Cytokine production in chorioamnionitis

Decidual Cells Block Inflammation-Mediated Inhibition of 15-Hydroxyprostaglandin Dehydrogenase in Trophoblasts

Chorioamnionitis generates prostaglandin (PG) E2 and F2α, promoting fetal membrane rupture, cervical ripening, and uterine contractions. 15-Hydroxyprostaglandin dehydrogenase (HPGD) contributes to pregnancy maintenance by inactivating PGs. Herein, the role of decidual cells in the regulation of HPGD expression at the maternal-fetal interface was investigated. HPGD immunostaining was primarily detected in anchoring villi and choriodecidual extravillous trophoblasts (EVTs) during pregnancy. Chorionic EVTs adjacent to the decidua parietalis exhibited significantly higher HPGD levels than those adjacent to the amnion. HPGD histologic score levels were significantly lower in choriodecidua from chorioamnionitis versus gestational age-matched controls (means ± SEM, 132.6 ± 3.8 versus 31.2 ± 7.9; P < 0.05). Conditioned media supernatant (CMS) from in vitro decidualized term decidual cells (TDCs) up-regulated HPGD levels in differentiated EVTs, primary trophoblasts, and HTR8/SVneo cells. However, CMS from 5 μg/mL lipopolysaccharide or 10 ng/mL IL-1β pretreated TDC cultures down-regulated HPGD levels in HTR8/SVneo cultures. Similarly, direct treatment of HTR8/SVneo with lipopolysaccharide or IL-1β significantly reduced HPGD levels versus control (P < 0.05) but not in TDC-CMS pretreated HTR8/SVneo cultures. Collectively, these results uncover a novel decidual cell-mediated paracrine mechanism that stimulates levels of trophoblastic HPGD, whose function is to inactivate labor-inducing PGs, thereby promoting uterine quiescence during pregnancy. However, infectious/inflammatory stimuli in decidual cells cause a paracrine inhibition of trophoblastic HPGD expression, increasing PGE2/PGF2α levels, thereby contributing to preterm birth.

Systemic Cytokines in Retinopathy of Prematurity

Retinopathy of prematurity (ROP), a vasoproliferative vitreoretinal disorder, is the leading cause of childhood blindness worldwide. Although angiogenic pathways have been the main focus, cytokine-mediated inflammation is also involved in ROP etiology. Herein, we illustrate the characteristics and actions of all cytokines involved in ROP pathogenesis. The two-phase (vaso-obliteration followed by vasoproliferation) theory outlines the evaluation of cytokines in a time-dependent manner. Levels of cytokines may even differ between the blood and the vitreous. Data from animal models of oxygen-induced retinopathy are also valuable. Although conventional cryotherapy and laser photocoagulation are well established and anti-vascular endothelial growth factor agents are available, less destructive novel therapeutics that can precisely target the signaling pathways are required. Linking the cytokines involved in ROP to other maternal and neonatal diseases and conditions provides insights into the management of ROP. Suppressing disordered retinal angiogenesis via the modulation of hypoxia-inducible factor, supplementation of insulin-like growth factor (IGF)-1/IGF-binding protein 3 complex, erythropoietin, and its derivatives, polyunsaturated fatty acids, and inhibition of secretogranin III have attracted the attention of researchers. Recently, gut microbiota modulation, non-coding RNAs, and gene therapies have shown promise in regulating ROP. These emerging therapeutics can be used to treat preterm infants with ROP.

Infections During Pregnancy and Risks for Adult Psychosis: Findings from the New England Family Study

For the past 40 years, our team has conducted a unique program of research investigating the prenatal risks for schizophrenia and related adult psychiatric disorders. The New England Family Study is a long-term prospective cohort study of over 16,000 individuals followed from the prenatal period for over 50 years. This chapter summarizes several major phases and findings from this work, highlighting recent results on maternal prenatal bacterial infections and brain imaging. Implications regarding the causes and potential prevention of major psychotic disorders are discussed.

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.

The Expression of IL-1β Correlates with the Expression of Galectin-3 in the Tissue at the Maternal-Fetal Interface during the Term and Preterm Labor

The inflammatory processes that occur at the maternal−fetal interface are considered one of the factors that are responsible for preterm birth. The pro-inflammatory roles of the Gal-3-induced activation of NLRP3 inflammasome and the consecutive production of IL-1β have been described in several acute and chronic inflammatory diseases, but the role of this inflammatory axis in parturition has not been studied. The aim of this study was to analyze the protein expression of Gal-3, NLRP3, and IL-1β in the decidua, villi, and fetal membranes, and to analyze their mutual correlation and correlation with the clinical parameters of inflammation in preterm birth (PTB) and term birth (TB). The study included 40 women that underwent a preterm birth (gestational age of 25.0−36.6) and histological chorioamnionitis (PTB) and control subjects, 22 women that underwent a term birth (gestational age of 37.0−41.6) without histological chorioamnionitis (TB). An analysis of the tissue sections that were stained with anti- Gal-3, -NLRP3, and -IL-1β antibodies was assessed by three independent investigators. The expression levels of Gal-3 and IL-1β were significantly higher (p < 0.001) in the decidua, villi, and fetal membranes in the PTB group when they compared to those of the TB group, while there was no difference in the expression of NLRP3. A further analysis revealed that there was no correlation between the protein expression of NLRP3 and the expression of Gal-3 and IL-1β, but there was a correlation between the expression of Gal-3 and IL-1β in decidua (R = 0.401; p = 0.008), villi (R = 0.301; p = 0.042) and the fetal membranes (R = 0.428; p = 0.002) in both of the groups, PTB and TB. In addition, the expression of Gal-3 and IL-1β in decidua and the fetal membranes was in correlation with the parameters of inflammation in the maternal and fetal blood (C-reactive protein, leukocyte number, and fibrinogen). The strong correlation between the expression of Gal-3 and IL-1β in the placental and fetal tissues during labor indicates that Gal-3 may participate in the regulation of the inflammatory processes in the placenta, leading to increased production of IL-1β, a cytokine that plays the main role in both term and preterm birth.

Chorioamnionitis has no impact on immunohistochemical expression of IL-6 in placental membranes of the late preterm delivery regardless of the membrane status

OBJECTIVES

To compare the immunohistochemical expression of IL-6 in placental membranes of late preterm delivery in women with histologically proven chorioamnionitis with and without preterm premature rupture of membranes (PPROM).

METHODS

Fetal membranes were collected from 60 women who had late preterm delivery with histologic chorioamnionitis with and without PPROM (30 in each group). Immunohistochemistry for IL-6 was performed on formalin fixed and paraffin-embedded sections. The two groups were matched for age, body mass index and parity. SPSS Version 17.0 was used for statistical analysis.

RESULTS

There was no difference in immunohistochemical expression of IL-6 in placental membranes of women with histologic chorioamnionitis regardless of the membrane status.

CONCLUSIONS

Chorioamnionitis has no impact on immunohistochemical expression of IL-6 in placental membranes of women with late preterm delivery despite the clinical presentation.

Molecular and endocrine mechanisms involved in preterm birth

Preterm birth is a worldwide social problem. Incidence rates may vary from 5 to 18% of all deliveries, with important differences observed between developed and developing countries. Preterm birth has a negative impact on newborns and neonatal mortality and morbidity are high. Despite improvements in modern neonatal care, we know little of the mechanisms that determine the onset and development of preterm birth. Infections seem to be one the most important triggers, determining the activation of protective mechanisms aimed at ending the pregnancy and safeguarding the health of the woman. However, threatened preterm birth often occurs even in women who do not have any ongoing infectious process. Of these, which are the majority, the causes and the activation mechanisms remain unknown or unclear; however, there are several molecular and endocrine mechanisms that finally lead to preterm birth. In this review, we seek to shed light and summarize the molecular and endocrine mechanisms underlying the development of preterm birth. Their understanding could help us to understand the dynamics of premature birth but, above all, to allow an early diagnosis and primary prevention of the problem.

