Possible early prediction of preterm birth by determination of novel proinflammatory factors in midtrimester amniotic fluid

Intra-amniotic inflammation in the mid-trimester of pregnancy is a risk factor for neuropsychological disorders in childhood

OBJECTIVES

Intra-amniotic inflammation is a subclinical condition frequently caused by either microbial invasion of the amniotic cavity or sterile inflammatory stimuli, e.g., alarmins. An accumulating body of evidence supports a role for maternal immune activation in the genesis of fetal neuroinflammation and the occurrence of neurodevelopmental disorders such as cerebral palsy, schizophrenia, and autism. The objective of this study was to determine whether fetal exposure to mid-trimester intra-amniotic inflammation is associated with neurodevelopmental disorders in children eight to 12 years of age.

METHODS

This is a retrospective case-control study comprising 20 children with evidence of prenatal exposure to intra-amniotic inflammation in the mid-trimester and 20 controls matched for gestational age at amniocentesis and at delivery. Amniotic fluid samples were tested for concentrations of interleukin-6 and C-X-C motif chemokine ligand 10, for bacteria by culture and molecular microbiologic methods as well as by polymerase chain reaction for eight viruses. Neuropsychological testing of children, performed by two experienced psychologists, assessed cognitive and behavioral domains. Neuropsychological dysfunction was defined as the presence of an abnormal score (<2 standard deviations) on at least two cognitive tasks.

RESULTS

Neuropsychological dysfunction was present in 45% (9/20) of children exposed to intra-amniotic inflammation but in only 10% (2/20) of those in the control group (p=0.03). The relative risk (RR) of neuropsychological dysfunction conferred by amniotic fluid inflammation remained significant after adjusting for gestational age at delivery [aRR=4.5 (1.07-16.7)]. Of the 11 children diagnosed with neuropsychological dysfunction, nine were delivered at term and eight of them had mothers with intra-amniotic inflammation. Children exposed to intra-amniotic inflammation were found to have abnormalities in neuropsychological tasks evaluating complex skills, e.g., auditory attention, executive functions, and social skills, whereas the domains of reasoning, language, and memory were not affected in the cases and controls.

CONCLUSIONS

Asymptomatic sterile intra-amniotic inflammation in the mid-trimester of pregnancy, followed by a term birth, can still confer to the offspring a substantial risk for neurodevelopmental disorders in childhood. Early recognition and treatment of maternal immune activation in pregnancy may be a strategy for the prevention of subsequent neurodevelopmental disorders in offspring.

Insights Into the Regulation of Gynecological Inflammation-Mediated Malignancy by Metalloproteinases

Gynecological illness accounts for around 4.5% of the global disease burden, which is higher than other key global health concerns such as malaria (1.04%), TB (1.9%), ischemic heart disease (2.2%), and maternal disorders (3.5%). Gynecological conditions in women of reproductive age are linked to both in terms of diagnosis and treatment, especially in low-income economies, which poses a serious social problem. A greater understanding of health promotion and illness management can help to prevent diseases in gynecology. Due to the lack of established biomarkers, the identification of gynecological diseases, including malignancies, has proven to be challenging in most situations, and histological exams remain the gold standard. Metalloproteinases (MMPs, ADAMs, ADAMTSs) and their endogenous inhibitors (TIMPs) modulate the protease-dependent bioavailability of local niche components (e.g., growth factors), matrix turnover, and cellular interactions to govern specific physical and biochemical characteristics of the environment. Matrix metalloproteinases (MMPs), A Disintegrin and Metalloproteinase (ADAM), and A Disintegrin and Metalloproteinase with Thrombospondin Motif (ADAMTS) are zinc-dependent endopeptidases that contribute significantly to the disintegration of extracellular matrix proteins and shedding of membrane-bound receptor molecules in several diseases, including arthritis. MMPs are noteworthy genes associated with cancer development, functional angiogenesis, invasion, metastasis, and immune surveillance evasion. These genes are often elevated in cancer and multiple benign gynecological disorders like endometriosis, according to research. Migration through the extracellular matrix, which involves proteolytic activity, is an essential step in tumor cell extravasation and metastasis. However, none of the MMPs’ expression patterns, as well as their diagnostic and prognostic potential, have been studied in a pan-cancer context. The latter plays a very important role in cell signaling and might be used as a cancer treatment target. ADAMs are implicated in tumor cell proliferation, angiogenesis, and metastasis. This review will focus on the contribution of the aforementioned metalloproteinases in regulating gynecological disorders and their subsequent manipulation for therapeutic intervention.

