance in the FIV-infected cat requires additional study.

Cytokine dysregulation in early- and late-term placentas from feline immunodeficiency virus (FIV)-infected cats

PROBLEM

Experimental infection of cats with FIV-B-2542 produces high rates of fetal infection and reproductive failure. We hypothesized that dysregulation of placental cytokine expression occurs in FIV-infected queens, and aberrant expression potentiates inflammation and impacts pregnancy outcome. Our purpose was to quantify expression of representative pro-inflammatory cytokines (IL-6, IL-12p35, and IL-1β), IL-10 (anti-inflammatory), and the chemokine SDF-1α in early- and late-term placental tissues.

METHOD OF STUDY

 Real-time reverse transcriptase PCR was used to measure gene expression in placental tissues.

RESULTS

 Increased expression of IL-6 and IL-12p35 and decreased expression of IL-10 occurred in FIV-infected tissues at early pregnancy; at late gestation, IL-6 expression increased and IL-1β and SDF-1α decreased. At late pregnancy, IL-6 expression positively correlated with FIV load. IL-12:IL-10 ratios were higher in infected tissues at early, but not late pregnancy. Fetal non-viability accompanied decreased IL-12p35 and SDF-1α expression at both stages and decreased IL-12:IL-10 ratio at late pregnancy.

CONCLUSION

FIV infection caused a pro-inflammatory placental microenvironment at early, but not late pregnancy.

Role of placentally produced inflammatory and regulatory cytokines in pregnancy and the etiology of preeclampsia

Human pregnancy is a metabolic and immune challenge for the mother who has to accommodate in her womb a semi-allogeneic fetus whose energy needs increase tremendously with gestation. Recent compelling research has suggested that proper inflammatory changes and oxidative balance are a requisite for successful pregnancy. The placenta is an integral component of this inflammatory response as it actively produces a variety of cytokines and immunomodulatory hormones. In preeclampsia, a life-threatening disorder of pregnancy that is characterized by widespread damage and dysfunction of the maternal endothelium, placental oxidative stress and aberrant cytokine expression induces an exaggerated maternal systemic inflammatory response to pregnancy.

Th1/Th2 cytokines balance--yin and yang of reproductive immunology

For years conception of Th2 overbalance during pregnancy has been a paradigm for immunology of reproduction, while Th1 activity has been presented as unwanted component. Studies concerning Th1/Th2 balance in physiological and complicated pregnancy have been reviewed. Th1 activity during early peri-implantation period, premature and term labour not only accompanies but even predominates over Th2 activity. Th1 activity plays important role in promotion of Th2 response, regulation of placentation process, defense against infections and initiation of delivery. Together with Th2 activity it is necessary component of immunological reactions during pregnancy, both activities being inseparable like yin and yang. So paradigm of "Th1-Th2 cooperation" is much closer to reality than "Th2 phenomenon".

Enhanced expressions of endometrial tumour necrosis factor alpha and its receptors during early pregnancy in bonnet monkeys

Tumour necrosis factor alpha (TNF-alpha), a pro-inflammatory cytokine may play an active role in stimulating inflammatory reactions during pregnancy. However, the expression of endometrial TNF-alpha has not been investigated especially during early pregnancy, a phenomenon invariably accompanied by inflammatory reaction. In the present study, the endometrial expressions of TNF-alpha and its receptors (TNFR1 and TNFR2) during early pregnancy, when the embryo lies free in the zona hatched state in the uterine lumen, were analyzed by immunohistochemistry. The endometrial expressions of TNF-alpha, TNFR1 and TNFR2 were found to be significantly up-regulated (p < 0.05) in the glandular epithelium on day 6 post-ovulation in pregnant animals. The alteration in the expression of these molecules may contribute to the induction of local inflammatory reactions during implantation.

Macrophages and apoptotic cell clearance during pregnancy

BACKGROUND

During implantation, apoptosis is critical for the appropriate tissue remodeling of the maternal decidua and invasion of the developing embryo, yet the regulation of apoptosis is also imperative for a successful pregnancy. The quick and effective removal of apoptotic cells by tissue macrophages represents an essential process, which prevents the release of self-antigens, and in the case of pregnancy, paternal alloantigens.

METHODS OF STUDY

Recent studies have shown that the process of apoptotic cell clearance is not a neutral event, but rather an active one that induces macrophage production of anti-inflammatory cytokines and survival factors. Apoptotic cell clearance is, therefore, necessary for the resolution of inflammatory conditions, which during pregnancy could have lethal consequences.

CONCLUSIONS

The function of the maternal immune system during implantation and throughout pregnancy is, therefore, an important area of investigation. This review will discuss the role of decidual macrophages in apoptotic cell clearance during pregnancy.

Potential role of macrophages as immunoregulators of pregnancy

The role of the maternal immune system during pregnancy has focused mainly on the aspect of immune tolerance to the invading trophoblast and, therefore, fetus. While this is a critical aspect of reproductive immunology, it is also important to consider the function of the maternal immune system in the promotion of implantation and maintenance of pregnancy. Apoptosis or cell death is not the final stage in tissue development. The quick and effective removal of apoptotic cells by tissue macrophages represents a vital process preventing "leak" of self-antigens and promoting the production of proliferative/survival factors. One of the key requirements of apoptotic cell clearance is the resolution of inflammatory conditions, which, as in the case of pregnancy, may have lethal consequences. This review will focus on decidual macrophages and their role on apoptosis and cell clearance during pregnancy.