Translational insights into mechanisms and preventive strategies after renal injury in neonates

Adverse perinatal circumstances can cause acute kidney injury (AKI) and contribute to chronic kidney disease (CKD). Accumulating evidence indicate that a wide spectrum of perinatal conditions interferes with normal kidney development and ultimately leads to aberrant kidney structure and function later in life. The present review addresses the lack of mechanistic knowledge with regard to perinatal origins of CKD and provides a comprehensive overview of pre- and peri-natal insults, including genetic predisposition, suboptimal nutritional supply, obesity and maternal metabolic disorders as well as placental insufficiency leading to intrauterine growth restriction (IUGR), prematurity, infections, inflammatory processes, and the need for life-saving treatments (e.g. oxygen supplementation, mechanical ventilation, medications) in neonates. Finally, we discuss future preventive, therapeutic, and regenerative directions. In summary, this review highlights the perinatal vulnerability of the kidney and the early origins of increased susceptibility toward AKI and CKD during postnatal life. Promotion of kidney health and prevention of disease require the understanding of perinatal injury in order to optimize perinatal micro- and macro-environments and enable normal kidney development.

Grim-19 deficiency promotes decidual macrophage autophagy in recurrent spontaneous abortion

Dysregulation of decidual macrophages leads to the occurrence of recurrent spontaneous abortion (RSA). However, the role of macrophages in RSA occurrence remains unclear. In this study, we found that the expression of Grim-19 was decreased, and the expression of autophagy related proteins Beclin1, LC3B II/I and BNIP3 was markedly upregulated in decidual macrophages of RSA patients compared with the normal pregnancy group. Furthermore, we demonstrated that downregulation of GRIM-19 increased the expression of autophagy related proteins Beclin1, LC3B II/I, BNIP3 and the proinflammatory cytokines IL1B, IL6 and TNFa in uterine mononuclear cells of GRIM-19^+/- mice. The proportion of CD45+CD11b+F4/80+LC3B+ cells in GRIM-19^+/- mouse uteri was significantly higher than that in WT mouse uteri. In addition, we confirmed that inhibition of Grim-19 by siRNA enhanced the expression of autophagy related proteins in RAW264.7 cells and THP-1 cells. More importantly, downregulation of Grim-19 in RAW264.7 cells promoted the release of proinflammatory cytokines and promoted phagocytic activity, which could be reversed by autophagy blockade. For THP-1-derived macrophages, the results of RNA-seq suggested that Grim-19 mainly modulates immune and inflammatory-related pathways, leading to cytokine production, and thus contributing to inflammation. Therefore, our data reveal that Grim-19 deficiency influences macrophage function, characterized by enhanced proinflammatory cytokines and phagocytic activity, and this might be regulated by autophagy. This may represent a novel mechanism for the occurrence of RSA.

A Systematic Review of the Safety of Blocking the IL-1 System in Human Pregnancy

Blockade of the interleukin-1 (IL-1) pathway has been used therapeutically in several inflammatory diseases including arthritis and cryopyrin-associated periodic syndrome (CAPS). These conditions frequently affect women of childbearing age and continued usage of IL-1 specific treatments throughout pregnancy has been reported. IL-1 is involved in pregnancy complications and its blockade could have therapeutic potential. We systematically reviewed all reported cases of IL-1 blockade in human pregnancy to assess safety and perinatal outcomes. We searched several databases to find reports of specific blockade of the IL-1 pathway at any stage of pregnancy, excluding broad spectrum or non-specific anti-inflammatory intervention. Our literature search generated 2439 references of which 22 studies included, following extensive review. From these, 88 different pregnancies were assessed. Most (64.8%) resulted in healthy term deliveries without any obstetrical/neonatal complications. Including pregnancy exposed to Anakinra or Canakinumab, 12 (15.0%) resulted in preterm birth and one stillbirth occurred. Regarding neonatal complications, 2 cases of renal agenesis (2.5%) were observed, and 6 infants were diagnosed with CAPS (7.5%). In conclusion, this systematic review describes that IL-1 blockade during pregnancy is not associated with increased adverse perinatal outcomes, considering that treated women all presented an inflammatory disease associated with elevated risk of pregnancy complications.

Methylation Status of the miR-141-3p Promoter Regulates miR-141-3p Expression, Inflammasome Formation, and the Invasiveness of HTR-8/SVneo Cells

MicroRNA-141 (miR-141-3p) is upregulated in preeclampsia. This study investigated the effect of methylation of the miR-141-3p promoter on cell viability, invasion capability, and inflammasomes in vitro. The expression of miR-141-3p and methylation status of the miR-141-3p promoter were examined by RT-qPCR and pyrosequencing in villus tissues of women with spontaneous delivery (VTsd), villus tissues of women with preeclampsia (VTpe), and also in HTR-8/SVneo cells treated with a miR-141-3p inhibitor and 20 μmol/L 5-aza-2'-deoxycytidine (5-Aza), a DNA methyltransferase inhibitor. Cell viability and invasion were evaluated by CCK-8 and transwell assays. In addition, the levels of CXCL12, CXCR4, CXCR2, MMPs, NLRP3, and ASC expression were assessed by western blotting, and IL-1β and IL-18 concentrations were assayed by ELISA. miR-141-3p expression was upregulated, and the levels of miR-141-3p promoter methylation and CXCL12, CXCR4, and CXCR2 expression were decreased in VTpe relative to VTsd. In HTR-8/SVneo cells, hypomethylation caused by 5-Aza treatment increased miR-141-3p expression, while DNA methyltransferase 3 (DNMT3) transfection decreased miR-141-3p expression. miRNA-141-3p induced NLRP3, IL-1β, and IL-18 production, decreased CXCR4, MMP, and MMP2 production, and suppressed cell growth and invasion. Furthermore, we observed that NLRP3 plays an important mediatory role in the effects of miR-141-3p described above. Decreased methylation of the miR-141-3p promoter increases miR-141-3p expression, which in turn increases NLRP3 expression, resulting in higher IL-1β and IL-18 levels and lower levels of MMP2/9 and CXCR4. We conclude that modification of the miR-141-3p promoter might be a curial mediator in preeclampsia.

Prenatal administration of IL-1Ra attenuate the neurodevelopmental impacts following non-pathogenic inflammation during pregnancy

Prenatal inflammation negatively affects placental function, subsequently altering fetal development. Pathogen-associated molecular patterns (PAMPs) are used to mimics infections in preclinical models but rarely detected during pregnancy. Our group previously developed an animal model of prenatal exposure to uric acid (endogenous mediator), leading to growth restriction alongside IL-1-driven placental inflammation (Brien et al. in J Immunol 198(1):443–451, 2017). Unlike PAMPs, the postnatal impact of prenatal non-pathogenic inflammation is still poorly understood. Therefore, we investigated the effects of prenatal uric acid exposure on postnatal neurodevelopment and the therapeutic potential of the IL-1 receptor antagonist; IL-1Ra. Uric acid induced growth restriction and placental inflammation, which IL-1Ra protected against. Postnatal evaluation of both structural and functional aspects of the brain revealed developmental changes. Both astrogliosis and microgliosis were observed in the hippocampus and white matter at postnatal day (PND)7 with IL-1Ra being protective. Decreased myelin density was observed at PND21, and reduced amount of neuronal precursor cells was observed in the Dentate Gyrus at PND35. Functionally, motor impairments were observed as evaluated with the increased time to fully turn upward (180 degrees) on the inclined plane and the pups were weaker on the grip strength test. Prenatal exposure to sterile inflammation, mimicking most clinical situation, induced growth restriction with negative impact on neurodevelopment. Targeted anti-inflammatory intervention prenatally could offer a strategy to protect brain development during pregnancy.