A Systematic Review of Bisphenol A from Dietary and Non-Dietary Sources during Pregnancy and Its Possible Connection with Fetal Growth Restriction: Investigating Its Potential Effects and the Window of Fetal Vulnerability

Bisphenol A (BPA), a ubiquitous endocrine-disrupting chemical (EDC), is increasingly hypothesized to be a factor contributing to changes in fetal growth velocity. BPA exposure may be environmental, occupational, and/or dietary, with canned foods and plastic bottles contributing significantly. Our systematic review aims to evaluate the current literature and to investigate the role of BPA in abnormal fetal growth patterns. A search was conducted in the PubMed and Cochrane databases. A total of 25 articles met the eligibility criteria and were included in this systematic review. Eleven of them failed to show a clear relationship between BPA and abnormal fetal growth. The majority of the remaining studies (9/14) found an inverse association of BPA with indicators of fetal growth, whereas three studies suggested increased fetal growth, and two studies produced contradictory findings. Of note, both of the studies that collected a sample (amniotic fluid) directly reflecting BPA concentration in the fetus during the first half of pregnancy revealed an inverse association with birth weight. In conclusion, there is mounting evidence that combined exposure to BPA from dietary and non-dietary sources during pregnancy may contribute to abnormal fetal growth; a tendency towards fetal growth restriction was shown, especially when exposure occurs during the first half.

Perinatal Inflammation: Could Partial Blocking of Cell Adhesion Molecule Function Be a Solution?

In spite of the great advances made in recent years in prenatal and perinatal medicine, inflammation can still frequently result in injury to vital organs and often constitutes a major cause of morbidity. It is today well established that in neonates—though vulnerability to infection among neonates is triggered by functional impairments in leukocyte adhesion—the decreased expression of cell adhesion molecules also decreases the inflammatory response. It is also clear that the cell adhesion molecules, namely, the integrins, selectins, and the immunoglobulin (Ig) gene super family, all play a crucial role in the inflammatory cascade. Thus, by consolidating our knowledge concerning the actions of these vital cell adhesion molecules during the prenatal period as well as regarding the genetic deficiencies of these molecules, notably leukocyte adhesion deficiency (LAD) I, II, and III, which can provoke severe clinical symptoms throughout the first year of life, it is anticipated that intervention involving blocking the function of cell adhesion molecules in neonatal leukocytes has the potential to constitute an effective therapeutic approach for inflammation. A promising perspective is the potential use of antibody therapy in preterm and term infants with perinatal inflammation and infection focusing on cases in which LAD is involved, while a further important scientific advance related to this issue could be the combination of small peptides aimed at the inhibition of cellular adhesion.

Identifying the potential protein biomarkers of preterm birth in amniotic fluid

OBJECTIVE

Preterm birth severely threatens neonatal health and life. Although the detailed mechanism of preterm birth is not well understood, accurately predicting preterm birth can help people make preparations in advance, greatly reducing the subsequent health risk of neonates. Therefore, in this study, we aimed to identify potential protein biomarkers of preterm birth in amniotic fluid (AF).

MATERIALS AND METHODS

We first enrolled pregnant subjects and collected their AF samples when they underwent amniocentesis at the second trimester of gestation. After delivery, the collected AF samples were classified into a full-term birth (sample size n = 21) set or preterm birth (n = 36) set, followed by 2-D DIGE and MS/MS assays.

RESULTS

By doing so, we identified seven potential protein biomarkers of preterm birth, three of which were further validated in all samples with ELISA, including Apolipoprotein A-IV (Apoa4), Lumican (Lum) and Kininogen-1 (Kng1). As a result, all three potential biomarkers were significantly differently expressed between preterm and full-term birth AF samples. Furthermore, without prior classification, we found that these three biomarkers were positively correlated with gestation age (correlation coefficient ranging from 0.25 to 0.38) and were able to predict the occurrence of preterm birth.

CONCLUSION

In this study, by examining amniotic fluid, we identified three biomarker proteins that may facilitate the identification of preterm birth. There three proteins were never reported to be related to preterm birth. Their pathogenesis roles in preterm birth deserve further investigations by using in vitro cell model or in vivo animal model assays.

The impact of trophic and immunomodulatory factors on oligodendrocyte maturation: Potential treatments for encephalopathy of prematurity

Encephalopathy of prematurity (EoP) is a major cause of morbidity in preterm neonates, causing neurodevelopmental adversities that can lead to lifelong impairments. Preterm birth-related insults, such as cerebral oxygen fluctuations and perinatal inflammation, are believed to negatively impact brain development, leading to a range of brain abnormalities. Diffuse white matter injury is a major hallmark of EoP and characterized by widespread hypomyelination, the result of disturbances in oligodendrocyte lineage development. At present, there are no treatment options available, despite the enormous burden of EoP on patients, their families, and society. Over the years, research in the field of neonatal brain injury and other white matter pathologies has led to the identification of several promising trophic factors and cytokines that contribute to the survival and maturation of oligodendrocytes, and/or dampening neuroinflammation. In this review, we discuss the current literature on selected factors and their therapeutic potential to combat EoP, covering a wide range of in vitro, preclinical and clinical studies. Furthermore, we offer a future perspective on the translatability of these factors into clinical practice.

Comparative analysis of gingival crevicular fluid a disintegrin and metalloproteinase 8 levels in health and periodontal disease: A clinic-biochemical study

AIM AND BACKGROUND

A disintegrin and metalloproteinase 8 (ADAM8) is a marker belonging to the class of ADAM family of metalloproteinase which is found to be involved in inflammation and bone resorption in periodontal disease by acting as osteoclast stimulating factor. In several systemic inflammatory diseases, elevated levels of ADAM8 are detected in human serum and other body fluids. Recently, ADAM8 was even detected in gingival crevicular fluid (GCF) of patients with periodontal diseases. Hence, the aim of the study was to estimate the levels of ADAM8 in GCF of healthy and chronic periodontitis subjects.

