Elevated interleukin-8 in cervical mucus as an indicator for treatment to prevent premature birth and preterm, pre-labor rupture of membranes: a prospective study

Management of a pregnant woman with a large cervical polyp and moderate genital bleeding in the first trimester

Polypectomy during pregnancy is known to be a risk for spontaneous late miscarriage or preterm delivery. We managed a pregnant woman in her 30s with a large cervical polyp without polypectomy, and we administered probiotics including Clostridium butyricum and 17-alpha-hydroxyprogesterone caproate. As a result, she delivered a healthy baby at 38 weeks.

Pathological roles of antimicrobial peptides and pro-inflammatory factors secreted from the cervical epithelium in Gardnerella vaginalis-abundant vaginal flora in pregnancy

Bacterial vaginosis due to Gardnerella vaginalis (GV) is one of the main causes of preterm birth. Antimicrobial function of the cervical glands prevents ascending pathogen infection. This study investigated the effect of GV on the cervical gland cells. We examined the correlation between GV and neutrophil elastase in the cervical mucous obtained from pregnant women's clinical samples. Culture supernatants (sup) of GV and Lactobacillus crispatus (LC) were added to human immortalized cervical gland cells (EndoCx). Quantitative reverse transcription PCR (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA) were used to examine the effects on the production of antimicrobial peptides (AMPs), secretory leukocyte peptidase inhibitor (SLPI), and Elafin. mRNA microarray analysis revealed the expression profile of GV-exposed EndoCx. Moreover, the antimicrobial activity of Elafin against LC and GV was investigated. In the clinical samples, neutrophil elastase was increased in the GV-positive cervical mucous. In an in vitro assay, RT-qPCR and ELISA showed that GV-sup enhanced the secretion of Elafin, but not SLPI, from EndoCx, whereas LC-sup did not. mRNA microarray assay and ELISA results demonstrated that GV-sup enhanced the proinflammatory pathway and interleukin (IL)- 8 secretion from EndoCx as well as cell adhesion and tight junction pathways. Moreover, GV-sup directly enhanced Elafin and IL-8 secretion from the cervical gland cells. In the GV-abundant vaginal flora, IL-8 level increased the neutrophil elastase activity and Elafin inhibited the elastase activity to protect from tissue damage and infection. Thus, the balance of IL-8-induced neutrophil and Elafin-induced antiprotease activities may be crucial in preterm labor.

Surgical management of endocervical and decidual polyps during pregnancy: systematic review and meta-analysis

PURPOSE

To evaluate the impact of endocervical and decidual polypectomy on obstetrical outcomes of pregnant women.

METHODS

MEDLINE, Scopus, ClinicalTrials.gov, Scielo, EMBASE, Cochrane Library at the CENTRAL Register of Controlled Trials, and LILACS were searched from inception to April 2021. No language or geographical restrictions were applied. Inclusion criteria regarded observational studies concerning pregnant women with a cervical lesion who underwent cervical polypectomy. Co-primary outcomes were incidence of late pregnancy loss and preterm birth in women with endocervical or decidual polypectomy as well as polypectomy versus expectant management. Random effect meta-analyses to calculate risk ratio (RR) with 95% confidence interval (CI) were performed. Quality assessment of included papers was performed using Newcastle-Ottawa Scale criteria.

RESULTS

Three studies, with data provided for 3097 women, were included in quantitative analysis, with comparisons between endocervical and decidual polyps extracted from two studies and 156 patients. After a first trimester endocervical or decidual polypectomy, no significant differences were found for late pregnancy losses (RR 0.29 [95% CI 0.05, 1.80], I² = 11%). Risk for preterm birth was significantly higher for decidual polyps' removal (RR 6.13 [95% CI 2.57, 14.59], I² = 0%). One paper compared cervical polypectomy vs expectant management, with increased incidence of late pregnancy loss (4/142 vs 5/2799; p < 0.001) and preterm birth (19/142 vs 115/2799; p < 0.001) in women subjected to polypectomy.

CONCLUSIONS

Evidence regarding the removal of cervical polyps in pregnancy is extremely limited. However, the removal of either decidual or endocervical polyps seems associated with increased risk of pregnancy loss and preterm birth, with increased preterm birth risk following endocervical rather than decidual polypectomy.

Fusobacterium nucleatum and its associated systemic diseases: epidemiologic studies and possible mechanisms

Background

Fusobacterium nucleatum (F. nucleatum) is an anaerobic oral commensal and the major coaggregation bridge organism linking early and late colonisers. In recent years, a large number of studies suggest that F. nucleatum is closely related to the development of various systemic diseases, such as cardiovascular diseases, adverse pregnancy outcomes, inflammatory bowel diseases, cancer, Alzheimer's disease, respiratory infection, rheumatoid arthritis, etc.

Objective

To review the effect of F. nucleatum on systemic diseases and its possible pathogenesis and to open new avenues for prevention and treatment of F. nucleatum-associated systemic diseases.