Marked up-regulation of anti inflammatory cytokine gene expression in the peripheral blood mononuclear cells of postpartum cows with endometritis

This study was designed to determine the mRNA expression profile of inflammatory and anti-inflammatory cytokines in peripheral blood mononuclear cells (PBMC) of endometritic and non-endometritic cows to find out a possible marker for diagnosis of endometritis. Cows (21) including 12 endometritic, and 9 normal (non-endometritic) that did not develop uterine diseases postpartum (pp) were selected. Expression profile (mRNA) of cytokines, viz. IL-1β, TNFα, IL-8 and IL-4 in endometritic cows relative to non-endometritic was studied in PBMC isolated from the blood of the cows collected within 4 to 5 weeks pp. Fold difference (n-fold) in cytokine gene expression in the PBMC of endometritic cows relative to normal was calculated using relative quantification method (2-ΔΔCt). The relative fold change in gene expression for IL-1 was significantly lower in endometritic animals (0.31) than in cows that did not develop endometritis. Significant up-regulation was noted for the proinflammatory cytokine TNFα (9.53 fold and anti-inflammatory cytokine IL-4 (90.09) in cows suffering from endometritis relative to nonendometritic cows. Up-regulation of chemokine IL-8 gene (6.25 fold; was also observed in endometritic compared to non-endometritic cows. Highest and significant up-regulation of mRNA expression for IL-4 followed by TNFα in PBMC of endometritic cows recorded in the study may indicate the development of endometritis in postpartum cows.

Polymicrobial stimulation of human fetal membranes induce neutrophil activation and neutrophil extracellular trap release

Preterm birth is a major contributor to neonatal mortality and morbidity. While the causes of preterm birth remain incompletely understood, infection is a major risk factor, and chorioamnionitis is commonly observed. Chorioamnionitis is characterized by inflammation and neutrophil infiltration of the fetal membranes (FM). We recently reported that human FMs which had been exposed to low levels of bacterial lipopolysaccharide (LPS) recruit neutrophils and activate them, increasing their secretion of pro-inflammatory cytokines, degranulation of myeloperoxidase (MPO), and release of neutrophil extracellular traps (NETs). Herein, we demonstrate that conditioned media (CM) from viral dsRNA (Poly(I:C))-stimulated FMs also increased neutrophil migration, and induced the secretion of inflammatory IL-8 and the release of NETs. Furthermore, CM from FMs stimulated by a combination of bacterial LPS and Poly(I:C) augmented neutrophil NET release, compared to CM from FMs stimulated with either Poly(I:C) or LPS alone. NETs induced by FMs exposed to Poly(I:C), with or without LPS, were released and degraded quicker than those induced by resting or LPS-stimulated FM-CM. These findings indicate that FMs exposed to viral dsRNA promote neutrophil recruitment, activation and NET formation, similar to FMs exposed to bacterial LPS alone. However, in response to FM polymicrobial stimulation the levels and kinetics of NET release are augmented. This work builds upon our understanding of how infections at the maternal-fetal interface may affect neutrophil function.

Activated Neutrophils Propagate Fetal Membrane Inflammation and Weakening through ERK and Neutrophil Extracellular Trap-Induced TLR-9 Signaling

Preterm birth is associated with significant neonatal mortality and morbidity worldwide. Chorioamnionitis, inflammation of the fetal membranes (FMs), is a major risk factor and is characterized by neutrophil infiltration. However, the role of neutrophils at the FMs remains unclear. We recently reported that FMs exposed to bacterial LPS recruited more neutrophils compared with resting FMs and activated them to degranulate and release reactive oxygen species, chemokines/cytokines, and neutrophil extracellular traps. We posit that under resting conditions, neutrophils play a protective surveillance role, whereas during infection/inflammation, they induce FM tissue injury. To test this, human FM explants were exposed to neutrophil conditioned media (CM). We demonstrate that CM from neutrophils exposed to resting FM-CM did not affect FM viability or function. Conversely, CM from neutrophils activated by LPS-stimulated FM-CM significantly increased FM secretion of inflammatory IL-6, IL-8, GRO-α, and the markers of membrane weakening, MMP-9 and PGE₂ This FM response was partially mediated by ERK signaling and neutrophil extracellular traps through the activation of the DNA sensor, TLR-9. Thus, neutrophils recruited by FMs during infection can propagate FM inflammation and weakening, acting in a feed-forward mechanism to propagate tissue injury at the maternal-fetal interface, increasing the risk of premature FM rupture and preterm birth in women with intrauterine infection.

Evaluation of leucine-rich alpha-2 glycoprotein as a biomarker of fetal infection

This study aimed to determine the association between umbilical cord leucine-rich alpha-2 glycoprotein (LRG) and fetal infection and investigate the underlying mechanism of LRG elevation in fetuses. We retrospectively reviewed the medical records of patients who delivered at Osaka University Hospital between 2012 and 2017 and selected those with histologically confirmed chorioamnionitis (CAM), which is a common pregnancy complication that may cause neonatal infection. The participants were divided into two groups: CAM with fetal infection (CAM-f[+] group, n = 14) and CAM without fetal infection (CAM-f[−] group, n = 31). Fetal infection was defined by the histological evidence of funisitis. We also selected 50 cases without clinical signs of CAM to serve as the control. LRG concentrations in sera obtained from the umbilical cord were unaffected by gestational age at delivery, neonatal birth weight, nor the presence of noninfectious obstetric complications (all, p > 0.05). Meanwhile, the LRG levels (median, Interquartile range [IQR]) were significantly higher in the CAM-f(+) group (10.37 [5.21–13.7] μg/ml) than in the CAM-f(−) (3.61 [2.71–4.65] μg/ml) or control group (3.39 [2.81–3.93] μg/ml; p < 0.01). The area under the receiver operating characteristic (ROC) curve of LRG for recognizing fetal infection was 0.92 (optimal cutoff, 5.08 μg/ml; sensitivity, 86%; specificity, 88%). In a mouse CAM model established by lipopolysaccharide administration, the fetal LRG protein in sera and LRG mRNA in the liver were significantly higher than those in phosphate-buffered saline (PBS)-administered control mice (p < 0.01). In vitro experiments using a fetal liver-derived cell line (WRL68) showed that the expression of LRG mRNA was significantly increased after interleukin (IL)-6, IL-1β, and tumor necrosis factor- alpha (TNF-α) stimulation (p < 0.01); the induction was considerably stronger following IL-6 and TNF-α stimulation (p < 0.01). In conclusion, LRG is an effective biomarker of fetal infection, and fetal hepatocytes stimulated with inflammatory cytokines may be the primary source of LRG production in utero.

The role of maternal-foetal interface inflammation mediated by NLRP3 inflammasome in the pathogenesis of recurrent spontaneous abortion

INTRODUCTION

Approximately half of the recurrent spontaneous abortions (RSAs) that remain unidentified to date may be closely related to inflammation. Our previous study found excessive NLRP3 inflammasomes in RSA patients. Here, we investigated further the role of inflammasomes in the maternal-foetal interface of RSA patients.

METHODS

Villous and decidual tissues were collected during uterine curettage. The trophoblast cell line TEV-1 was cultured with lipopolysaccharide (LPS) or low molecular weight heparin (LMWH), and then the macrophage cell line RAW264.7 was treated with trophoblast media. The expression and localisation of inflammasomes in tissues and cells were detected, and the migration and proliferation of cells were analysed.