MATERIALS AND METHODS

Periodontal examination and collection of GCF by the extracrevicular method was performed in 30 subjects selected randomly and categorized into two groups. Group I (healthy, n = 15) and Group II (chronic periodontitis, n = 15). ADAM8 levels in GCF were estimated by enzyme-linked immunosorbent assay.

RESULTS

ADAM8 was detected in both Group I and II. Highest mean ADAM8 concentration was obtained for Group II, whereas the lowest concentration was seen in Group I. This suggests that ADAM8 levels increase proportionally with the progression of periodontal disease. There was a significant correlation between ADAM8 levels and clinical parameters in the study group.

CONCLUSION

The results of our study indicate that the ADAM8 levels in GCF are positively associated with periodontal disease, which may provide a useful tool in monitoring its progression. Nevertheless, further longitudinal studies are required with larger sample sizes in which ADAM8 levels are progressively estimated and compared to baseline values.

Predicting Preterm Labour: Current Status and Future Prospects

Preterm labour and birth are a major cause of perinatal morbidity and mortality. Despite modern advances in obstetric and neonatal management, the rate of preterm birth in the developed world is increasing. Yet even though numerous risk factors associated with preterm birth have been identified, the ability to accurately predict when labour will occur remains elusive, whether it is at a term or preterm gestation. In the latter case, this is likely due to the multifactorial aetiology of preterm labour wherein women may display different clinical presentations that lead to preterm birth. The discovery of novel biomarkers that could reliably identify women who will subsequently deliver preterm may allow for timely medical intervention and targeted therapeutic treatments aimed at improving maternal and fetal outcomes. Various body fluids including amniotic fluid, urine, saliva, blood (serum/plasma), and cervicovaginal fluid all provide a rich protein source of putative biochemical markers that may be causative or reflective of the various pathophysiological disorders of pregnancy, including preterm labour. This short review will highlight recent advances in the field of biomarker discovery and the utility of single and multiple biomarkers for the prediction of preterm birth in the absence of intra-amniotic infection.

The integrative roles of chemokines at the maternal-fetal interface in early pregnancy

Embryos express paternal antigens that are foreign to the mother, but the mother provides a special immune milieu at the fetal-maternal interface to permit rather than reject the embryo growth in the uterus until parturition by establishing precise crosstalk between the mother and the fetus. There are unanswered questions in the maintenance of pregnancy, including the poorly understood phenomenon of maternal tolerance to the allogeneic conceptus, and the remarkable biological roles of placental trophoblasts that invade the uterine wall. Chemokines are multifunctional molecules initially described as having a role in leukocyte trafficking and later found to participate in developmental processes such as differentiation and directed migration. It is increasingly evident that the gestational uterine microenvironment is characterized, at least in part, by the differential expression and secretion of chemokines that induce selective trafficking of leukocyte subsets to the maternal-fetal interface and regulate multiple events that are closely associated with normal pregnancy. Here, we review the expression and function of chemokines and their receptors at the maternal-fetal interface, with a special focus on chemokine as a key component in trophoblast invasiveness and placental angiogenesis, recruitment and instruction of immune cells so as to form a fetus-supporting milieu during pregnancy. The chemokine network is also involved in pregnancy complications.

Th2-like chemokine levels are increased in allergic children and influenced by maternal immunity during pregnancy

BACKGROUND

The influence of the intra-uterine environment on the immunity and allergy development in the offspring is unclear. We aimed to investigate (i) whether the pregnancy magnifies the Th2 immunity in allergic and non-allergic women, (ii) whether the maternal chemokine levels during pregnancy influenced the offspring's chemokine levels during childhood and (iii) the relationship between circulating Th1/Th2-associated chemokines and allergy in mothers and children.

METHODS

The Th1-associated chemokines CXCL9, CXCL10, CXCL11, and the Th2-associated chemokines CCL17, CCL18 and CCL22 were quantified by Luminex and ELISA in 20 women with and 36 women without allergic symptoms at gestational week (gw) 10-12, 15-16, 25, 35, 39 and 2 and 12 months post-partum and in their children at birth, 6, 12, 24 months and 6 years of age. Total IgE levels were measured using ImmunoCAP Technology.

RESULTS

The levels of the Th2-like chemokines were not magnified by pregnancy. Instead decreased levels were shown during pregnancy (irrespectively of maternal allergy status) as compared to post-partum. In the whole group, the Th1-like chemokine levels were higher at gw 39 than during the first and second trimester and post-partum. Maternal CXCL11, CCL18 and CCL22 levels during and after pregnancy correlated with the corresponding chemokines in the offspring during childhood. Increased CCL22 and decreased CXCL10 levels in the children were associated with sensitisation and increased CCL17 levels with allergic symptoms during childhood. Maternal chemokine levels were not associated with maternal allergic disease.

CONCLUSIONS

Allergic symptoms and sensitisation were associated with decreased Th1- and increased Th2-associated chemokine levels during childhood, indicating a Th2 shift in the allergic children, possibly influenced by the maternal immunity during pregnancy.