Design

The research included every article published up to July 2022 featuring the keywords 'Systemic diseases' OR 'Atherosclerotic cardiovascular diseases' OR 'Atherosclerosis' OR 'Adverse pregnancy outcomes' OR 'Inflammatory bowel disease' OR 'Ulcerative colitis' OR 'Crohn’s disease' OR 'Cancers' OR 'Oral squamous cell carcinomas' OR 'Gastrointestinal cancers' OR 'Colorectal cancer' OR 'Breast cancer' OR 'Genitourinary cancers' OR 'Alzheimer’s disease ' OR 'Rheumatoid arthritis' OR 'Respiratory diseases' AND 'Fusobacterium nucleatum' OR 'Periodontal pathogen' OR 'Oral microbiota' OR 'Porphyromonas gingivalis' and was conducted in the major medical databases.

Results

F. nucleatum can induce immune response and inflammation in the body through direct or indirect pathways, and thus affect the occurrence and development of systemic diseases. Only by continuing to investigate the pathogenic lifestyles of F. nucleatum will we discover the divergent pathways that may be leveraged for diagnostic, preventive and therapeutic purposes.

Antibody microarray analysis of the amniotic fluid proteome for predicting the outcome of rescue cerclage in patients with cervical insufficiency

Little is known about the biomarkers that can identify patient candidates suitable for rescue cerclage procedure. The purpose of the study was to identify novel biomarkers in amniotic fluid (AF) that can predict the outcome of rescue cerclage in patients with cervical insufficiency by using an antibody microarray. This case–control study was conducted using AF samples collected from singleton pregnant women who underwent rescue cerclage following a diagnosis of cervical insufficiency (19–25 weeks). Patients were divided into case (n=20) and control (n=20) groups based on the occurrence of spontaneous preterm delivery (SPTD) at <34 weeks of gestation after cerclage placement. The AF proteomes were analyzed using an antibody microarray for biomarker discovery work. Ten candidate biomarkers of interest were validated by enzyme-linked immunosorbent assay (ELISA). Thirty-one molecules studied showed significant intergroup differences (≥two-fold change in signal intensity). Validation by ELISA confirmed significantly higher levels of a proliferation-inducing ligand (APRIL), S100 calcium-binding protein A8/A9 complex (S100 A8/A9), tissue inhibitors of metalloproteinase-1 (TIMP-1), macrophage inflammatory protein-1α (MIP-1α), and interleukin-8 (IL-8) in women who had SPTD at <34 weeks. Of these, AF S100 A8/A9 and TIMP-1 levels were independent of other potentially confounding factors (e.g., cervical dilatation). S100 A8/A9 had the highest area under the curve (AUC) at 0.857. Using protein–antibody microarray technology, we identified differentially expressed proteins (DEPs) and several novel biomarkers (APRIL, IL-8, MIP-1α, S100 A8/A9, and TIMP-1) in AF from women who had SPTB at <34 weeks after cerclage for cervical insufficiency. These data can provide an insight into the molecular mechanisms underlying SPTD after rescue cerclage in patients with cervical insufficiency.

Receptor-interacting protein kinase 2 contributes to host innate immune responses against Fusobacterium nucleatum in macrophages and decidual stromal cells

PROBLEM

Chorioamnionitis is caused by a bacterial infection that ascends from the vagina and can cause adverse pregnancy outcomes (APOs). Fusobacterium nucleatum (F. nucleatum) is a periodontal pathogen associated with the occurrence of APOs. In this study, we evaluated whether receptor-interacting protein kinase 2 (Ripk2), an adaptor protein of the cytosolic receptors nucleotide-binding oligomerization domain (NOD)1 and NOD2, in macrophages and human decidual stromal cells (hDSCs) contributes to immune responses against F. nucleatum.

METHOD OF STUDY

Bone marrow-derived macrophages (BMDMs) isolated from wild-type (WT) and Ripk2-deficient mice and hDSCs were cultured with F. nucleatum (MOI 1, 10, 100). BMDMs and hDSCs were assessed using enzyme-linked immunosorbent assay, Western blot analysis, real-time PCR, and nitrite assay.

RESULTS

Fusobacterium nucleatum-induced production of IL-6, but not of TNF-α and IL-10, was lower in Ripk2-deficient BMDMs than in WT cells. Western blotting revealed a decrease in F. nucleatum-induced p65 phosphorylation in Ripk2-deficient macrophages, whereas mitogen-activated protein kinases activation was comparable between WT and Ripk2-deficient cells. The production of nitric oxide (NO) in response to F. nucleatum and the gene and protein expression of inducible NO synthase was impaired in Ripk2-deficient BMDMs. In hDSCs, F. nucleatum upregulated the gene and protein expression of NOD1, NOD2, and Ripk2 in a time-dependent manner. F. nucleatum also increased the production of IL-6, CXCL8, and CCL2, whereas this production was decreased by the Ripk2 inhibitors SB203580 and PP2.

CONCLUSIONS

In conclusion, Ripk2 signaling appears to contribute to the F. nucleatum-induced immune response and can be a preventive and therapeutic target against APOs.