RESULTS

A significantly increased expression of inflammasomes was observed in RSA tissues compared with those in the normal group, and it was more obvious in villous tissues than in decidual tissues. In TEV-1 cells, after LPS stimulation, the expression of inflammasomes was increased, but the cell activity was decreased, whereas in RAW264.7, both expression of inflammasomes and cell activity were increased in the LPS group. In addition, LMWH could inhibit the action of LPS in above cells.

DISCUSSION

In patients experiencing RSA, abnormal inflammatory response might be mediated by NLRP3 inflammasomes on the maternal-foetal interface, which may reduce trophoblast activity and promote macrophage activity, leading to early embryo implantation failure. LMWH is expected to treat RSA patients by blocking this process.

In utero inflammatory challenge induces an early activation of the hepatic innate immune response in late gestation fetal sheep

Chorioamnionitis is associated with inflammatory end-organ damage in the fetus. Tissues in direct contact with amniotic fluid drive a pro-inflammatory response and contribute to this injury. However, due to a lack of direct contact with the amniotic fluid, the liver contribution to this response has not been fully characterized. Given its role as an immunologic organ, we hypothesized that the fetal liver would demonstrate an early innate immune response to an in utero inflammatory challenge. Fetal sheep (131 ± 1 d gestation) demonstrated metabolic acidosis and high cortisol and norepinephrine values within 5 h of exposure to intra-amniotic LPS. Likewise, expression of pro-inflammatory cytokines increased significantly at 1 and 5 h of exposure. This was associated with NF-κB activation, by inhibitory protein IκBα degradation, and nuclear translocation of NF-κB subunits (p65/p50). Corroborating these findings, LPS exposure significantly increased pro-inflammatory innate immune gene expression in fetal sheep hepatic macrophages in vitro. Thus, an in utero inflammatory challenge induces an early hepatic innate immune response with systemic metabolic and stress responses. Within the fetal liver, hepatic macrophages respond robustly to LPS exposure. Our results demonstrate that the fetal hepatic innate immune response must be considered when developing therapeutic approaches to attenuate end-organ injury associated with in utero inflammation.

Drug Transporters Expressed in the Human Placenta and Models for Studying Maternal-Fetal Drug Transfer

Tremendous efforts have been directed to investigate the ontogeny of drug transporters in fetuses, neonates, infants, and children based on their importance for understanding drug pharmacokinetics. During development (ie, in the fetus and newborn infant), there is special interest in transporters expressed in the placenta that modulate placental drug transfer. Many of these transporters can decrease or increase drug concentrations in the fetus and at birth, stressing the relevance of elucidating expression in the placenta and potential gestational age-dependent changes therein. Hence, the main objective of this review was to summarize the current knowledge about expression and ontogeny of transporters in the human placenta in healthy pregnant women. In addition, various in vitro, ex vivo, and in silico models that can be used to investigate placental drug transfer, namely, placental cancer cell lines, ex vivo cotyledon perfusion experiments, and physiologically based pharmacokinetic (PBPK) models, are discussed together with their advantages and shortcomings. A particular focus was placed on PBPK models because these models can integrate different types of information, such as expression data, ontogeny information, and observations obtained from the ex vivo cotyledon perfusion experiment. Such a mechanistic modeling framework may leverage the available information and ultimately help to improve knowledge about the adequacy and safety of pharmacotherapy in pregnant women and their fetuses.

The earlier the gestational age, the greater the intensity of the intra-amniotic inflammatory response in women with preterm premature rupture of membranes and amniotic fluid infection by Ureaplasma species

Objectives To determine the relationship between the intensity of the intra-amniotic inflammatory response and the gestational age at the time of diagnosis in cases with preterm premature rupture of membranes (PROM) and intra-amniotic infection caused by Ureaplasma spp. Methods A retrospective cohort study was conducted which included 71 women with preterm PROM and a positive amniotic fluid culture with Ureaplasma spp. Women with mixed intra-amniotic infections were excluded. The study population was classified into three groups according to gestational age: group 1, <26 weeks (extreme preterm PROM, n = 17); group 2, 26.0-33.9 weeks (moderate preterm PROM, n = 39); group 3, 34.0-36.9 weeks (late preterm PROM, n = 15). The intensity of the intra-amniotic and maternal inflammatory response was compared among the three groups. The intensity of the intra-amniotic inflammatory response was assessed by the concentration of amniotic fluid matrix metalloproteinase-8 (MMP-8) and white blood cell (WBC) count. The maternal inflammatory response was assessed by the concentration of C-reactive protein (CRP) and WBC count in maternal blood at the time of amniocentesis. Results (1) The median values of amniotic fluid MMP-8 concentration and WBC count were the highest in the extreme preterm PROM group and the lowest in the late preterm PROM group (P < 0.001 and P = 0.01, respectively); (2) the intensity of the maternal inflammatory response measured by maternal blood WBC count and CRP concentration was not significantly associated with gestational age at the time of diagnosis. Conclusion The earlier the gestational age at the time of PROM, the higher the intensity of the intra-amniotic inflammatory response in women with preterm PROM and intra-amniotic infection caused by Ureaplasma spp.

Sex-specific maternofetal innate immune responses triggered by group B Streptococci

Group B Streptococcus (GBS) is one of the most common bacteria isolated in human chorioamnionitis, which is a major risk factor for premature birth and brain injuries. Males are at greater risk than females for developing lifelong neurobehavioural disorders, although the origins of this sex bias remain poorly understood. We previously showed that end-gestational inflammation triggered by GBS led to early neurodevelopmental impairments mainly in the male rat progeny. Identifying key inflammatory players involved in maternofetal immune activation by specific pathogens is critical to develop appropriate novel therapeutic interventions. We aimed to map out the GBS-induced profile of innate immune biomarkers in the maternal-placental-fetal axis, and to compare this immune profile between male and female tissues. We describe here that the GBS-induced immune signalling involved significantly higher levels of interleukin (IL)-1β, cytokine-induced neutrophil chemoattractant-1 (CINC-1/CXCL1) and polymorphonuclear cells (PMNs) infiltration in male compared to female maternofetal tissues. Although male - but not female - fetuses presented increased levels of IL-1β, fetuses from both sexes in-utero exposed to GBS had increased levels of TNF-α in their circulation. Levels of IL-1β detected in fetal sera correlated positively with the levels found in maternal circulation. Here, we report for the first time that the maternofetal innate immune signalling induced by GBS presents a sexually dichotomous profile, with more prominent inflammation in males than females. These sex-specific placental and fetal pro-inflammatory responses are in keeping with the higher susceptibility of the male population for preterm birth, brain injuries and neurodevelopmental disorders such as cerebral palsy and autism spectrum disorders.

Lipopolysaccharide-Stimulated Human Fetal Membranes Induce Neutrophil Activation and Release of Vital Neutrophil Extracellular Traps

Preterm birth is a major contributor to neonatal mortality and morbidity, and infection is a major risk factor. Chorioamnionitis, inflammation of the placenta, and fetal membranes (FMs) are commonly observed in preterm birth and are characterized by neutrophil infiltration. However, interactions between FMs and neutrophils remain incompletely understood. The objectives of this study were to determine how FMs, with or without bacterial LPS stimulation, affect neutrophil recruitment, activation, and the formation of neutrophil extracellular traps (NETs) and to elucidate the signaling mechanisms involved. Using a combination of in vitro, ex vivo, and in vivo approaches, we show that human resting FMs can directly recruit neutrophils and induce them to produce proinflammatory factors. Furthermore, neutrophils release vital NETs in response to FM-derived factors. LPS-stimulated FMs further augmented neutrophil recruitment, inflammatory cytokine/chemokine secretion, and vital NET release and also induced reactive oxygen species production and degranulation. We demonstrate a role for FM-derived TNF-α in mediating these effects through activation of neutrophil p38 MAPK. We propose that, during infection, neutrophil recruitment and activation may neutralize pathogens, vital NET formation, and prolonged neutrophil viability, and in combination with degranulation, reactive oxygen species production and inflammatory chemokine/cytokine production may contribute to tissue injury at the maternal/fetal interface.