Chemokines profiling of patients with preterm birth

Introduction. Nowadays it is thought that the main cause of premature birth is subclinical infection. However, none of the currently used methods provide effective prevention to preterm labor. The aim of the study was to determine the concentration of selected chemokines in sera of patients with premature birth without clinical signs of infection (n = 62), threatened preterm labor (n = 47), and term births (n = 28). Method. To assess the concentration of chemokines in the blood serum, we used a multiplex method, which allows the simultaneous determination of 40 chemokines per sample. The sets consist of the following chemokines: 6Ckine/CCL21, Axl, BTC, CCL28, CTACK/CCL27, CXCL16, ENA-78/CXCL5, Eotaxin-3/CCL26, GCP-2/CXC, GRO (GROα/CXCL1, GROβ/CXCL2 and GROγ/CXCL3), HCC-1/CCL14, HCC-4/CCL16, IL-9, IL-17F, IL18-BPa, IL-28A, IL-29, IL-31, IP-10/CXCL10, I-TAC/CXCL11, LIF, LIGHT/TNFSF14, Lymphotactin/XCL1, MCP-2/CCL8, MCP-3/CCL7, MCP-4/CCL13, MDC/CCL22, MIF, MIP-3α/CCL20, MIP-3-β/CCL19, MPIF-1/CCL23, NAP-2/CXCL7, MSPα, OPN, PARC/CCL18, PF4, SDF-1/CXCL12, TARC/CCL17, TECK/CCL25, and TSLP. Results. We showed possible implication of 4 chemokines, that is, HCC-4, I-TAC, MIP-3α, and TARC in women with symptoms of preterm delivery. Conclusion. On the basis of our findings, it seems that the chemokines may play role in the pathogenesis of preterm labor. Defining their potential as biochemical markers of preterm birth requires further investigation on larger group of patients.

Amniotic fluid urocortin-1 concentrations for the prediction of preterm delivery

AIM

The aim of this study was to analyze whether urocortin-1 concentration in midtrimester amniotic fluid could serve as an indicative marker of preterm labor.

MATERIAL AND METHODS

A retrospective cohort study was conducted. Urocortin-1 concentrations in midtrimester amniotic fluid were measured in 22 pregnant women with preterm deliveries and 45 women who delivered at term using enzyme-linked immunosorbent assay.

RESULTS

The median amniotic fluid urocortin-1 concentration was significantly lower in the women with preterm birth (40.06 pg/mL; range, 13.77-67.58 pg/mL) than in the women who gave birth at term (49.56 pg/mL; range, 26.25-175.9 pg/mL; P = 0.022). The result of receiver-operator curve analysis indicates that an amniotic fluid urocortin-1 concentration ≤ 57.88 pg/mL had an area under the curve of 0.673 (95% confidence interval, 0.55-0.78; P = 0.01) with a sensitivity of 81.8%, specificity of 40.0%, positive predictive value of 40%, and a negative predictive value of 82% in identifying which of the patients subsequently delivered prematurely.

CONCLUSIONS

These results suggest that low urocortin-1 concentration in midtrimester amniotic fluid could be used as an indicative marker of preterm birth.

Acute lung injury in preterm fetuses and neonates: mechanisms and molecular pathways

Acute lung injury (ALI) results in high morbidity and mortality among preterm neonates and efforts have therefore been devoted to both antenatal and postnatal prevention of the disease. ALI is the result of an inflammatory response which is triggered by a variety of different mechanisms. It mostly affects the fetal lung and, in particular, causes damage to the integrity of the lung's alveolar-capillary unit while weakening its cellular linings. Chemotactic activity and inflammatory products, such as proinflammatory cytokines TNF-α, IL-1, IL-6, IL-11, VEGF,TGF-α and TGF-β, provoke serious damage to the capillary endothelium and the alveolar epithelium, resulting in hyaline membrane formation and leakage of protein-rich edema fluid into the alveoli. Chorioamnionitis plays a major part in triggering fetal lung inflammation, while mechanical ventilation, the application of which is frequently necessary in preterm neonates, also causes ALI by inducing proinflammatory cytokines. Many different ventilation-strategies have been developed in order to reduce potential lung injury. Furthermore, tissue injury may occur as a result of injurious oxygen by-products (Reactive Oxygen Species, ROS), secondary to hyperoxia. Knowledge of the inflammatory pathways that connect intra-amniotic inflammation and ALI can lead to the formulation of novel interventional procedures. Future research should concentrate on the pathophysiology of ALI in preterm neonates and οn possible pharmaceutical interventions targeting prevention and/or resolution of ALI.

Midtrimester amniotic fluid concentrations of interleukin-6 and interferon-gamma-inducible protein-10: evidence for heterogeneity of intra-amniotic inflammation and associations with spontaneous early (<32 weeks) and late (>32 weeks) preterm delivery

INTRODUCTION

Intra-amniotic inflammation is traditionally defined as an elevation of amniotic fluid interleukin (IL)-6. Previous case control studies have suggested an association between an elevated midtrimester amniotic fluid IL-6 and preterm delivery, although such an association has been recently challenged. Intra-amniotic inflammation can also be defined by an elevation of the T-cell chemokine, Interferon-gamma-inducible protein (IP)-10. An elevation in amniotic fluid IP-10 has been associated with chronic chorioamnionitis, a lesion frequently found in late spontaneous preterm birth and fetal death. In contrast, an elevation in amniotic fluid IL-6 is typically associated with acute chorioamnionitis and funisitis. This study was conducted to examine the relationship between an elevation in amniotic fluid IL-6 in the midtrimester and preterm delivery at or before 32 weeks of gestation, and the amniotic fluid concentration of IP-10 and preterm delivery after 32 weeks of gestation.