Abnormal uterine inflammation in obstetric syndromes: molecular insights into the role of chemokine decoy receptor D6 and inflammasome NLRP3

The adaptation of the uterine environment into a favorable immunological and inflammatory milieu is a physiological process needed in normal pregnancy. A uterine hyperinflammatory state, whether idiopathic or secondary to hormonal or organic uterine disorders (polycystic ovary syndromes, endometriosis/adenomyosis and fibroids), negatively influences the interactions between decidua and trophoblast, early in gestation, and between chorion and decidua later in pregnancy. Abnormal activation of uterine inflammatory pathways not only contributes to the pathogenesis of the obstetric syndromes, i.e. recurrent pregnancy loss (RPL), pre-term delivery (PTD) and pre-eclampsia (PE), but also to correlates with severity. In this review, we summarize recent advances in the knowledge of uterine molecular mechanisms of inflammatory modulation in normal pregnancy and obstetric syndromes (RPL, PTD and PE). In particular, we focus on two regulators of uterine/placental inflammation: the NLRP3 inflammasome and the chemokines decoy receptor D6. We performed comprehensive review of the literature in PubMed and Google Scholar databases from 1994 to 2018. The available evidence suggests that: (i) the expression of inflammasome NLRP3 is increased in the endometrium of women with unexplained RPL, in the chorioamniotic membranes of women with PTL and in the placenta of women with PE; (ii) there is a role for abnormal expression and function of D6 decoy receptor at the feto-maternal interface in cases of RPL and PTD and (iii) the function of placental D6 decoy receptor is impaired in PE. A wider comprehension of the inflammatory molecular mechanisms involved in the pathogenesis of the obstetric syndromes might lead to the identification of new potential therapeutic targets.

Role of maternal interleukin-8 (IL-8) in normal-term birth in the human

Cytokines are the main factors involved in the normal functions of the placenta and delivery process. The aim of this project was to compare serum levels of interleukin-8 (IL-8), IL-6, tumour necrosis factor α (TNF-α) and transforming growth factor β (TGF-β) in term and prolonged-pregnancy mothers and their neonates. This study was performed on 240 participants including 60 term and prolonged-pregnancy neonates and their corresponding mothers. Serum levels of IL-8, IL-6, TNF-α and TGF-β were evaluated by the enzyme-linked immunosorbent assay technique. The results revealed that IL-8 serum levels were significantly lower in the prolonged-pregnancy mothers and their neonates when compared with term mothers and their neonates. Data analysis also revealed a negative correlation between TGF-β and age of prolonged-pregnancy mothers. A poor positive correlation between IL-6 and head circumference of term neonates was also observed. IL-8 may play crucial roles in the process of on-time delivery and age may significantly affect TGF-β production in prolonged-pregnancy mothers. Pro-inflammatory cytokines, such as IL-6, can also be considered as main factors involved in fetal growth.

Does tumour necrosis factor alpha-induced cyclooxygenase-2 expression lead to spontaneous abortion in Chlamydia trachomatis-infected women

Cytokines might be involved in spontaneous abortion by triggering inflammatory mediators (Cyclooxygenases (Cox)) leading to spontaneous abortion in Chlamydia trachomatis (Ct)-infected women. Study aimed to quantitate the expression of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-8) and Cox-2 in endometrial curettage tissue (ECT) of Spontaneous Aborters (SA). SA (n = 135) and 120 age-matched controls were enrolled from SJH, New Delhi, India. PCR was performed for detection of Ct MOMP gene (537 bp) in ECT. mRNA expression of pro-inflammatory cytokines and Cox-2 was assessed by real-time qPCR. Data was statistically evaluated. 14.8% SA were diagnosed as Ct-positive. Elevated expression of TNF-α, IFN-γ, IL-8 and Cox-2 was observed in Ct-infected SA. Ct-positive recurrent aborters showed significantly higher cytokine expression. Significant positive correlation was found between expression of Cox-2 and TNF-α in infected SA. Data suggested an increased expression of Th-1 cytokines, particularly TNF-α that induced Cox-2 expression in ECT, leading to spontaneous abortion in Ct-infected pregnant women.

Risk factors for spontaneous miscarriage above 12 weeks or premature delivery in patients undergoing cervical polypectomy during pregnancy

Background

It currently remains unknown whether the resection of cervical polyps during pregnancy leads to miscarriage and/or preterm birth. This study evaluated the risk of spontaneous PTB below 34 or 37 weeks and miscarriage above 12 weeks in patients undergoing cervical polypectomy during pregnancy.

Methods

This was a retrospective monocentric cohort study of patients undergoing cervical polypectomy for clinical indication. Seventy-three pregnant women who underwent polypectomy were selected, and risk factors associated with miscarriage above 12 weeks or premature delivery below 34 or 37 weeks were investigated. A multivariable regression looking for predictors of spontaneous miscarriage > 12 weeks and PTB < 34 or 37 weeks were performed.

Results

Sixteen patients (21.9%, 16/73) had spontaneous delivery at < 34 weeks or miscarriage above 12 weeks. A univariate analysis showed that bleeding before polypectomy [odds ratio (OR) 7.7, 95% confidence interval (CI) 1.6–37.3, p = 0.004], polyp width ≥ 12 mm (OR 4.0, 95% CI 1.2–13.1, p = 0.005), the proportion of decidual polyps (OR 8.1, 95% CI 1.00–65.9, p = 0.024), and polypectomy at ≤10 weeks (OR 5.2, 95% CI 1.3–20.3, p = 0.01) were significantly higher in delivery at < 34 weeks than at ≥34 weeks. A logistic regression analysis identified polyp width ≥ 12 mm (OR 11.8, 95% CI 2.8–77.5, p = 0.001), genital bleeding before polypectomy (OR 6.5, 95% CI 1.2–55.7, p = 0.025), and polypectomy at ≤10 weeks (OR 5.9, 95% CI 1.2–45.0, p = 0.028) as independent risk factors for predicting delivery at < 34 weeks. Polyp width ≥ 12 mm and bleeding before polypectomy are risk factors for PTB < 37 wks.

