Diagnostic biomarkers of pro-inflammatory immune-mediated preterm birth

Characterisation of Mid-Gestation Amniotic Fluid Cytokine and Bacterial DNA Profiles in Relation to Pregnancy Outcome in a Small Australian Cohort

A well-established association exists between intrauterine bacteria and preterm birth. This study aimed to explore this further through documenting bacterial and cytokine profiles in Australian mid-gestation amniotic fluid samples from preterm and term births. Samples were collected during amniocenteses. DNA was extracted and the full-length 16S rRNA gene was amplified and sequenced. Levels of the cytokines IL-1β, IL-6, IL-10, TNF-α and MCP-1 were determined using the Milliplex MAGPIX system. Bacterial DNA profiles were low in diversity and richness, with no significant differences observed between term and preterm samples. No differences in the relative abundance of individual OTUs between samples were identified. IL-1β and TNF-α levels were significantly higher in samples containing reads mapping to Sphingomonas sp.; however, this result should be interpreted with caution as similar reads were also identified in extraction controls. IL-6 levels were significantly increased in samples with reads that mapped to Pelomonas sp., whilst TNF-α levels were elevated in fluid samples from pregnancies that subsequently delivered preterm. Bacterial DNA unlikely to have originated from extraction controls was identified in 20/31 (64.5%) mid-gestation amniotic fluid samples. Bacterial DNA profiles, however, were not predictive of preterm birth, and although cytokine levels were elevated in the presence of certain genera, the biological relevance of this remains unknown.

Serum cytokines in second trimester pregnancy and their relationship with spontaneous preterm births in the Ribeirão Preto and São Luiz cohorts

OBJECTIVE

To evaluate the association between second trimester plasma cytokine levels in asymptomatic pregnant women and preterm births (PTB) in an attempt to identify a possible predictor of preterm birth.

METHODS

The study design was a nested case-control study including women with singleton a gestational age between 20-25(+ 6) weeks from two Brazilian cities. The patients were interviewed, Venous blood samples were collected. The participants were again evaluated at birth. A total of 197 women with PTB comprised the case group. The control group was selected among term births (426 patients). Forty-one cytokines were compared between groups.

RESULTS

When only spontaneous PTB were analyzed, GRO, sCD40L and MCP-1 levels were lower in the case group (p < 0.05). Logarithmic transformation was performed for cytokines with discrepant results, which showed increased levels of IL-2 in the group of spontaneous PTB (p < 0.05). In both analyses, the incidence of maternal smoking and of a history of preterm delivery differed significantly between the case and control groups. In multivariate analysis, only serum GRO levels differed between the case and control groups.

CONCLUSION

Lower second trimester serum levels of GRO in asymptomatic women are associated with a larger number of PTB. This finding may reflect a deficient maternal inflammatory response.

Relationship between Platelet-to-Lymphocyte Ratio and Lymphocyte-to-Monocyte Ratio with Spontaneous Preterm Birth: A Systematic Review and Meta-analysis

Background

Spontaneous preterm birth is one of the most common pregnancy complications in obstetric clinical practice, and its etiology is complex. The problems of low survival and high morbidity rates of premature infants need to be solved urgently. The platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) are two novel biomarkers of inflammation, and several studies have linked PLR and LMR to spontaneous preterm birth. These systematic review and meta-analysis are aimed at analyzing the relationship between PLR and LMR in patients with spontaneous preterm birth to provide new ideas for the early prevention and treatment of spontaneous preterm births.

Methods

Cochrane Library, EMBASE, PubMed, and China National Knowledge Infrastructure databases were inspected to gather PLR and LMR in patients with spontaneous preterm birth, all from the database to February 2022. Interstudy heterogeneity was evaluated using Cochran's Q test and I 2 statistic. Differences in PLR and LMR between patients with spontaneous preterm birth and full-term controls were evaluated by computing standardized mean differences and 95% confidence intervals. Publication bias and sensitivity analyses were also performed.