Vascular changes in fetal growth restriction: clinical relevance and future therapeutics

Fetal growth restriction (FGR) affects about 5-10% pregnancies and is associated with poorer outcomes in the perinatal period. Additionally, long standing epidemiological data support its association with chronic diseases such as hypertension and diabetes. Cardiac and vascular adaptations in response to chronic hypoxemia due to utero-placental insufficiency are hallmarks of fetal adaptations. Investigators have attempted to identify these changes in the placenta at the microscopic and molecular level. The ex vivo dual perfusion model of the placenta enables the study of placental haemodynamics in growth-restricted pregnancies. Persistent arterial abnormalities (thickness and stiffness) noted on vascular ultrasound during fetal life through to the young-adult age group for those affected by FGR, seem to be a plausible link between in utero events and chronic circulatory diseases. Using these, this review reflects current thought on vascular maladaptive changes in the FGR cohorts and the role in investigating current and future therapeutics.

Protein kinase D mediates inflammatory responses of human placental macrophages to Group B Streptococcus

PROBLEM

During pregnancy, Group B Streptococcus (GBS) can infect fetal membranes to cause chorioamnionitis, resulting in adverse pregnancy outcomes. Macrophages are the primary resident phagocyte in extraplacental membranes. Protein kinase D (PKD) was recently implicated in mediating pro-inflammatory macrophage responses to GBS outside of the reproductive system. This work aimed to characterize the human placental macrophage inflammatory response to GBS and address the extent to which PKD mediates such effects.

METHOD

Primary human placental macrophages were infected with GBS in the presence or absence of a specific, small molecule PKD inhibitor, CRT 0066101. Macrophage phenotypes were characterized by evaluating gene expression, cytokine release, assembly of the NLRP3 inflammasome, and NFκB activation.

RESULTS

GBS evoked a strong inflammatory phenotype characterized by the release of inflammatory cytokines (TNFα, IL-1β, IL-6 (P ≤ 0.05), NLRP3 inflammasome assembly (P ≤ 0.0005), and NFκB activation (P ≤ 0.05). Pharmacological inhibition of PKD suppressed these responses, newly implicating a role for PKD in mediating immune responses of primary human placental macrophages to GBS.

CONCLUSION

PKD plays a critical role in mediating placental macrophage inflammatory activation in response to GBS infection.

NLRP7 is increased in human idiopathic fetal growth restriction and plays a critical role in trophoblast differentiation

Fetal growth restriction (FGR) the leading cause of perinatal mortality and morbidity is highly related to abnormal placental development, and placentas from FGR pregnancies are often characterized by increased inflammation. However, the mechanisms of FGR-associated inflammation are far from being understood. NLRP7, a member of a family of receptors involved in the innate immune responses, has been shown to be associated with gestational trophoblastic diseases. Here, we characterized the expression and the functional role of NLRP7 in the placenta and investigated its involvement in the pathogenesis of FGR. We used primary trophoblasts and placental explants that were collected during early pregnancy, and established trophoblast-derived cell lines, human placental villi, and serum samples from early pregnancy (n = 38) and from FGR (n = 40) and age-matched controls (n = 32). Our results show that NLRP7 (i) is predominantly expressed in the trophoblasts during the hypoxic period of placental development and its expression is upregulated by hypoxia and (ii) increases trophoblast proliferation ([³H]-thymidine) and controls the precocious differentiation of trophoblasts towards syncytium (syncytin 1 and 2 and β-hCG production and xCELLigence analysis) and towards invasive extravillous trophoblast (2D and 3D cultures). We have also demonstrated that NLRP7 inflammasome activation in trophoblast cells increases IL-1β, but not IL-18 secretion. In relation to the FGR, we demonstrated that major components of NLRP7 inflammasome machinery are increased and that IL-1β but not IL-18 circulating levels are increased in FGR. Altogether, our results identified NLRP7 as a critical placental factor and provided evidence for its deregulation in FGR. NLRP7 inflammasome is abundantly expressed by trophoblast cells. It is regulated by a key parameter of placental development, hypoxia. It controls trophoblast proliferation, migration, and invasion and exhibits anti-apoptotic role. NLRP7 machinery is deregulated in FGR pregnancies. KEY MESSAGES: NLRP7 inflammasome is abundantly expressed by trophoblast cells. It is regulated by a key parameter of placental development, hypoxia. It controls trophoblast proliferation, migration, and invasion and exhibits anti-apoptotic role. NLRP7 machinery is deregulated in FGR pregnancies.

Glibenclamide inhibits NLRP3 inflammasome-mediated IL-1β secretion in human trophoblasts

Infection-associated pregnancy complications cause premature delivery. Caspase-1 is involved in the maturation of interleukin (IL)-1β, which is activated by the NLRP3 inflammasome. To characterize the significance of the NLRP3 inflammasome pathway in the placenta, the effects of activators and inhibitors on NLRP3-related molecules were examined using isolated primary trophoblasts. Caspase-1 and IL-1β mRNA expression was markedly increased in response to lipopolysaccharide (LPS), a toll-like receptor (TLR)4 ligand. Treatment with the potassium ionophore nigericin significantly increased the level of activated caspase-1. Treatment with either LPS or nigericin stimulated IL-1β secretion, whereas pretreatment with the ATP-sensitive K⁺ channel inhibitor glibenclamide, the Rho-associated coiled-coil kinase inhibitor Y-27632, or a caspase-1 inhibitor significantly decreased nigericin-induced IL-1β secretion. In addition, dibutyryl-cAMP, which induces trophoblast differentiation, decreased expression of NLRP3, caspase-1, and IL-1β. These findings suggest that trophoblasts can secrete IL-1β through the NLRP3/caspase-1 pathway, which is suppressed by glibenclamide, and that the TLR4-mediated NLRP3 inflammasome pathway is more likely to be stimulated in undifferentiated than differentiated trophoblasts. Our data support the hypothesis that inhibition of the NLRP3 inflammasome can suppress placental inflammation-associated disorders.

Role of NF-κB/GATA3 in the inhibition of lysyl oxidase by IL-1β in human amnion fibroblasts

Preterm premature rupture of membranes (pPROMs) account for one-third of preterm births, a leading cause of neonatal death. Understanding the mechanism of membrane rupture is thus of clinical significance in the prevention of preterm birth. Parturition at both term and preterm is associated with increased abundance of proinflammatory cytokines in the fetal membranes regardless of the presence of infection, which is believed to induce rupture of membranes through activation of the matrix metalloproteinases. It remains unknown whether there are any alternative mechanisms underpinning proinflammatory cytokine-induced rupture of membranes. Here we showed that there were reciprocal increases in interleukin-1β (IL-1β) and decreases in lysyl oxidase (LOX), a collagen crosslinking enzyme, in the human amnion tissue following spontaneous rupture of membrane at term and pPROM. Studies using human amnion tissue explants revealed that IL-1β inhibited the expression of LOX, which can be reproduced in cultured human amnion fibroblasts. Mechanistic study revealed that IL-1β inhibited LOX expression through activation of p38 and Erk1/2 mitogen-activated protein kinase pathways, which resulted in the phosphorylation of the nuclear factor kappa light-chain enhancer of activated B (NF-κB) cell subunit p65 as well as GATA binding protein 3 (GATA3). Subsequently, activated NF-κB interacted with GATA3 at the NF-κB binding site of LOX promoter to inhibit its expression. Conclusively, this study has revealed an alternative mechanism that IL-1β may contribute to the rupture of membranes by attenuating collagen crosslinking through downregulation of LOX expression in amnion fibroblasts.