Differential regulation and function of the Fas/Fas ligand system in human trophoblast cells

Trophoblast rejection, which is characterized by increased apoptosis, is mediated by T helper (Th)-1, or proinflammatory, cytokines, whereas Th-2, or anti-inflammatory, cytokines confer immune protection and facilitate implantation. We investigated the role of both types of cytokines on the expression and function of the Fas/Fas ligand (FasL) apoptotic pathway in trophoblast cells. First-trimester human trophoblast primary-culture cells as well as A3 and HTR/8 trophoblast cell lines were treated with proinflammatory cytokines such as interferon-gamma (IFN-gamma) and tumor necrosis factor alpha (TNFalpha) and with the anti-inflammatory cytokines interleukin (IL)-6 and IL-10. Sensitivity to Fas-mediated apoptosis was measured using an activating anti-Fas monoclonal antibody. Cell viability was evaluated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) and CellTiter 96 assay. Fas/FasL mRNA and protein expression levels were determined using reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis, respectively. Trophoblast cells normally express FasL, but low levels of Fas, and they are resistant to Fas-mediated apoptosis. IFN-gamma and TNFalpha promote Fas expression and sensitivity, whereas IL-6 and IL-10 increase the resistance of trophoblast cells to Fas-mediated apoptosis. Furthermore, IL-10 treatment activates FLICE-like inhibitory protein (FLIP), a downstream inhibitor of Fas apoptotic signaling. Although trophoblast cells express Fas, susceptibility to Fas does not necessarily correlate with its expression. In this study, we demonstrate that Th-2 cytokines increase the resistance of trophoblast cells to Fas-mediated apoptosis either by inhibiting Fas expression or by inducing FLIP activation. This "trophoblast-cytokine-Fas/FasL triad" determines the ability of the Fas/FasL system to regulate trophoblast viability and, consequently, the success or failure of pregnancy.

Cytokines of the placenta and extra-placental membranes: biosynthesis, secretion and roles in establishment of pregnancy in women

Virtually all known cytokines have been demonstrated to be expressed in the placenta and associated fetal and maternal membranes during normal gestation. In addition to playing their traditional roles as modulators of immunological function, cytokines derived from the placenta and extraplacental membranes, together with other locally-derived growth factors, appear to be implicated in various aspects of implantation and placental development. Imbalances in the intrauterine cytokine milieu around the time of implantation and invasion may play a causative role in disorders associated with early pregnancy failure, and are also associated with the abnormal trophoblast development seen in gestational trophoblastic disease. Cytokines thus appear to be an important component of a paracrine/autocrine communication network operating within the feto-maternal interface to ensure the successful establishment of pregnancy.

Biological characterization of three novel variants of IFN-alpha 13 produced by human placental trophoblast

Interferon (IFN)-alpha from the human placenta was cloned and expressed with the aim to study the antiviral, antiproliferative, and immunostimulatory activities. In the present study, we describe three previously unknown sequence variants of IFN-alpha 13 originating from the villous trophoblast. The first variant differed from IFN-alpha 13 by a Cys99Arg substitution and a 10-amino acid C-terminal deletion, which led to a severe reduction of the antiviral and antiproliferative potential. The second variant with a Glu32Tyr substitution also displayed diminished antiviral and antiproliferative properties, but to a lesser extent than the first clone. For the third variant, a Ser25Pro substitution in the N-terminal part of the protein and two substitutions in the C-terminal part of the protein, Arg126Gly and Ala140Gly, resulted in diminished antiviral but not antiproliferative properties. Regardless of the altered antiviral and antiproliferative properties, all sequence variants demonstrated natural killer (NK) cell stimulatory potentials paralleling that of prototype IFN-alpha 13. Further studies are needed to gain a better understanding of the functional significance of different IFN-alpha subtypes at the maternal-fetal interface, in particular in light of the controversial role the NK cells play in the positive outcome of pregnancy.

Amniocentesis and chorionic villus sampling

Invasive prenatal diagnosis continues to be the gold standard for pregnancies at increased risk of chromosomal aneuploidy or other genetic disease. Chorionic villus sampling is the procedure of choice for the first trimester. Early amniocentesis has been shown to carry increased risks of pregnancy loss, amniotic fluid leakage and talipes equinovarus. Mid-trimester amniocentesis continues to be the most common form of invasive prenatal diagnosis, with post-procedural loss rates of between 0.5 and 1%. This present review summarizes information on technique risks, looks at new technology applied to invasive prenatal diagnosis testing, and reports on new diagnoses that could be made either by amniocentesis or chorionic villus sampling.

Expression of the placental cytokines tumor necrosis factor alpha, interleukin 1beta, and interleukin 10 is increased in preeclampsia

OBJECTIVE

We sought to determine whether placental cytokine expression is altered in patients with preeclampsia.

STUDY DESIGN

Whole placental tissue was collected at cesarean delivery, and total ribonucleic acid was extracted. Reverse transcriptase-polymerase chain reaction was performed to determine cytokine expression. Product bands were quantitated by scanning densitometry, and results were expressed as a ratio of cytokine/housekeeping gene (cytokine expression index). Statistical analysis was performed by the Student t test and the Mann-Whitney U test.

RESULTS

Placentas from 6 patients with preeclampsia and 4 normotensive patients were analyzed. Placental expression of interleukin 1beta and interleukin 10 was greater in preeclamptic women than in normotensive subjects (median interleukin 1beta cytokine expression index, 0.675; range, 0.394-0. 953; vs 0.106; range, 0.084-0.166; P =.011; median interleukin 10 cytokine expression index, 1.042; range, 0.672-1.192; vs 0.126; range, 0.062-0.398; P <.011). Tumor necrosis factor alpha messenger ribonucleic acid was detected in placentas of preeclamptic subjects but not in normotensive control subjects.

CONCLUSION

Placentas from preeclamptic patients demonstrated increased expression of interleukin 1beta, interleukin 10, and tumor necrosis factor alpha. This may be in association with placental hypoxia and may contribute to the global endothelial dysfunction observed in preeclampsia.