Results

Nine studies were included in the meta-analysis based on the inclusion and exclusion criteria. The meta-analysis showed that serum PLR values were remarkably larger for patients with spontaneous preterm birth than for full-term controls (SMD = 0.49, 95% CI: 0.13 to 0.84, P = 0.007), whereas the difference between serum LMR in patients with spontaneous preterm birth and full-term controls was not statistically significant (SMD: 0.35, 95% CI: -0.18, 0.88, P = 0.199). The results of Begg's and Egger's tests revealed that the publication bias of the meta-analysis was not significant. The outcomes of the sensitivity analysis showed that the individual studies did not influence the meta-analysis results.

Conclusions

Current evidence shows that PLR is strongly associated with spontaneous preterm birth, whereas LMR is not. PLR has a certain clinical value in diagnosing and treating spontaneous preterm births, and our research will provide strong theoretical support for clinical work. In the future, it will be necessary to further explore the reasons for the increased PLR in the serum of patients with spontaneous preterm birth and other mechanisms inducing spontaneous preterm birth.

Release of HMGB1 and Toll-like Receptors 2, 4, and 9 Signaling Are Modulated by Bifidobacterium animalis subsp. lactis BB-12 and Salmonella Typhimurium in a Gnotobiotic Piglet Model of Preterm Infants

Gnotobiotic (GN) animals with defined microbiota allow us to study host-microbiota and microbiota-microbiota interferences. Preterm germ-free (GF) piglets were mono-associated with probiotic Bifidobacterium animalis subsp. lactis BB-12 (BB12) to ameliorate/prevent the consequences of infection with the Salmonella Typhimurium strain LT2 (LT2). Goblet cell density; expression of Toll-like receptors (TLRs) 2, 4, and 9; high mobility group box 1 (HMGB1); interleukin (IL)-6; and IL-12/23p40 were analyzed to evaluate the possible modulatory effect of BB12. BB12 prevented an LT2-induced decrease of goblet cell density in the colon. TLRs signaling modified by LT2 was not influenced by the previous association with BB12. The expression of HMGB1, IL-6, and IL12/23p40 in the jejunum, ileum, and colon and their levels in plasma were all decreased by BB12, but these changes were not statistically significant. In the colon, differences in HMGB1 distribution between the GF and LT2 piglet groups were observed. In conclusion, the mono-association of GF piglets with BB12 prior to LT2 infection partially ameliorated the inflammatory response to LT2 infection.

Long Noncoding RNA LIFR-AS1: A New Player in Human Cancers

Emerging evidence has indicated that aberrantly expressed long noncoding RNAs (lncRNAs) play a vital role in various biological processes associated with tumorigenesis. Leukemia inhibitory factor receptor antisense RNA1 (LIFR-AS1) is a recently identified lncRNA transcribed in an antisense manner from the LIFR gene located on human chromosome 5p13.1. LIFR-AS1 regulates tumor proliferation, migration, invasion, apoptosis, and drug resistance through different mechanisms. Its expression level is related to the clinicopathological characteristics of tumors and plays a key role in tumor occurrence and development. In this review, we summarize the role of LIFR-AS1 in the development and progression of different cancers and highlight the potential for LIFR-AS1 to serve as a biomarker and therapeutic target for a variety of human cancers.

IL-37 Exerts Anti-Inflammatory Effects in Fetal Membranes of Spontaneous Preterm Birth via the NF-κB and IL-6/STAT3 Signaling Pathway

Spontaneous preterm birth (sPTB), defined as delivery before 37 weeks of gestation, is thought to be a multifactorial syndrome. However, the inflammatory imbalance at the maternal-fetal interface promotes excessive secretion of inflammatory factors and induces apoptosis and degradation of the extracellular matrix (ECM), which can subsequently lead to preterm birth. As an anti-inflammatory molecule in the IL-1 family, interleukin-37 (IL-37) mainly plays an inhibiting role in a variety of inflammatory diseases. However, as a typical inflammatory disease, no previous studies have been carried out to explore the role of IL-37 in sPTB. In this study, a series of molecular biological experiments were performed in clinical samples and human amniotic epithelial cell line (Wistar Institute Susan Hayflick (WISH)) to investigate the deficiency role of IL-37 and the potential mechanism. Firstly, the results indicated that the expression of IL-37 in human peripheral plasma and fetal membranes was significantly decreased in the sPTB group. Afterward, it is proved that IL-37 could significantly suppress the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in WISH cells. Simultaneously, once silence IL-37, LPS-induced apoptosis and activity of matrix metalloproteinases (MMPs) 2 and 9 were significantly increased. In addition, the western blot data showed that IL-37 performed its biological effects by inhibiting the NF-κB and IL-6/STAT3 pathway. In conclusion, our results suggest that IL-37 limits excessive inflammation and subsequently inhibits ECM remodeling and apoptosis through the NF-κB and IL-6/STAT3 signaling pathway in the fetal membranes.