Endoplasmic Reticulum Stress and Homeostasis in Reproductive Physiology and Pathology

The endoplasmic reticulum (ER), comprises 60% of the total cell membrane and interacts directly or indirectly with several cell organelles i.e., Golgi bodies, mitochondria and proteasomes. The ER is usually associated with large numbers of attached ribosomes. During evolution, ER developed as the specific cellular site of synthesis, folding, modification and trafficking of secretory and cell-surface proteins. The ER is also the major intracellular calcium storage compartment that maintains cellular calcium homeostasis. During the production of functionally effective proteins, several ER-specific molecular steps sense quantity and quality of synthesized proteins as well as proper folding into their native structures. During this process, excess accumulation of unfolded/misfolded proteins in the ER lumen results in ER stress, the homeostatic coping mechanism that activates an ER-specific adaptation program, (the unfolded protein response; UPR) to increase ER-associated degradation of structurally and/or functionally defective proteins, thus sustaining ER homeostasis. Impaired ER homeostasis results in aberrant cellular responses, contributing to the pathogenesis of various diseases. Both female and male reproductive tissues undergo highly dynamic cellular, molecular and genetic changes such as oogenesis and spermatogenesis starting in prenatal life, mainly controlled by sex-steroids but also cytokines and growth factors throughout reproductive life. These reproductive changes require ER to provide extensive protein synthesis, folding, maturation and then their trafficking to appropriate cellular location as well as destroying unfolded/misfolded proteins via activating ER-associated degradation mediated proteasomes. Many studies have now shown roles for ER stress/UPR signaling cascades in the endometrial menstrual cycle, ovarian folliculogenesis and oocyte maturation, spermatogenesis, fertilization, pre-implantation embryo development and pregnancy and parturition. Conversely, the contribution of impaired ER homeostasis by severe/prolong ER stress-mediated UPR signaling pathways to several reproductive tissue pathologies including endometriosis, cancers, recurrent pregnancy loss and pregnancy complications associated with pre-term birth have been reported. This review focuses on ER stress and UPR signaling mechanisms, and their potential roles in female and male reproductive physiopathology involving in menstrual cycle changes, gametogenesis, preimplantation embryo development, implantation and placentation, labor, endometriosis, pregnancy complications and preterm birth as well as reproductive system tumorigenesis.

Approaches Mediating Oxytocin Regulation of the Immune System

The hypothalamic neuroendocrine system is mainly composed of the neural structures regulating hormone secretion from the pituitary gland and has been considered as the higher regulatory center of the immune system. Recently, the hypothalamo-neurohypophysial system (HNS) emerged as an important component of neuroendocrine–immune network, wherein the oxytocin (OT)-secreting system (OSS) plays an essential role. The OSS, consisting of OT neurons in the supraoptic nucleus, paraventricular nucleus, their several accessory nuclei and associated structures, can integrate neural, endocrine, metabolic, and immune information and plays a pivotal role in the development and functions of the immune system. The OSS can promote the development of thymus and bone marrow, perform immune surveillance, strengthen immune defense, and maintain immune homeostasis. Correspondingly, OT can inhibit inflammation, exert antibiotic-like effect, promote wound healing and regeneration, and suppress stress-associated immune disorders. In this process, the OSS can release OT to act on immune system directly by activating OT receptors or through modulating activities of other hypothalamic–pituitary–immune axes and autonomic nervous system indirectly. However, our understandings of the role of the OSS in neuroendocrine regulation of immune system are largely incomplete, particularly its relationship with other hypothalamic–pituitary–immune axes and the vasopressin-secreting system that coexists with the OSS in the HNS. In addition, it remains unclear about the relationship between the OSS and peripherally produced OT in immune regulation, particularly intrathymic OT that is known to elicit central immunological self-tolerance of T-cells to hypophysial hormones. In this work, we provide a brief review of current knowledge of the features of OSS regulation of the immune system and of potential approaches that mediate OSS coordination of the activities of entire neuroendocrine–immune network.

Uric Acid Crystals Induce Placental Inflammation and Alter Trophoblast Function via an IL-1-Dependent Pathway: Implications for Fetal Growth Restriction

Excessive placental inflammation is associated with several pathological conditions, including stillbirth and fetal growth restriction. Although infection is a known cause of inflammation, a significant proportion of pregnancies have evidence of inflammation without any detectable infection. Inflammation can also be triggered by endogenous mediators, called damage associated molecular patterns or alarmins. One of these damage-associated molecular patterns, uric acid, is increased in the maternal circulation in pathological pregnancies and is a known agonist of the Nlrp3 inflammasome and inducer of inflammation. However, its effects within the placenta and on pregnancy outcomes remain largely unknown. We found that uric acid (monosodium urate [MSU]) crystals induce a proinflammatory profile in isolated human term cytotrophoblast cells, with a predominant secretion of IL-1β and IL-6, a result confirmed in human term placental explants. The proinflammatory effects of MSU crystals were shown to be IL-1-dependent using a caspase-1 inhibitor (inhibits IL-1 maturation) and IL-1Ra (inhibits IL-1 signaling). The proinflammatory effect of MSU crystals was accompanied by trophoblast apoptosis and decreased syncytialization. Correspondingly, administration of MSU crystals to rats during late gestation induced placental inflammation and was associated with fetal growth restriction. These results make a strong case for an active proinflammatory role of MSU crystals at the maternal-fetal interface in pathological pregnancies, and highlight a key mediating role of IL-1. Furthermore, our study describes a novel in vivo animal model of noninfectious inflammation during pregnancy, which is triggered by MSU crystals and leads to reduced fetal growth.

Histological chorioamnionitis in preterm prelabor rupture of the membranes is associated with increased expression of galectin-3 by amniotic epithelium

PURPOSE

Gal-3, which can regulate immune responses upon infection and inflammation, was not studied so far in intrauterine infection leading to preterm prelabor rupture of the membranes (PPROM), although gal-1 was reported to be implicated in the process. Gal-3 mRNA and protein expression in amnion and its changes during histological chorioamnionitis were studied here.

MATERIALS AND METHODS

Fetal membranes were obtained from women with PPROM with (n =15) and without histological chorioamnionitis (n =15) during second and third trimester. Immunohistochemical reactivity was evaluated semiquantitatively and analyzed using t-test. Galectin profile of amniotic epithelia was determined by polymerase chain reaction (PCR) and change assessed in gal-3 in PPROM with (n =5) or without histological chorioamnionitis (n =5) by real-time PCR.

RESULTS

Human amniotic epithelium was found to express gal-1, gal-3, gal-7 and gal-8 mRNA. Gal-3 mRNA and protein is increased in fetal membranes and in the amniotic epithelium in patients with chorionamnionitis.

CONCLUSION

Histological chorioamnionitis is associated with increased gal-3 expression and strong immunoreactivity of the amnion. Gal-3 may participate in the regulation of the inflammatory responses to chorioamniotic infection and/or direct interaction with pathogens.