Conclusions

Our cohort of patients undergoing polypectomy in pregnancy have high risks of miscarriage or spontaneous premature delivery. It is unclear whether these risks are given by the underlying disease, by surgical treatment or both. This study establishes clinically relevant predictors of PTB are polyp size> 12 mm, bleeding and first trimester polypectomy. PTB risks should be exposed to patients and extensively discussed with balancing against the benefits of intervention in pregnancy.

17OHP-C in patients with spontaneous preterm labor and intact membranes: is there an effect according to the presence of intra-amniotic inflammation?

PROBLEM

It is not known whether 17-alpha-hydroxyprogesterone caproate (17OHP-C) is effective for preventing preterm delivery with an episode of preterm labor (PTL) with or without intra-amniotic inflammation/infection.

METHODS OF STUDY

This was a retrospective cohort study. One hundred and seven PTL patients were selected and divided into a 17OHP-C group (use of 17OHP-C: n = 53) and a no-treatment group (no use of 17OHP-C: n = 54). Moreover, the patients were divided into three subgroups (subgroup A: without intra-amniotic inflammation, B: with mild intra-amniotic inflammation, and C: with severe intra-amniotic inflammation) according to their level of amniotic interleukin (IL)-8, and perinatal prognosis was analyzed.

RESULTS

Interval from admission to delivery (days) in the 17OHP-C group (76 [13-126], n = 34) was significantly longer than that in the no-treatment group (50 [8-104], n = 33; P = .012) in subgroup B. In cases without intra-amniotic microbes in subgroup B, a significant prolongation of gestational days was associated with the 17OHP-C group (79 [13-126], n = 25) compared with the no-treatment group (50 [8-104], n = 29; P = .029). However, there were no significant differences in subgroups A or C.

CONCLUSION

17OHP-C could prolong gestational period in limited PTL cases with sterile mild intra-amniotic inflammation.

Non-invasive prediction of preterm birth in women with cervical insufficiency or an asymptomatic short cervix (≤25 mm) by measurement of biomarkers in the cervicovaginal fluid

OBJECTIVE

To determine whether various proteins in the cervicovaginal fluid (CVF) known to be involved in immune regulation, alone or in combination with clinical risk factors, can predict spontaneous preterm delivery (SPTD) in women with cervical insufficiency or a short cervix (≤25 mm).

METHODS

This retrospective cohort study included 62 asymptomatic women with cervical insufficiency (n = 27) or an asymptomatic short cervix (n = 35) at 18-27 weeks. CVF swab samples were taken for assays of vitamin D binding protein (VDBP), interleukin (IL)-8, matrix metalloproteinases (MMP)-9, tissue inhibitor of metalloproteinases (TIMP)-1, and Dickkopf-related protein 3 (DKK3) before cervical examination, and maternal blood was collected for the determination of the C-reactive protein (CRP) level. The primary outcome measurement was SPTD at <32 weeks of gestation. Logistic regression analysis and receiver operating characteristic curves were used for the statistical analyses.

RESULTS

The rate of SPTD at <32 weeks was 40.3% (25/62). The CVF levels of VDBP, TIMP-1, and DKK3, but not IL-8 and MMP-9, were significantly higher in the women who had SPTD at <32 weeks than in those who did not deliver spontaneously at <32 weeks. The women who had SPTD at <32 weeks had a significantly more advanced cervical dilatation at presentation and a higher level of serum CRP. Using the stepwise regression analysis, a prediction model was developed by combining various proteins in the CVF and clinical factors, resulting in the inclusion of cervical dilatation, CVF VDBP, and use of corticosteroids (area under curve, 0.909).

CONCLUSIONS

In women with cervical insufficiency or a short cervix, VDBP, TIMP-1, and DKK3 in the CVF may be useful as non-invasive predictors of SPTD at <32 weeks. A combination of these markers and clinical factors appears to improve the predictability of SPTD compared with the markers alone.

Predictive value of vaginal IL-6 and TNFα bedside tests repeated until delivery for the prediction of maternal-fetal infection in cases of premature rupture of membranes

OBJECTIVE

Examine the predictive value for maternal-fetal infection of routine bedside tests detecting the proinflammatory cytokines, TNFα and IL-6, in the vaginal secretions of women with premature rupture of the membranes (PROM).

STUDY DESIGN

This prospective two-center cohort study included all women hospitalized for PROM over a 2-year period. A bedside test assessed IL-6 and TNFα in vaginal secretions. Both centers routinely tested CRP and leukocytes, assaying both in maternal serum, and analyzed vaginal bacterial flora; all samples were repeated twice weekly until delivery.