MATERIALS AND METHODS

This cohort study included 847 consecutive women undergoing genetic midtrimester amniocentesis; in 796 cases, amniotic fluid and pregnancy outcome was available for study after exclusion of abnormal karyotype and/or fetal congenital anomalies. Spontaneous preterm delivery was defined as early (≤32 weeks) or late (after 32 completed weeks of pregnancy). The amniotic fluid and maternal blood concentrations of IL-6 and IP-10 were measured by specific immunoassays.

RESULTS

1) The prevalence of preterm delivery was 8.3% (66/796), while those of early and late spontaneous preterm delivery were 1.5% (n=12), and 4.5% (n=36), respectively; 2) patients who had a spontaneous preterm delivery after 32 weeks of gestation had a higher median amniotic fluid IP-10 concentration than those who delivered at term [median 713 pg/mL, inter-quartile range (IQR) 509-1427 pg/mL vs. median 589 pg/mL, IQR 402-953 pg/mL; P=0.006] and an elevation of amniotic fluid IP-10 concentration above 502 pg/mL (derived from an ROC curve) was associated with late spontaneous preterm delivery [odds ratio 3.9 (95% CI 1.6-9.9)]; 3) patients who had a spontaneous preterm delivery ≤32 weeks of gestation had a higher median amniotic fluid IL-6 concentration than those who delivered at term [median 2052 pg/mL, IQR 435-3015 pg/mL vs. median 414 pg/mL, IQR 209-930 pg/mL; P=0.006], and an elevated amniotic fluid IL-6 concentration above 1740 pg/mL (derived from an ROC curve) was associated with early spontaneous preterm delivery [odds ratio 9.5 (95% CI 2.9-31.1)]; 4) subclinical intra-amniotic inflammation, defined as an elevation of IL-6 (≥2.9 ng/mL) or IP-10 (≥2.2 ng/mL) concentration above the 95th percentile of patients who had uncomplicated term delivery (n=652 for IL-6 and n=633 for IP-10), was observed in 6.3% (50/796) and 5.8% (45/770) of cases, respectively. Although each type of inflammation is a risk factor for spontaneous preterm delivery, many patients had a term delivery without complication; 5) the amniotic fluid in the midtrimester did not contain microorganisms detectable with cultivation techniques.

CONCLUSIONS

INTRA-amniotic inflammation is heterogeneous. Some patients have elevated amniotic fluid concentrations of IL-6, and are at risk for spontaneous preterm delivery before 32 weeks of gestation, while others have an elevated IP-10 (a chemotactic T-cell chemokine) and such patients are at risk for spontaneous preterm delivery after 32 weeks of gestation. A fraction of patients have subclinical intra-amniotic inflammation and deliver at term. The clinical significance of this condition remains to be determined.

Elevated levels of a disintegrin and metalloproteinase 8 in gingival crevicular fluid of patients with periodontal diseases

BACKGROUND

A disintegrin and metalloproteinase 8 (ADAM8) is involved in inflammation and is essential for osteoclastogenesis. Elevated ADAM8 levels are detected in human serum and other body fluids in several inflammatory conditions. Therefore, we hypothesized that ADAM8 levels are also raised in gingival crevicular fluid (GCF) of patients with periodontal diseases.

METHODS

Forty-five patients with periodontal diseases (n = 15 for each group: the group of patients with gingivitis, the group with aggressive periodontitis [AgP], and the group with chronic periodontitis [CP]) and 15 volunteers who exhibited healthy gingiva were recruited. Four periodontal parameters, gingival index, plaque index, probing depth, and clinical attachment level, were recorded before GCF collection. The presence of ADAM8 in GCF was shown by immunoblotting using anti-human ADAM8 polyclonal antibody against its prodomain, and the ADAM8 levels were measured by an enzyme-linked immunosorbent assay.

RESULTS

Four immunoreactive bands at 120, 70, 50, and <30 kDa were detected in the groups of patients with periodontitis, whose intensities were stronger than those in the group of patients with gingivitis, consistent with significantly greater ADAM8 levels in both groups of patients, with either CP or AgP, than those in the group of patients with gingivitis and in the group that was healthy (P <0.001). Moreover, the ADAM8 levels correlated significantly with the four periodontal parameters (P <0.001), indicating that ADAM8 levels are positively associated with the degree of periodontal tissue inflammation and destruction.

CONCLUSIONS

The ADAM8 levels are elevated in the GCF of patients with periodontal diseases, including gingivitis, CP, and AgP, in comparison to control participants who are healthy, and they correlate with four clinical parameters that reflect the degree of disease severity.