The Role of Matrix Degrading Enzymes and Apoptosis in Repture of Membranes

Prematurity is the third leading cause of perinatal death, and preterm premature rupture of the membranes (pPROM) is associated with approximately 20-50% of all preterm births. The etiologic factors described for pPROM and preterm labor (PTL) are the same, although the clinical presentation (pPROM vs PTL) differs among patients. The reason for this disparity is unknown and poses a therapeutic dilemma. Several etiologic factors have been described for PTL and pPROM. PTL and pPROM are associated with overwhelming host inflammatory response. Many of these pro-inflammatory factors (inflammatory cytokine release) are common in both conditions; however, the clinical presentation differs. The objective of this review is to explain the differential expression pattern of matrix metalloproteinases (MMPs) and pro-apoptotic elements in human fetal membranes in pPROM and PTL and how they interact to present different clinical outcomes during pregnancy.

Comparative Analysis of Midtrimester Amniotic Fluid Cytokine Levels to Predict Spontaneous Very Pre-term Birth in Patients with Cervical Insufficiency

PROBLEM

Few studies have investigated the roles of cytokines and chemokines in women with cervical insufficiency, and those that have done so evaluated only a limited number of cytokines in amniotic fluid.

METHOD OF STUDY

A retrospective cohort study enrolled 71 patients undergoing physical examination-indicated cerclage to determine whether expanded amniotic fluid cytokine levels predict spontaneous very pre-term birth (≤32 weeks of gestation) in patients with cervical insufficiency. Analysis of multiple cytokines and chemokines was performed with the multiplex immunoassay.

RESULTS

Sixty-seven amniotic fluid samples were available for analysis and assayed for 15 cytokines. Thirty-eight (56.7%) patients delivered pre-term. Of these, 26 (38.8%) were spontaneous very pre-term births. Most cytokine levels were significantly increased in the amniotic fluid from the study group when compared with those from controls. The levels of interleukin-1β (IL-1β), IL- 6, IL- 7, IL-15, IL-17α, tumour necrosis factor-α (TNF-α), MIP-1α, and MIP-1β were higher in patients with a very pre-term delivery than in those with a late pre-term delivery. IL-1β, IL-6, IL-7, IL-17α, TNF-α, and cervical dilation were independently associated with a very pre-term birth.

CONCLUSION

Intra-amniotic inflammation may contribute to cervical insufficiency, and the severity of inflammation is associated with a very pre-term birth in women with cervical insufficiency.

Oxytocin-secreting system: A major part of the neuroendocrine center regulating immunologic activity

Interactions between the nervous system and immune system have been studied extensively. However, the mechanisms underlying the neural regulation of immune activity, particularly the neuroendocrine regulation of immunologic functions, remain elusive. In this review, we provide a comprehensive examination of current evidence on interactions between the immune system and hypothalamic oxytocin-secreting system. We highlight the fact that oxytocin may have significant effects in the body, beyond its classical functions in lactation and parturition. Similar to the hypothalamo-pituitary-adrenal axis, the oxytocin-secreting system closely interacts with classical immune system, integrating both neurochemical and immunologic signals in the central nervous system and in turn affects immunologic defense, homeostasis, and surveillance. Lastly, this review explores therapeutic potentials of oxytocin in treating immunologic disorders.

Do the levels of tumor makers or proinflammatory cytokines in mid-trimester cervical fluid predict early-stage cervical shortening?

AIM

In the present study, we aimed to assess the biomarkers in mid-trimester cervical fluid that can predict early stage cervical shortening.

MATERIAL AND METHODS

We obtained cervical swab specimens from 96 gravidas, after which the cervical length was measured, at approximately 20 weeks of gestation. Cervical length was measured again at 4 weeks after the initial examination. Cervical shortening was noted in 20 women between 20 and 24 weeks of gestation (group A), whereas no cervical shortening was noted in 76 women (group B). We evaluated the use of the levels of tumor markers, proinflammatory cytokines, and matrix metalloproteinase-8 (MMP-8) as candidate biomarkers. CA-125 and carcinoembryonic antigen levels were determined by using an automatic immunoassay system in both groups. Furthermore, IL-1β, IL-8, tumor necrosis factor-α, and MMP-8 levels were measured using an enzyme-linked immunosorbent assay.

RESULTS

The levels of inflammatory cytokines and MMP-8 did not differ between the two groups, and were not correlated with cervical length or the change in cervical length. Although CA-125 and carcinoembryonic antigen levels were higher in group A, they were not statistically significant (P = 0.304 and 0.092, respectively).

CONCLUSION

Early stage cervical shortening in mid-trimester was not associated with an increase in the levels of tumor markers or proinflammatory cytokines in cervical fluid.

Mechanisms of chorioamnionitis-associated preterm birth: interleukin-1β inhibits progesterone receptor expression in decidual cells

In chorioamnionitis (CAM), a major cause of preterm birth (PTB), maternal-fetal inflammation of the decidua and amniochorion cause the release of cytokines that elicit cervical ripening, fetal membrane rupture and myometrial activation. We posit that this inflammatory milieu triggers PTB by inhibiting progesterone receptor (PR) expression and increasing decidual prostaglandin (PG) production. Immunohistochemical staining of decidua detected significantly lower PR levels in decidual cells (DCs) from CAM-complicated PTB. Incubation of DCs with IL-1β decreased PR expression and significantly increased PGE2 and PGF2α production and COX-2 expression. The addition of PGF2α to DC cultures also suppressed PR expression. However, the COX inhibitor, indomethacin, did not reverse IL-1β suppression of PR expression in DC cultures. Although IL-1β treatment activated the NF-KB, ERK1/2 and p38 MAPK signalling cascades in DCs, inhibition of ERK1/2 MAPK signalling alone was sufficient to completely reverse the suppression of PR levels by IL-1β. These findings suggest that CAM-associated PTB is induced at least in part by IL-1β-mediated functional progesterone withdrawal.

Amniotic fluid CA-125 as a marker of intra-amniotic inflammation associated with preterm delivery: a preliminary single center study

OBJECTIVE

The purpose of this study was to investigate whether amniotic fluid (AF) CA-125 in patients with preterm labor or preterm premature rupture of membranes can help predict intra-amniotic inflammation (IAI), microbial invasion of the amniotic cavity (MIAC) and imminent delivery.

METHODS

We recruited 36 women who admitted with impending preterm delivery and suspicious AF infection. AF matrix metalloproteinase-8 (MMP-8), white blood cell (WBC) count, glucose levels, and CA-125 levels were measured, and the MMP-8 bedside rapid test was also performed. AF culture and PCR were subsequently performed to confirm MIAC. We compared AF CA-125 levels according to the presence of IAI or MIAC and assessed its predictive value for delivery within 7 days of admission.

RESULTS

AF CA-125 levels were significantly higher in the IAI group than in the non-IAI group (mean ± standard deviation: 5608 ± 864 vs 904 ± 84 IU/ml; p = 0.001). AF CA-125 levels showed a negative correlation with gestational age and a positive correlation with AF WBC counts and MMP-8 levels. AF CA-125 levels were higher in the MIAC group, though this difference was not statistically significant (p = 0.064). Delivery within 7 days of admission was significantly more common in patients with higher AF CA-125 levels (cut-off: 1650 IU/ml, sensitivity: 71.4 %, specificity: 86.4 %, p = 0.005).

CONCLUSION

AF CA-125 levels are increased in patients with AF inflammation and can be a predictor of imminent preterm delivery.