Early pregnancy immune profile and preterm birth classified according to uteroplacental lesions

INTRODUCTION

Preterm birth is a heterogeneous phenotype, with placental abnormalities underlying many cases. The etiology of preterm births that occur in the absence of placental abnormalities, however, remain enigmatic and we considered that early pregnancy biomarkers may provide clues.

METHODS

Women from a hospital-based cohort (2008-2012, n = 397) were randomly selected within 6 strata of term and preterm birth with and without placental decidual vasculopathy (arteriopathy), intrauterine inflammation/infection (acute chorioamnionitis), or no lesions. Lipids and inflammatory markers were analyzed in first trimester samples (12.5 ± 0.6 weeks) and related to outcome groups (referent, term births with no lesions). Factor analysis then clustered analytes and related these to preterm birth groups, adjusted for covariates and stratified by pre-pregnancy obesity.

RESULTS

Three biomarker patterns were identified. Immune activation cytokines (33% of the variance) were associated with preterm birth with no lesions (aOR 1.5, 95%CI 1.1-2.1), particularly among obese women. In contrast, inflammatory chemokines (9% of variance) were associated with term and preterm vasculopathy among non-obese women (aOR 2.6 [1.3, 4.7] and 2.0 [1.1, 3.0], respectively).

DISCUSSION

The early pregnancy maternal immune profile is related to preterm births classified according to placental lesions, and these associations vary according to obesity status.

Amniotic fluid proteomic signatures of cervical insufficiency and their association with length of latency

PROBLEM

Cervical insufficiency is a precursor of preterm birth. Treatment with emergency cervical cerclage is contraindicated in the presence of intra-amniotic infection. Detecting infection with Gram stain and culture of amniotic fluid lacks sensitivity. Proteomic profiling of amniotic fluid in cervical insufficiency may help identify pregnancies best suited for emergency cerclage.

METHOD OF STUDY

Thirty-two pregnant women underwent amniocentesis for routine genetic testing (n = 22) or after diagnosis of cervical insufficiency (n = 10). The proteomic profiles of the amniotic fluid samples were compared in a cross-sectional fashion, including sub-analyses of women with cervical insufficiency and latency periods of <1 week and >1 week post-diagnosis.

RESULTS

Mean gestational age at diagnosis of cervical insufficiency was 21.4 weeks (95% CI 20.6-22.1). Proteomic analysis yielded 40 (7.2%, P < 0.05) differentially expressed proteins between women with delivery <1 week (n = 6) vs. >1 week (n = 4). Women who delivered <1 week had activated inflammatory response (z = 2.3, P = 6.71E-09), chemotaxis of immune cells (z = 2.9, P = 2.01E-08), and inhibited bacterial growth (z = -2.2, P = 5.82E-05). A multivariate model of eight biomarkers positively associated with cases of <1 week latency and distinguished cases from controls (97.8%, cross-validation accuracy 92.7%, P = 0.0009).

CONCLUSION

In this pilot study, significant differences in the amniotic fluid proteomic profiles in cases of cervical insufficiency compared to genetic amniocentesis were observed. Proteomic signatures were predictive of achieving latency > 1 week after diagnosis of cervical insufficiency. These preliminary findings suggest that proteomic analysis may be of value in predicting outcome following cervical insufficiency and warrants further validation in larger studies.