RESULTS

The study included 689 women. In cases of preterm PROM (PPROM) before 37 weeks (n=184), a vaginal sample positive for one or more bacteria was the only marker associated with early neonatal infection (OR 5.6, 95%CI; 2.0-15.7). Its sensitivity was 82% (95%CI; 62-94) and its specificity 56% (95%CI; 47-65). All positive markers of infection were associated with the occurrence of chorioamnionitis. In cases of PROM from 37 weeks onward (n=505), only CRP >5mg/dL was associated with early neonatal infection (OR=8.3, 95%CI; 1.1-65.4) or clinical chorioamnionitis (OR=6.8, 95%CI; 1.5-30.0). The sensitivity of CRP >5mg/dL was 91% (95%CI; 59-100) and its specificity 45% (95%CI; 40-51) for predicting early neonatal infection, and 89% (95%CI; 65-99) and 46% (95%CI; 41-51), respectively, for predicting clinical chorioamnionitis.

CONCLUSION

The association of vaginal cytokines with maternal-fetal infection is weak and thus prevents their use as a good predictor of maternal-fetal infection. CRP and vaginal samples may be useful for identifying a group of women at low risk of infection.

Predicting outcomes of emergency cerclage in women with cervical insufficiency using inflammatory markers in maternal blood and amniotic fluid

OBJECTIVE

To identify inflammatory markers in maternal blood and amniotic fluid that can predict outcomes of emergency cerclage in women with cervical insufficiency.

METHODS

This retrospective cohort study included patients at 18-24 weeks of pregnancy who underwent amniocentesis before receiving emergency cerclage for cervical insufficiency between August 2004 and August 2013 at a university teaching hospital in South Korea. Total and differential white blood cell counts were measured during amniocentesis. Amniotic fluid was cultured and analyzed for the presence of interleukin (IL)-6 and IL-8. The primary outcome measure was spontaneous preterm delivery (SPTD) at less than 32weeks of pregnancy following cerclage placement.

RESULTS

Of 37 patients, 18 (49%) experienced SPTD at less than 32weeks of pregnancy. These patients were found to have significantly more advanced cervical dilatation at presentation, as well as higher mean neutrophil-lymphocyte ratios (NLRs) and higher IL-6 and IL-8 levels in amniotic fluid in comparison with those who did not experience SPTD at less than 32weeks of pregnancy. In a multivariable analysis, a high NLR and high amniotic fluid IL-8 levels showed a significant correlation with the occurrence of SPTD at less than 32weeks of pregnancy (P=0.032).

CONCLUSION

Pre-operative NLR and amniotic fluid IL-8 levels may be important markers for predicting emergency cerclage outcomes in women with cervical insufficiency.

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.

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.

Short and inflamed cervix predicts spontaneous preterm birth (COLIBRI study)

OBJECTIVE

To develop a new strategy of predicting spontaneous preterm birth (sPTB) by combination of transvaginal ultrasound (TVUS) assessment and inflammatory proteins detection in vaginal secretions.

METHODS

Prospective study of 87 women referred for cervical length assessment with a standardized TVUS combined to vaginal secretions sampling. Samples were analyzed for presence of 10 cytokines. Main outcome was sPTB (<37 weeks of gestation). Associations were assessed with the chi-square, Fisher's exact test (p < 0.05) and Wald's logistic regression.

RESULTS

sPTB occurred in 25.3% of women at a median gestational age of 35.6 weeks of gestation. Short cervix (<25 mm) (n = 24) was associated with sPTB (p < 0.01) as interleukine (IL)-1β, IL-8 and IL-10 in vaginal secretions (p < 0.05). In multivariate analysis, short cervix and IL-8 in vaginal secretions were independently associated with sPTB (OR 3.58 (95%CI 1.02; 12.61) and 14.55 (95%CI 1.64; 128.83), respectively) as their combination (OR 4.33 (95%CI 1.25; 14.95)). By categorizing cervical length by presence of IL-8, sPTB occurred in 55.6% of women with a short inflamed cervix.

CONCLUSION

COLIBRI study used a novel, single-step method of vaginal secretions sampling during TVUS and demonstrated that combination of short cervix and IL-8 in vaginal secretions is a promising sPTB predictive test.

Rapid evaluation of the absence of inflammation after rupture of membranes

OBJECTIVES

The aim of this study was to validate the results of an immunochromatographic bedside test to detect IL6 and IL8 in vaginal secretions after rupture of membranes (ROM) with results obtained by ELISA tests.

METHODS

A prospective cohort of 60 women with ROM or preterm ROM (PROM) was recruited. An immunochromatographic bedside test was performed with vaginal secretions samplings at admission, every 48 hrs until labor and during labor. Remaining samples were frozen for ELISA analysis. The results of bedside tests were compared to those from ELISA analysis for 114 samples.

RESULTS

With all samples combined, the positive predictive values were 50% for IL6 and 86.8% for IL8 and the negative predictive values were 97.4% for IL6 and 53.3% for IL8. Kappa coefficients were 0.54 for IL6 and 0.41 for IL8.

CONCLUSION

Our findings show that a bedside test can detect the absence of IL6 in vaginal secretions. This result suggests that bedside test could be used for expectant management after premature PROM to inform the attending physician of the absence of inflammation in vaginal secretions.

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.

Use of cervicovaginal fluid for the identification of biomarkers for pathologies of the female genital tract

Cervicovaginal fluid has an important function in the homeostasis and immunity of the lower female genital tract. Analysis of the cervicovaginal fluid proteome may therefore yield important information about the pathogenesis of numerous gynecological pathologies. Additionally, cervicovaginal fluid has great potential as a source of biomarkers for these conditions.