Salmonella enterica serovar Enteritidis enterocolitis during late stages of gestation induces an adverse pregnancy outcome in the murine model

Foodborne diseases caused by Salmonella enterica serovar Enteritidis (S. Enteritidis) are a significant health problem. Pregnancy, state of immunological tolerance, is a predisposing condition for the development of infections with intracellular pathogens. Salmonella species can cause pregnancy complications such as chorioamnionitis, transplacental fetal infection, pre term labor, abortions, neonatal and maternal septicemia. However, the specific mechanisms by which Salmonella infections trigger these alterations are not clear. In the present work, using a self-limiting enterocolitis murine model, we show that the ingestion of a low dose of S. Enteritidis at late stages of pregnancy (day 15 of gestation) is sufficient to induce massive maternal infection. We found that Salmonella infection leads to 40% of pre term delivery, 33% of abortion and fetal growth restriction. Placental dysfunction during S. Enteritidis enterocolitis was confirmed through cellular infiltration and hypoxia markers (MPO activity and COX-1 and COX-2 expression, respectively). Apoptosis in placental tissue due to Salmonella infection was also evident at day 18 of gestation when investigated by morphometric procedure, DNA fragmentation and Fas/FasL expression. Also, the expression of IFN-γ, TNF-α, IL-17 and IL-10 was up regulated in response to Salmonella not only in placenta, but also in amniotic fluid and maternal serum. Altogether, our results demonstrate that S. Enteritidis enterocolitis during late stages of gestation causes detrimental effect on pregnancy outcome.

Circulating cytokines and alarmins associated with placental inflammation in high-risk pregnancies

Problem

Inflammation during pregnancy has devastating consequences for the placenta and fetus. These events are incompletely understood, thereby hampering screening and treatment.

Method of study

The inflammatory profile of villous tissue was studied in pregnancies at high-risk of placental dysfunction and compared to uncomplicated pregnancies. The systemic inflammatory profile was assessed in matched maternal serum samples in cases of reduced fetal movements (RFM).

Results

Placentas from RFM pregnancies had a unique inflammatory profile characterized by increased interleukin (IL)-1 receptor antagonist and decreased IL-10 expression, concomitant with increased numbers of placental macrophages. This aberrant cytokine profile was evident in maternal serum in RFM, as were increased levels of alarmins (uric acid, HMGB1, cell-free fetal DNA).

Conclusion

This distinct inflammatory profile at the maternal-fetal interface, mirrored in maternal serum, could represent biomarkers of placental inflammation and could offer novel therapeutic options to protect the placenta and fetus from an adverse maternal environment.

Role of immunological factors in the pathophysiology and diagnosis of bipolar disorder: comparison with schizophrenia

Several lines of evidence point to the key role of neurobiological mechanisms and shared genetic background in schizophrenia and bipolar disorder. For both disorders, neurodevelopmental and neurodegenerative processes have been postulated to be relevant for the pathogenesis as well as dysregulation of immuno-inflammatory pathways. Inflammation is a complex biological response to harmful stimuli and it is mediated by cytokines cascades, cellular immune responses, oxidative factors and hormone regulation. Cytokines, in particular, are supposed to play a critical role in infectious and inflammatory processes, mediating the cross-talk between the brain and the immune system; they also possibly contribute to the development of the central nervous system. From this perspective, even though mixed results have been reported, it seems that both schizophrenia and bipolar disorder are associated with an imbalance in inflammatory cytokines; in fact, some of these could represent biological markers of illness and could be possible targets for pharmacological treatments. In light of these considerations, the purpose of the present paper was to provide a comprehensive and critical review of the existing literature about immunological abnormalities in bipolar disorder with particular attention to the similarities and differences with schizophrenia.

Targeting interleukin-6 receptor inhibits preterm delivery induced by inflammation

Intrauterine infection is still a common trigger of preterm delivery (PTD) and also a determinant risk factor for the subsequent development of neurodevelopmental abnormalities in neonates. In this study, we examined the expressional pattern of various inflammatory cytokines such as interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) in placentae complicated with severe chorioamnionitis (CAM) and found that IL-6 is mainly expressed in macrophages in villous mesenchyme by immunohistochemical analysis with anti-CD-68 antibody. Using an experimental lipopolysaccharide (LPS)-induced PTD model, the therapeutic potential of targeting this cytokine was investigated. Anti-IL-6 receptor antibody (MR16-1) was delivered 6 h before LPS treatment. Mice in the MR16-1 group had a significantly lower rate of PTD (17%) than in the controls (53%, P = 0.026). As a result, MR16-1 treatment significantly prolonged the gestational period (control; 18.4 ± 1.7d, MR16-1; 19.8 ± 1.5d, P = 0.007) without any apparent adverse events on the mice and their pups. In primary human amniotic epithelial cells, pretreatment with a humanized anti-human IL-6 receptor antibody, tocilizumab, significantly inhibited the production of prostaglandin E2 induced by IL-6. In conclusion, IL-6 was strongly expressed mainly in macrophages in villous mesenchyme in placentae complicated with CAM. Anti-IL-6R antibody significantly decreased the rate of PTD in LPS-induced inflammatory model in mice, and inhibited PGE2 production from human primary amniotic epithelial cells. Targeting IL-6 signaling could be a promising option for the prevention of PTD and needs to be further explored for future clinical application.

Lipopolysaccharide disrupts the milk-blood barrier by modulating claudins in mammary alveolar tight junctions

Mastitis, inflammation of the mammary gland, is the most costly common disease in the dairy industry, and is caused by mammary pathogenic bacteria, including Escherichia coli. The bacteria invade the mammary alveolar lumen and disrupt the blood-milk barrier. In normal mammary gland, alveolar epithelial tight junctions (TJs) contribute the blood-milk barrier of alveolar epithelium by blocking the leakage of milk components from the luminal side into the blood serum. In this study, we focused on claudin subtypes that participate in the alveolar epithelial TJs, because the composition of claudins is an important factor that affects TJ permeability. In normal mouse lactating mammary glands, alveolar TJs consist of claudin-3 without claudin-1, -4, and -7. In lipopolysaccharide (LPS)-induced mastitis, alveolar TJs showed 2-staged compositional changes in claudins. First, a qualitative change in claudin-3, presumably caused by phosphorylation and participation of claudin-7 in alveolar TJs, was recognized in parallel with the leakage of fluorescein isothiocyanate-conjugated albumin (FITC-albumin) via the alveolar epithelium. Second, claudin-4 participated in alveolar TJs with claudin-3 and claudin-7 12 h after LPS injection. The partial localization of claudin-1 was also observed by immunostaining. Coinciding with the second change of alveolar TJs, the severe disruption of the blood-milk barrier was recognized by ectopic localization of β-casein and much leakage of FITC-albumin. Furthermore, the localization of toll-like receptor 4 (TLR4) on the luminal side and NFκB activation by LPS was observed in the alveolar epithelial cells. We suggest that the weakening and disruption of the blood-milk barrier are caused by compositional changes of claudins in alveolar epithelial TJs through LPS/TLR4 signaling.

Neurodevelopment and inflammatory patterns in schizophrenia in relation to pathophysiology

As for other major psychoses, the etiology of schizophrenia still remains poorly understood, involving genetic and epigenetic mechanisms, as well as environmental contributions. In addition, immune alterations have been widely reported in schizophrenic patients, involving both the unspecific and specific pathways of the immune system, and suggesting that infectious/autoimmune processes play an important role in the etiopathogenesis of the disorder. Cytokines, in particular, are supposed to play a critical role in infectious and inflammatory processes, mediating the cross-talk between the brain and the immune system. In this perspective, even though mixed results have been reported, it seems that schizophrenia is associated with an imbalance in inflammatory cytokines. Alterations in the inflammatory and immune systems, moreover, seem to be already present in the early stages of schizophrenia and connected to the neurodevelopmental hypothesis of the disorder, identifying its roots in brain development abnormalities that do not manifest themselves until adolescence or early adulthood. At the same time, neuropathological and longitudinal studies in schizophrenia also support a neurodegenerative hypothesis and, more recently, a novel mixed hypothesis, integrating neurodevelopmental and neurodegenerative models, has been put forward. The present review aims to provide an updated overview of the connections between the immune and inflammatory alterations and the aforementioned hypotheses in schizophrenia.