Association of Colecalciferol, Ferritin, and Anemia among Pregnant Women: Result from Cohort Study on Vitamin D Status and Its Impact during Pregnancy and Childhood in Indonesia

Studies had shown that iron-cycling was disturbed by inflammatory process through the role of hepcidin. Pregnancy is characterized by shifts of interleukin. Our objective was to determine if 25(OH) vitamin D (colecalciferol) status was associated with ferritin, anemia, and its changes during pregnancy. Method. A cohort study was done in 4 cities in West Java, Indonesia, beginning in July 2016. Subjects were followed up until third trimester. Examinations included were maternal ferritin, colecalciferol, and haemoglobin level. Result. 191 (95.5%) subjects had low colecalciferol, and 151 (75.5%) among them were at deficient state. Anemia is found in 15 (7.5%) subjects, much lower than previous report. Proportion of anemia increased by trimester among women with colecalciferol deficiency. Ferritin status and prepregnancy body mass index in the first trimester were correlated with anemia (r = 0.147, p = 0.038 and r = -0.56, p = 0.03). Anemia in the second trimester was strongly correlated with anemia in the third trimester (r = 0.676, p < 0.01). Conclusion. Our study showed that the state of colecalciferol was not associated with either ferritin state or anemia, but proportion of anemia tends to increase by trimester in the colecalciferol deficient subjects.

Intrauterine infection, immune system and premature birth

Preterm birth accounts for nearly one million deaths among children under five years of age, and although its etiopathogenesis is not fully elucidated, ascending intrauterine infection and fetal inflammatory response seem to be the main triggers. The intense inflammatory response mediated by IL-1β, TNF-α, PAF, IFN-γ and IL-6, PGE₂ and MMP-1 and MMP-9 causes fetal membrane damage and rupture, increased uterine contractions and biochemical and structural changes in the cervix. Furthermore, preterm neonates have deficient innate and adaptive immune responses characterized by reduced levels of IgG, opsonization and phagocytosis, as well as increased activation of Th1 cells in relation to Th2 cells. Therefore, this triad is favors the occurrence of neonatal complications, such as respiratory distress syndrome, necrotizing enterocolitis, retinopathy of prematurity and bronchopulmonary dysplasia. Due to serious maternal and child health complications of intrauterine infection, several studies have tried to identify biomarkers for the early diagnosis of this entity. This literature review aims to discuss the main scientific findings regarding the association between ascending intrauterine infection, immune system and preterm birth.

Early- or mid-trimester amniocentesis biomarkers for predicting preterm delivery: a meta-analysis

OBJECTIVE

To determine the value of early- or mid-trimester amniotic fluid levels of interleukin-6 (IL-6), matrix metalloproteinase-8 (MMP-8), and glucose for predicting preterm delivery.

METHODS

Randomized controlled trials and two-arm prospective, retrospective, cohorts, and case-controlled studies in which patients received early- or mid-trimester amniocentesis for karyotyping, and biomarker testing of the amniotic fluid was performed and delivery data were available were included in the analysis.

RESULTS

Outcome measures were the associations of amniotic fluid IL-6, MMP-8, and glucose levels with preterm delivery. Differences in means with 95% confidence intervals (CIs) were calculated. Of 288 articles identified, 14 were included in the meta-analysis with a total of 675 patients who had preterm birth and 2518 patients who had term births. The preterm-delivery group had significantly higher amniotic fluid IL-6 and MMP-8 levels, and a significantly lower glucose level than the term delivery group (IL-6: difference in means = 0.32, 95% CI: 0.22-0.43, p < 0.001; MMP-8: difference in means = 4.47, 95% CI: 0.83-8.11), p = 0.016; glucose: difference in means = -5.22, 95% CI: -8.19 to -2.26, p = 0.001) Conclusion: Early- or mid-trimester amniotic fluid IL-6, MMP-8, and glucose levels are useful for predicting the risk of preterm delivery. KEY MESSAGES Median amniotic fluid ferritin and IL-6 levels, and mean amniotic fluid ALP levels were higher in the preterm group. The preterm-delivery group had significantly higher amniotic fluid IL-6 and MMP-8 levels, and a significantly lower glucose level than the term-delivery group.

[Association between tumor necrosis factor-α G-308A polymorphisms and genetic susceptibility to spontaneous preterm birth]

OBJECTIVE

To study the association between tumor necrosis factor-α (TNF-α) G-308A polymorphisms and genetic susceptibility to spontaneous preterm birth (SPTB).