Immune aspects and myometrial actions of progesterone and CRH in labor

Progesterone and corticotropin-releasing hormone (CRH) have a critical role in pregnancy and labor, as changes related to these hormones are crucial for the transition from myometrial quiescence to contractility. The mechanisms related to their effect differ between humans and other species, thus, despite extensive research, many questions remain to be answered regarding their mediation in human labor. Immune responses to progesterone and CRH are important for labor. Progesterone acts as an immunomodulator which controls many immune actions during pregnancy, and its withdrawal releases the inhibitory action on inflammatory pathways. In humans, a "functional" progesterone withdrawal occurs with onset of labor through changes in progesterone metabolism, progesterone receptors, and other molecules that either facilitate or antagonize progesterone function. Placental CRH acts on the fetal pituitary-adrenal axis to stimulate adrenal production of androgens and cortisol and also acts directly on myometrial cells via its receptors. CRH also affects inflammatory signals and vice versa. Interactions between progesterone and CRH additionally occur during labor. We describe the role of these two hormones in human myometrium and their interactions with the immune system during labor.

Hematologic profile of the fetus with systemic inflammatory response syndrome

OBJECTIVE

The fetal inflammatory response syndrome (FIRS) is associated with impending onset of preterm labor/delivery, microbial invasion of the amniotic cavity and increased perinatal morbidity. FIRS has been defined by an elevated fetal plasma interleukin (IL)-6, a cytokine with potent effects on the differentiation and proliferation of hematopoietic precursors. The objective of this study was to characterize the hematologic profile of fetuses with FIRS.

STUDY DESIGN

Fetal blood sampling was performed in patients with preterm prelabor rupture of membranes and preterm labor with intact membranes (n=152). A fetal plasma IL-6 concentration ≥ 11 pg/mL was used to define FIRS. Hemoglobin concentration, platelet count, total white blood cell (WBC) count, differential count, and nucleated red blood cell (NRBC) count were obtained. Since blood cell count varies with gestational age, the observed values were corrected for fetal age by calculating a ratio between the observed and expected mean value for gestational age.

RESULTS

1) The prevalence of FIRS was 28.9% (44/152); 2) fetuses with FIRS had a higher median corrected WBC and corrected neutrophil count than those without FIRS (WBC: median 1.4, range 0.3-5.6, vs. median 1.1, range 0.4-2.9, P=0.001; neutrophils: median 3.6, range 0.1-57.5, vs. median 1.8, range 0.2-13.9, P<0.001); 3) neutrophilia (defined as a neutrophil count >95th centile of gestational age) was significantly more common in fetuses with FIRS than in those without FIRS (71%, 30/42, vs. 35%, 37/105; P<0.001); 4) more than two-thirds of fetuses with FIRS had neutrophilia, whereas neutropenia was present in only 4.8% (2/42); 5) FIRS was not associated with detectable changes in hemoglobin concentration, platelet, lymphocyte, monocyte, basophil or eosinophil counts; and 6) fetuses with FIRS had a median corrected NRBC count higher than those without FIRS. However, the difference did not reach statistical significance (NRBC median 0.07, range 0-1.3, vs. median 0.04, range 0-2.3, P=0.06).

CONCLUSION

The hematologic profile of the human fetus with FIRS is characterized by significant changes in the total WBC and neutrophil counts. The NRBC count in fetuses with FIRS tends to be higher than fetuses without FIRS.

Novel biomarkers for the prediction of the spontaneous preterm birth phenotype: a systematic review and meta-analysis

BACKGROUND

Being able to predict preterm birth is important, as it may allow a high-risk population to be selected for future interventional studies and help in understanding the pathways that lead to preterm birth.

OBJECTIVE

To investigate the accuracy of novel biomarkers to predict spontaneous preterm birth in women with singleton pregnancies and no symptoms of preterm labour.

SEARCH STRATEGY

Electronic searches in PubMed, Embase, Cinahl, Lilacs, and Medion, references of retrieved articles, and conference proceedings. No language restrictions were applied.

SELECTION CRITERIA

Observational studies that evaluated the accuracy of biomarkers proposed in the last decade to predict spontaneous preterm birth in asymptomatic women. We excluded studies in which biomarkers were evaluated in women with preterm labour.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data on study characteristics, quality, and accuracy. Data were arranged in 2 × 2 contingency tables and synthesised separately for spontaneous preterm birth before 32, 34, and 37 weeks of gestation. We used bivariate meta-analysis to estimate pooled sensitivities and specificities, and calculated likelihood ratios (LRs).

MAIN RESULTS

A total of 72 studies, including 89,786 women and evaluating 30 novel biomarkers, met the inclusion criteria. Only three biomarkers (proteome profile and prolactin in cervicovaginal fluid, and matrix metalloproteinase-8 in amniotic fluid) had positive LRs > 10. However, each of these biomarkers was evaluated in only one small study. Four biomarkers had a moderate predictive accuracy (interleukin-6 and angiogenin, in amniotic fluid; human chorionic gonadotrophin and phosphorylated insulin-like growth factor binding protein-1, in cervicovaginal fluid). The remaining biomarkers had low predictive accuracies.

CONCLUSIONS

None of the biomarkers evaluated in this review meet the criteria to be considered a clinically useful test to predict spontaneous preterm birth. Further large, prospective cohort studies are needed to evaluate promising biomarkers such as a proteome profile in cervicovaginal fluid.