This review provides a detailed discussion about the human cervicovaginal proteome and the proteomics studies performed to characterize this biological fluid. Furthermore, infection-correlated pathological conditions of the female genital tract are discussed for which cervicovaginal fluid has been used in order to identify potential biomarkers. Recent years, numerous studies have analyzed cervicovaginal fluid samples utilizing antibody-based technologies, such as ELISA or Western blotting, to identify biomarkers for preterm birth, premature preterm rupture of membranes, bacterial vaginosis and cervical cancer. The present article will discuss the importance of proteomic technologies as alternative techniques to gain additional meaningful information about these conditions. In addition, the review focuses on recent proteomic studies on cervicovaginal fluid samples for the identification of potential biomarkers. We conclude that the use of proteomic technology for analysis of human cervicovaginal fluid samples is promising and may lead to the discovery of new biomarkers which can improve disease prevention and therapy development.

Management strategies for the prevention of preterm birth: Part II - Update on cervical cerclage

PURPOSE OF REVIEW

Cerclage was devised more than 50 years ago based on the hypothesis that for some women, weakness or malfunction of the cervix has a causative role in the pathway to preterm birth (PTB). There have been many theories around the concept of cervical insufficiency but not much in the way of convincing evidence. The purpose of this review was to follow the recent developments in risk identification and prognostication of PTB in connection with appropriately targeted prophylactic interventions.

RECENT FINDINGS

Sonographic cervical length measurement has emerged as an effective prognosticator for PTB in all populations studied so far, independently of obstetric history, consequently deriving a wider applicability than other predictors of PTB. However, the mechanisms leading to cervical shortening are poorly understood, and it cannot be assumed that all cases with a short cervix would benefit from cerclage. Specific conditions may actually reduce the efficacy and advisability of cerclage. For this reason, attempts have been made recently to further characterize the short cervix, leading to the conclusion that only women with a short cervix in the absence of infection/inflammation may be candidates for cerclage. Furthermore, two recent randomized trials of cerclage in women with short cervix on a second trimester ultrasound suggested a benefit with cerclage in PTB rate reduction only in those cases with a cervical length of less than 15 mm.

SUMMARY

The existent literature has treated PTB prevention focusing exclusively on either progesterone use or cerclage, leaving the practitioners without any guidance on when to proceed with medical or surgical prophylaxis. Understanding that high-risk populations are not homogeneous and no single-approach modality is likely to be generally applicable, we have combined the available evidence on both progesterone and cerclage to provide guidance on how to identify subgroups of women at significantly increased risk for PTB and how to preferentially consider progesterone versus cerclage.

Possible association between screening BV at the prenatal visit and reduced cervical cerclage: multi-center questionnaire in Hokkaido, Japan

AIMS

To study the screening frequency for cervical cancer, Chlamydia trachomatis (CT) infection, and bacterial vaginosis (BV) among pregnant women, and to study the association between administration of these three screening tests and performance of cervical cerclage (CC) in Hokkaido during 2004.

METHODS

Questionnaires were mailed to 70 clinics providing prenatal care only and to 113 hospitals providing prenatal care and performing deliveries. Responses were obtained anonymously.

RESULTS

A total of 6744 pregnant women received prenatal care at the 36 responding clinics and 24 050 deliveries were performed at the 56 hospitals. The percentage of clinics that screened all pregnant women for cervical cancer, CT infection or BV was 66.7%, 69.4% and 33.3%, respectively, and the corresponding percentages among the hospitals were 87.5%, 87.5% and 57.1%, respectively. Pregnant women found to have CT infection or BV, were all treated. Screening for cervical cancer or CT infection was not associated with the frequency of CC. On the other hand, screening for BV was significantly associated with the frequency of CC (P = 0.0006). The frequency of emergency CC was 0.8% among women who received prenatal care at hospitals that did not perform BV screening, while it was only 0.2 or 0.3% among women who received prenatal care at hospitals that performed BV screening on all pregnant women or on those women who were suspected of having BV, respectively.

CONCLUSION

Our results suggest that the frequency of emergency CC may be reduced in women who receive BV screening and subsequent treatment of positive cases during pregnancy.

Cervical fluid cytokines in pregnant women: Relation to vaginal wet mount findings and polymorphonuclear leukocyte counts

OBJECTIVE

The purpose of the study was to measure and compare concentrations of IFN-gamma, IL-8, IL-10 and IL-12 in cervical fluids of pregnant women with normal and pathologic microscopic findings of vaginal wet mount.

STUDY DESIGN

Vaginal samples were obtained from 100 pregnant women (22-32 weeks of gestation) without signs and symptoms of preterm labour (PTL), selected on the basis of the microscopic examination of vaginal wet mounts. Cytokine (IFN-gamma, IL-8, IL-10 and IL-12) concentrations were measured in cervical fluids by an enzyme-linked immunosorbent assay.

RESULTS

The cytokines were found in cervical fluids of the majority of pregnant women, with IFN-gamma and IL-8 detected in all samples. Concentrations of IL-8 were significantly higher in pregnant women with pathologic findings on vaginal wet mount, including elevated polymorphonuclear (PMN) cell counts.

CONCLUSION

A significant correlation between microscopic findings and cervical fluid IL-8 concentrations may make vaginal wet mount microscopy a useful tool for identification of patients with cervicovaginal inflammation, which is considered a risk factor for spontaneous preterm delivery.