METHODS

The case group enrolled 753 SPTB infants and the control group included 681 term infants. TNF-α G-308A polymorphisms were genotyped using Sequenom MassARRAY®SNP.

RESULTS

The frequencies of the allele (G and A) in the case and control groups were not significantly different (P=0.35). The frequencies of the genotypes (GG, GA and AA) in the case and control groups were not significantly different (P=0.64). The logistic regression analysis found that TNF-α G-308A was not associated with genetic susceptibility to SPTB (OR=0.85; 95%CI: 0.61-1.19; P=0.35).

CONCLUSIONS

There is no association between the polymorphisms of TNF-α G-308A and the genetic susceptibility to SPTB.

[Association between interleukin-1β C+3953T and genetic susceptibility to spontaneous preterm birth: a case-control study]

OBJECTIVE

To study the association between interleukin-1β (IL-1β) C+3953T and genetic susceptibility to spontaneous preterm birth (SPTB).

METHODS

In this case-control study, 753 SPTB neonates were enrolled in the case group and 681 full-term neonates were enrolled in the control group. The latest Sequenom MassARRAY®SNP detection technique was used for the typing of single nucleotide polymorphisms (SNP) of IL-1β C+3953T.

RESULTS

Compared with those carrying CC genotype of IL-1β C+3953T, the neonates who carried at least one T allele (CT+TT genotype) had significantly increased risks of SPTB, SPTB complicated by premature rupture of membranes, and mild preterm birth.

CONCLUSIONS

In the Chinese population, IL-1β C+3953T has significant genetic association with an increased risk of SPTB. The identification of this SNP helps to prevent SPTB and clarify the causes and pathogenesis of SPTB.

Combined in utero hypoxia-ischemia and lipopolysaccharide administration in rats induces chorioamnionitis and a fetal inflammatory response syndrome

INTRODUCTION

Preterm birth is a major cause of infant morbidity and long-term disability, and is associated with numerous central nervous system (CNS) deficits. Infants exposed to intrauterine inflammation, specifically chorioamnionitis, are at risk for very early preterm birth and neurological complications including cerebral palsy, epilepsy, and behavioral and cognitive deficits. However, placenta-brain axis abnormalities and their relationship to subsequent permanent CNS injury remain poorly defined.

METHODS

Intrauterine injury was induced in rats on embryonic day 18 (E18) by transient systemic hypoxia-ischemia (TSHI) and intra-amniotic lipopolysaccharide (LPS) injection. Placenta, brain and serum were collected from E19 to postnatal day 0 (P0). Histology, TUNEL staining, western blot and multiplex immunoassays were used to quantify placental and brain abnormalities, and fetal serum cytokine levels.

RESULTS

Prenatal TSHI + LPS caused acute and subacute placental injury hallmarked by inflammatory infiltrate, edema, hemorrhage and cell death along with placental increases in IL-1β and TNFα. TSHI + LPS increased a diverse array of circulating inflammatory proteins including IL-1β, TNFα, IL-6, IL-10, IL-4, IFNγ and CXCL1, both immediately after TSHI + LPS and in live born pups. CNS inflammation was characterized by increased CXCL1.

DISCUSSION

Prenatal TSHI + LPS in rats induces placental injury and inflammation histologically consistent with chorioamnionitis, concomitant with elevated serum and CNS pro-inflammatory cytokines. This model accurately recapitulates key pathophysiological processes observed in extremely preterm infants including placental, fetal, and CNS inflammation. Further investigation into the mechanism of CNS injury following chorioamnionitis and the placental-brain axis will guide the use of future interventions.

Expression of CCL22 and Infiltration by Regulatory T Cells are Increased in the Decidua of Human Miscarriage Placentas

PROBLEM

Regulatory T cells (Treg) are a T-cell subpopulation with suppressive capacities, specifically attracted by CCL22. We aimed to investigate whether CCL22 is expressed in human placentas and whether its presence, together with Treg infiltration, is associated with miscarriage conditions.

METHOD OF STUDY

Paraffin samples were stained for CCL22 and for the Treg-specific transcription factor FoxP3. Expression levels were evaluated in a semi-quantitative manner. Double immunofluorescence was used for the identification of CCL22-producing cells.