Amniotic fluid urocortin, CRF, oestriol, dehydroepiandrosterone sulfate and cortisol concentrations at mid-trimester: putative relationship with preterm delivery

OBJECTIVE

Stress-related peptide and steroid hormones are involved in the pathogenesis of preterm delivery, even though their clinical usefulness as predictive markers of preterm delivery remains unclear. The present study evaluated whether mid-trimester amniotic fluid concentrations of stress-related peptides, that is corticothophin-releasing factor (CRF) and urocortin (Ucn) and feto-placental steroids (oestriol, DHEA-S and cortisol) correlated with preterm delivery.

STUDY DESIGN

It is a retrospective case-control study. Healthy women (n=130) undergoing amniocentesis at mid-gestation for genetic indications, of whom 15 had a preterm delivery (cases) and 115 delivered at term (controls). CRF, urocortin, cortisol, DHEA-S and oestriol concentrations were measured by specific and sensitive immunoenzymatic assays.

RESULTS

Amniotic fluid urocortin concentrations in the cases (0.50+/-0.07 ng/ml) (M+/-SD) were significantly lower (P<0.0001) than in the control group (0.90+/-0.26 ng/ml), while CRF concentrations did not differ between the cases (1.52+/-0.39 ng/ml) and control group (1.64+/-0.68 ng/ml). Amniotic fluid cortisol (17.71+/-3.72 ng/ml vs. 17.32+/-3.17 ng/ml), DHEA-S (0.16+/-0.06 ng/ml vs. 0.17+/-0.09 ng/ml) and oestriol (4.68+/-1.95 ng/ml vs. 4.79+/-1.84 ng/ml) concentrations were similar in the two groups.

CONCLUSIONS

The low amniotic fluid concentrations of urocortin at mid-trimester may be a signal of predisposition to preterm delivery, while the unchanged CRF and steroid hormones concentrations in women delivering preterm suggest that this mechanisms are not yet activated at mid-trimester.

The role of human beta defensins 2 and 3 in the second trimester amniotic fluid in predicting preterm labor and premature rupture of membranes

AIM

Human beta defensins 2 (HBD2) and 3 (HBD3) are peptides expressed in the amnion and chorion. This is a matched case control study conducted in our Department to determine whether second trimester amniotic fluid HBD2 and HBD3 concentrations measured at the time of genetic amniocentesis could be potential markers of preterm labor prediction.

METHODS

Amniotic fluid HBD2 and HBD3 were determined by an enzyme-linked immunosorbent assay (ELISA) Women with preterm labor were defined as cases (N=41) while for each case a woman matched for age delivering at term served as control (N=41). Subgroup analysis was conducted to examine possible associations of HBD2 and HBD3 in cases of premature rupture of membranes. Nineteen women with preterm labor and premature rupture of membranes were defined as cases while for every case a woman matched for maternal age delivering at term served as control (N1=19). Results were presented as odds ratios (OR) and 95% confidence intervals. Statistical analysis used STATA 8.2 and SPSS 11.5 edition. A P-value of <0.05 was considered statistically significant.

RESULTS

Amniotic fluid concentrations of HBD2 at the time of genetic amniocentesis were positively associated with preterm premature rupture of membranes (P=0.028), but not with preterm labour. No association of HBD3 and preterm birth was documented.

CONCLUSION

Second trimester amniotic fluid HBD2 might be a predictor of premature rupture of membranes.

Developmental immunotoxicology (DIT): windows of vulnerability, immune dysfunction and safety assessment

Developmental immunotoxicity (DIT) is an increasing health concern since DIT outcomes predispose children to those diseases that have been on the rise in recent decades (e.g., childhood asthma, allergic diseases, autoimmune conditions, childhood infections). The enhanced vulnerability of the developing immune system for environmental insult is based on unique immune maturational events that occur during critical windows of vulnerability in early life. The semi-allogeneic pregnancy state, with suppression of graft rejection and associated skewing of the fetal and neonatal immune system, also influences the specific nature of DIT outcomes. In the exposed offspring, targeted immunosuppression can co-exist with an increased risk of allergic and/or autoimmune disease. Because with DIT immune dysfunction rather than profound immunosuppression is the greater concern, testing approaches should emphasize multi-functional assessment. Beyond T-cells, dendritic cells and macrophages are sensitive targets. The last-trimester fetus and the neonate are normally depressed in T(H)1-dependent functions and postnatal acquisition of needed T(H)1 capacity is a major concern with DIT. With this in mind, assessment should include a measure of T(H)1-dependent cell-mediated immunity [cytotoxic T-lymphocyte (CTL) activity or delayed-type hypersensitivity (DTH) response] in conjunction with a multi-isotype T-dependent antibody response (TDAR) and evaluation of innate immunity (e.g., NK activity). Other parameters such as immune histology, immunophenotyping, cytokine responses, and organ weights can be useful when included with immune functional evaluation. A multifunctional DIT protocol using influenza challenge is presented as one example of an approach that permits dysfunction and misregulation to be evaluated.