Uterine Cervical Inflammatory Cytokines, Interleukin-6 and -8, as Predictors of Miscarriage in Recurrent Cases

PROBLEM

Inflammatory changes frequently occur in cases of second trimester miscarriage or pre-term delivery, but little attention has been paid to this association with recurrent miscarriage. As interleukin-6 and interleukin-8 are inflammatory cytokines reported to be associated with bacterial vaginosis, intrauterine infections, and pre-term delivery, we here investigated whether they might have predictive value for spontaneous abortion in recurrent cases.

METHOD OF STUDY

Cervical mucus and sera were collected at 4-5 weeks' gestation from a total of 59 patients with a history of two or more unexplained consecutive first trimester miscarriages, and examined by enzyme-linked immunosorbent assay. Patients then were followed up without medication and their pregnancy outcomes were compared with the test results.

RESULTS

Of a total of 59 patients, 13 (22%) miscarried subsequently. Both IL-6 and IL-8 in cervical mucus were significantly higher in patients who miscarried subsequently than in those who had a live birth. In addition, there was no correlation between cervical mucus and serum concentrations of IL-6 and IL-8 take at the same time, and there was no relation with serum IL-6 and IL-8 levels between the two groups.

CONCLUSION

Cervical IL-6 and IL-8 might have predictive value for cases of recurrent miscarriage.

Myeloid-related protein-8/14 is associated with proinflammatory cytokines in cervical mucus

Myeloid-related protein-8 (MRP-8), MRP-14, and MRP-8/14 are found in a variety of inflammatory conditions and are involved in the host defense system. The objective of this study was to determine the concentrations of MRP-8, MRP-14, and MRP-8/14 in human cervical mucus and the associations between MRP-8/14 and proinflammatory cytokines. Samples of cervical mucus were obtained using a syringe from sexually active women (n=97) during the preovulatory phase. Samples from seven women were obtained using a swab placed in the cervical canal during the proliferative, preovulatory, and luteal phases. Concentrations of MRP-8, MRP-14, MRP-8/14, IL-1alpha, IL-6, IL-8, and granulocyte elastase were measured using an ELISA. The mean levels of MRP-8, MRP-14, and MRP-8/14 in cervical mucus were 1.87, 0.46, and 23.90microg/ml, respectively. The concentration of MRP-8/14 showed positive correlations with concentrations of IL-1alpha (p<0.0001), IL-8 (p<0.0001), and granulocyte elastase (p<0.0001). However, there were no significant differences in MRP-8/14 levels in the cervical mucus of each patient during the menstrual cycle. MRP-8/14 was mainly detected in human cervical mucus and showed a positive correlation with proinflammatory cytokines. The MRP-8/14 level in cervical mucus may be useful as a marker of inflammation of the uterine cervix.

The role of cervical cerclage in obstetric practice: can the patient who could benefit from this procedure be identified?

This editorial critically examines the definition of "cervical insufficiency." The definition, the clinical ascertainment, efforts to develop an objective method of diagnosis, as well as the nature of cervical disease leading to spontaneous mid-trimester spontaneous abortion and preterm delivery are reviewed. The value and limitations of cervical sonography as a risk assessment tool for spontaneous preterm delivery are appraised. The main focus is on the role of cervical cerclage to prevent an adverse pregnancy outcome. The value of assessing the presence or absence of endocervical inflammation in the outcome of cerclage placement is discussed.

Evaluation of effectiveness of prophylactic cerclage of a short cervix according to interleukin-8 in cervical mucus

OBJECTIVE

This study was undertaken to compare rates of preterm delivery according to cervical mucus interleukin-8 (IL-8) among women who underwent cerclage because of a short cervix.

STUDY DESIGN

This retrospective study included 16,508 patients whose cervical length and cervical mucus IL-8 concentrations were measured between 20 and 24 weeks. A short cervix was defined by a length of 25 mm or less, whereas IL-8 concentrations exceeding 360 ng/mL were considered high. Whether to perform cerclage was decided by clinicians without consideration of IL-8 concentrations.

RESULTS

Among all subjects, a significantly smaller percentage of subjects avoided delivery before 37 weeks when cervical mucus IL-8 was elevated (P = .0302) or the cervix was short (P < .0001). Among patients with a short cervix, preterm delivery was more likely when cervical mucus IL-8 was elevated. Overall, risk of preterm delivery in patients with a short cervix did not differ between those undergoing and not undergoing cerclage. However, among patients with a short cervix, those with normal IL-8 concentrations in cervical mucus were less likely to have preterm delivery if they underwent cerclage (before 37 weeks, 33% vs 54.5%, P = .01; before 34 weeks, 4% vs 13.6%, P = .03). In contrast, when cervical mucus IL-8 was high, delivery before 37 weeks was more likely with than without cerclage (78% vs 54.1%, P = .03).

CONCLUSION

With normal cervical mucus IL-8, cerclage treatment for cervical shortening may reduce the rate of preterm delivery, but with elevated cervical mucus IL-8 cerclage may be harmful.

Pre-B-cell colony-enhancing factor is a secreted cytokine-like protein from the human amniotic epithelium

OBJECTIVE

The purpose of this study was to determine whether pre-B-cell colony-enhancing factor is a secreted cytokine in the human amnion and to study its chemotaxic and antiapoptotic properties.