RESULTS

In all placentas, trophoblasts expressed CCL22. Interestingly, expression in the decidua was only observed in miscarriage conditions. Maternal stromal cells expressed CCL22. Correlation with a higher presence of Treg in the decidua of abortive tissues was observed.

CONCLUSION

Our results demonstrate that CCL22 is expressed in human placenta. Decidual expression was only observed in miscarriage conditions and correlates with Treg infiltration. Thus, CCL22 plays a role in human pregnancy and may occur as a negative feedback response to pro-inflammatory events during miscarriage conditions.

Second trimester amniotic fluid cytokine concentrations, Ureaplasma sp. colonisation status and sexual activity as predictors of preterm birth in Chinese and Australian women

BACKGROUND

This study tested if second trimester amniotic fluid cytokine levels, Ureaplasma sp. colonisation and sexual activity predict preterm birth and explain the differential preterm birth rates in Chinese compared to Australian women.

METHODS

Amniotic fluid was collected by amniocentesis (Chinese 480, Australian 492). Cytokines were measured by multiplex assay and Ureaplasma sp. DNA was detected by PCR analysis. Lifestyle factors, including history of smoking and sexual activity during pregnancy, were obtained through completion of questionnaires upon recruitment to the study.

RESULTS

Inflammatory cytokine concentrations were poorly predictive of preterm birth. Ureaplasma sp. was detected in two of the Chinese pregnancies and none from Australia. Sexual activity was less frequent in Chinese, and was not associated with preterm birth or amniotic fluid findings in either population.

DISCUSSION

Second trimester amniocentesis for measurement of inflammatory markers and Ureaplasma sp. DNA was not indicative of risk of preterm birth, at least in these populations. The lower rate of preterm birth in China was not explained by differences in amniotic fluid inflammatory markers, Ureaplasma sp. colonisation, or sexual activity.

Changes in maternal blood inflammatory markers as a predictor of chorioamnionitis: a prospective multicenter study

PROBLEM

To evaluate the inflammatory pattern in maternal circulation from women with preterm premature rupture of membranes (PPROM) considering the occurrence of histologically confirmed chorioamnionitis (HCA).

METHOD OF STUDY

A prospective study was conducted in 121 women with PPROM between 24 and 34 + 0 weeks of gestation. Association between white blood cells (WBC) count, plasma CRP, IL-6, MCP-1 and IP-10 levels, and HCA was assessed.

RESULTS

The rate of HCA was 44.7% (54/121). During the 5 days preceding delivery, median CRP, WBC, and IL-6 levels were significantly higher in the HCA than in no-HCA group (P < 0.001). Variations in IL-6, IP-10 levels, during the 24-72 hr before delivery, were predictors of the occurrence of HCA, but the diagnostic accuracy was low [Receiver Operating Characterictic (ROC) curve, area under the curve (AUC) = 0.56].

CONCLUSION

An increase in IL-6, CRP, IP-10 maternal plasma levels was confirmed in PPROM women with HCA. Longitudinal follow-up of these markers did not add valuable information regarding HCA.

The citrus flavone nobiletin reduces pro-inflammatory and pro-labour mediators in fetal membranes and myometrium: implications for preterm birth

Spontaneous preterm birth is the leading cause of infant death and of neurological disabilities in survivors. A significant proportion of spontaneous preterm births are associated with infection. Infection activates inflammation which induces a cascade of events that leads to myometrial contractions and rupture of fetal membranes. In non-gestational tissues, the citrus flavone nobiletin has been shown to exert potent anti-inflammatory properties. Thus, in this study, we sought to determine the effect of nobiletin on pro-inflammatory mediators in human fetal membranes and myometrium. Human fetal membranes and myometrium were treated with bacterial endotoxin lipopolysaccharide (LPS) in the absence or presence of nobiletin. In addition, the effect of nobiletin in fetal membranes taken from spontaneous preterm deliveries with and without infection (i.e. histological chorioamnionitis) was also examined. In human fetal membranes and myometrium, nobiletin significantly decreased LPS-stimulated expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-8) and MMP-9 expression and pro-MMP-9 secretion. Additionally, nobiletin significantly decreased COX-2 expression and subsequent prostaglandin (PG) E₂ production. Notably, nobiletin was also able to reduce the expression and production of pro-inflammatory cytokines and MMP-9 in fetal membranes taken from women after spontaneous preterm birth. In conclusion, our study demonstrates that nobiletin can reduce infection-induced pro-inflammatory mediators in human fetal membranes and myometrium. These in vitro studies further support the increasing volume and quality of evidence that high fruit and vegetable intake in pregnancy is associated with a decreased risk of adverse pregnancy outcomes.