A role for CXCL13 (BCA-1) in pregnancy and intra-amniotic infection/inflammation

OBJECTIVES

CXCL13 is a potent chemokine, produced by mature and recently recruited macrophages to sites of inflammation, which has antimicrobial and anti-angiogenic properties. The purpose of this study was to: (1) determine whether CXCL13 is present in maternal serum, umbilical cord blood, and amniotic fluid (AF); (2) to determine if AF concentration changes with intra-amniotic infection/inflammation (IAI); and (3) to localize the production of CXCL13 in chorioamniotic membranes and umbilical cord.

STUDY DESIGN

A cross-sectional study on maternal serum was performed including patients in the following groups: (1) non-pregnant women (n = 20), (2) normal pregnant women (n = 49), (3) patients at term not in labor (n = 30), and (4) patients in spontaneous labor at term (n = 29). Umbilical cord blood was collected from term neonates with (n = 30) and without labor (n = 28). Amniotic fluid was obtained from patients in the following groups: (1) midtrimester (n = 65); (2) term not in labor (n = 22); (3) term in labor (n = 47); (4) preterm labor (PTL) with intact membranes leading to term delivery (n = 70); and (5) PTL leading to preterm delivery with IAI (n = 79) and without IAI (n = 60). CXCL13 concentrations were determined by enzyme-linked immunosorbent assay. Chorioamniotic membranes and umbilical cords were examined with immunohistochemistry. Non-parametric statistics were used for analysis.

RESULTS

(1) CXCL13 was present in 100% of serum and cord blood samples, and 99% of AF samples (339/343). (2) Serum CXCL13 concentration was significantly higher in pregnant women when compared to non-pregnant women (median 313.3 pg/mL (interquartile range (IQR) 197.2-646.9) vs. 40.5 pg/mL (IQR 29.5-93.5), respectively; p < 0.001). (3) Serum CXCL13 concentration decreased with advancing gestational age (Spearman's Rho = -0.424; p < 0.001). (4) There were no significant differences in the median serum CXCL13 concentration between women at term with and without labor (371.6 pg/mL (IQR 194.3-614.3) vs. 235.1 pg/mL (IQR 182.8-354.7), respectively; p = 0.6). (5) The concentration of CXCL13 in AF did not change with gestational age (p = 0.1). (6) Patients with PTL and delivery with IAI had a significantly higher median concentration of CXCL13 than those without IAI (median 513.2 pg/mL (IQR 199.7-2505.5) vs. 137.3 pg/mL (IQR 96.7-209.6), respectively; p < 0.001) and those who delivered at term (133.7 pg/mL (IQR 97.8-174.8); p < 0.001). (7) Spontaneous labor did not result in a change in the median AF concentration of CXCL13 (labor: 86.9 pg/mL (IQR 55.6-152.0) vs. no labor: 77.8 pg/mL (IQR 68.0-98.0); p = 0.8). (8) CXCL13 was immunolocalized to macrophages in fetal membranes and umbilical vein.

CONCLUSIONS

(1) We report for the first time the presence of CXCL13 in AF. (2) AF CXCL13 concentrations are dramatically increased in IAI. (3) Unlike other chemokines, AF and serum CXCL13 concentrations did not change with spontaneous parturition.

Inflammatory reaction and implantation: the new entries PTX3 and D6

Successful embryonic implantation implies anchoring the conceptus in the maternal uterine wall, establishing a vascular supply to enable optimal growth and development of the conceptus, and promoting tolerance of fetal alloantigens encoded by paternal genes. To achieve these goals, complex molecular dialogues take place among the maternal endometrium, the conceptus, and the placenta. Several factors are involved in the fetal-maternal interaction, including hormones, growth factors, cytokines, chemokines, adhesion molecules, extracellular matrix components, and matrix-degrading enzymes. This complex cross-talk results in the induction of a local inflammatory response and a state of systemic inflammation, as revealed by leukocytosis, endothelium activation, increased activity of innate immune cells, and increased levels of inflammatory cytokines and chemokines. The enriched cytokine milieu associated to implantation is likely to control trophoblast migration and differentiation, leukocyte influx and activation, complement activation, as well as angiogenic and angiostatic processes in the implantation site. Finally, these mediators play a key role in tuning the immune responses to protect the fetus from infections as well as from maternal rejection. Here, the role of pro-inflammatory networks activated in implantation will be discussed. In particular, emphasis will be put on two new players involved in regulating inflammation at the maternal-fetal interface: the long pentraxin PTX3 and the decoy receptor for inflammatory chemokines D6.

Chemokine decoy receptors: new players in reproductive immunology

Chemokines are multifunctional molecules with roles in leukocyte trafficking and developmental processes. Both fetal and maternal components of the placenta produce chemokines, which control leukocyte trafficking observed in the placenta. Thus, chemokines play roles in the balance between protection of the developing embryo/fetus and tolerance of its hemiallogeneic tissues. Recently, a group of chemokine receptors, which include D6, DARC, and CCX-CKR, have been described as "silent" receptors by virtue of their inability to activate signal transduction events leading to cell chemoattraction. Here we review in vitro and in vivo evidence indicating that chemokine "silent" receptors regulate innate and adaptive immunity behaving as decoy receptors that support internalization and degradation of chemotactic factors, and discuss available information on their potential role in reproductive immunology.