STUDY DESIGN

Pre-B-cell colony-enhancing factor secretion was studied from amniotic epithelial-like WISH cells and primary amniotic epithelial cells that were seeded on squares of immobilon-P membrane and stimulated with lipopolysaccharide or tumor necrosis factor-alpha, respectively. The pre-B-cell colony-enhancing factor protein was detected both intracellularly and after secretion, as bound to the membrane, by immunostaining and densitometry. Medium and cell lysates that were obtained from WISH cells that were treated with lipopolysaccharide alone or together with a pre-B-cell colony-enhancing factor antisense oligonucleotide to block pre-B-cell colony-enhancing factor translation were also analyzed for secreted pre-B-cell colony-enhancing factor by Western blotting and densitometry. A chemotaxic effect of pre-B-cell colony-enhancing factor on human neutrophils was compared with the chemoattractants interleukin-8 and N-Formyl-Met-Leu-Phe methyl ester in a rapid fluorescence-based neutrophil migration assay. Apoptosis was induced in primary amniotic epithelial cells and fibroblasts by actinomycin D (1 microg/mL); the antiapoptotic effects of pre-B-cell colony-enhancing factor on early apoptosis were measured by the annexin V assay, and the late effects were determined by measurement of nuclear matrix protein in the media.

RESULTS

Treatment of amnion cells that adhered to immobilon-P membrane to induce the secretion of pre-B-cell colony-enhancing factor showed significantly (P<.05) more pre-B-cell colony-enhancing factor protein surrounding the cells compared with the controls. Although the addition of lipopolysaccharide to cultured WISH cells caused the secretion of pre-B-cell colony-enhancing factor into the medium, co-treatment with an antisense oligonucleotide to pre-B-cell colony-enhancing factor obliterated it. Analysis of the cell lysates showed no significant change, which suggests that most of the pre-B-cell colony-enhancing factor protein had been secreted. No significant chemotaxic effects of pre-B-cell colony-enhancing factor were observed; however, pre-B-cell colony-enhancing factor treatment (100 ng/mL), together with actinomycin D, cancelled the early induction of apoptosis, although there was a dose-dependent and significant late antiapoptotic effect on primary amnion epithelial cells (P<.001) and fibroblasts (P<.01).

CONCLUSION

Pre-B-cell colony-enhancing factor is a secreted protein from amniotic epithelial cells. Although it had no chemotaxic effects, it was antiapoptotic for both amniotic epithelial cells and fibroblasts and may protect these cells against apoptosis that is induced by chronic distension, labor, or infection.

Preventive effect of recombinant human lactoferrin in a rabbit preterm delivery model

OBJECTIVE

Lactoferrin, an iron-binding glycoprotein found in cervical mucus and amniotic fluid, plays a defensive role against mucosal infections. This study examined the effect of recombinant human lactoferrin on preterm delivery in a rabbit model.

STUDY DESIGN

Anesthetized rabbits were randomly assigned to receive either inoculation with Escherichia coli or saline solution and to receive treatment with or without recombinant human lactoferrin inserted into the cervix 2 hours before bacterial inoculation (condition A: saline + saline; condition B: E coli + saline; condition C: E coli + recombinant human lactoferrin). E coli , saline solution, and recombinant human lactoferrin were inserted into the cervix using a hysteroscope and a sterile polyethylene cannula. Fetus survival rate and days to delivery after inoculation were monitored and tumor necrosis factor-alpha concentrations were measured in maternal serum and amniotic fluid.

RESULTS

Fetus survival for conditions A, B, and C were 95.7%, 0%, and 32.6%, respectively, whereas pregnancy continuation was 7.00 +/- 0 days, 3.25 +/- 0.43 days, and 4.85 +/- 1.77 days, respectively.

CONCLUSION

Cervical recombinant human lactoferrin administration increased fetal survival and extended pregnancy. Lactoferrin has an anti-inflammatory action as well as an antibacterial action, suggesting that recombinant human lactoferrin has the potential to prevent preterm delivery originating from cervical infection in the clinical setting.

Relationship between cervical mucus interleukin-8 concentrations and vaginal bacteria in pregnancy

PROBLEM

High interleukin (IL)-8 concentration in cervical mucus in the second trimester is a risk factor for premature birth. We investigated the relationship between vaginal pathogens and IL-8 in cervical mucus.

METHOD OF STUDY

In 501 women with single pregnancy, vaginal secretions were cultured for bacteria and cervical mucus IL-8 concentrations were measured between 20 and 24 gestational weeks.

RESULTS

Lactobacillus species were detected in 56.0% of 84 subjects with high IL-8 (> or =377 ng/mL), significantly less often than in 417 subjects with IL-8 below 377 ng/mL (84.7%; P < 0.0001). Anaerobic pathogens were detected in 83.3% of high IL-8 subjects, significantly more often than in normal IL-8 subjects (43.9%; P < 0.0001). By multivariate analysis, cervical IL-8 was significantly high only in subjects without Lactobacillus species; they showed a significantly higher prematurity rate than Lactobacillus-positive subjects.

CONCLUSIONS

Absence of vaginal Lactobacilli was associated with increased cervical IL-8 and increased risk of premature delivery.