Probiotic Lactobacillus rhamnosus GR-1 supernatant prevents lipopolysaccharide-induced preterm birth and reduces inflammation in pregnant CD-1 mice

OBJECTIVE

The objective of this study was to determine the effect of probiotic Lactobacillus rhamnosus GR-1 supernatant (GR-1 SN) on lipopolysaccharide-induced preterm birth (PTB) and outputs of cytokines, chemokines, and progesterone in pregnant CD-1 mice.

STUDY DESIGN

We compared PTB rates after intrauterine injection of lipopolysaccharide with and without previous GR-1 SN treatment. Cytokines and chemokines in the maternal plasma, myometrium, placenta, and amniotic fluid were examined with multiplex assay, and circulating maternal progesterone was measured with enzyme-linked immunoassay. Statistical significance was assessed with 2-tailed 1-way analysis of variance or analysis of variance on ranks. Fetal sex ratios in mice that delivered preterm were compared with those that delivered at term after lipopolysaccharide and GR-1 SN treatments.

RESULTS

GR-1 SN reduced lipopolysaccharide-induced PTB by 43%. GR-1 SN significantly decreased the lipopolysaccharide-induced production of interleukin (IL)-1β, -6, and -12p40, tumor necrosis factor-α, CCL4, and CCL5 in maternal plasma; IL-6, -12p70, -17, and -13 and tumor necrosis factor-α in myometrium; IL-6, -12p70, and -17 in placenta; and IL-6, tumor necrosis factor-α, CCL3, and CCL4 in amniotic fluid. Maternal plasma progesterone was reduced significantly after lipopolysaccharide injection with and without GR-1 SN pretreatment. There was no difference in fetal sex ratios between mice that delivered preterm and those that did not after lipopolysaccharide and GR-1 SN treatments.

CONCLUSION

The supernatant of probiotic L rhamnosus GR-1 attenuated lipopolysaccharide-induced inflammation and PTB in vivo. GR-1 SN may confer therapeutic benefits in the prevention of infection-associated PTB by controlling systemic and intrauterine inflammation.

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.

The effects of anemia on pregnancy outcome in patients with pyelonephritis

Objective. Pyelonephritis is a common infectious morbidity of pregnancy. Though anemia is commonly associated with pyelonephritis, there are little data describing the effect of pyelonephritis with anemia on pregnancy outcomes. The purpose of this study was to further assess the association of anemia with infectious morbidity and pregnancy complications among women with pyelonephritis. Study Design. We conducted a retrospective cohort study of pregnant women admitted to Duke University Hospital between July 2006 and May 2012 with pyelonephritis. Demographic, laboratory, and clinical data from the subject's pregnancy and hospitalizations were analyzed. Patients with pyelonephritis and anemia (a hematocrit < 32) were compared to those without anemia. Descriptive statistics were used to compare the two groups. Results. 114 pregnant women were admitted with pyelonephritis and 45 (39.5%) had anemia on admission. There was no significant difference in age, race, preexisting medical conditions, or urine bacterial species between patients with anemia and those without. Women with anemia were more likely to deliver preterm (OR 3.3 (95% CI 1.07, 11.4), P = 0.04). When controlling for race and history of preterm delivery, women with anemia continued to have increased odds of preterm birth (OR 6.0, CI 1.4, 35, P = 0.012). Conclusion. Women with pyelonephritis and anemia are at increased risk for preterm delivery.

Identification of biomarkers for preterm delivery in mid-trimester amniotic fluid

OBJECTIVE

We investigated whether the level of vascular endothelial growth factor (VEGF) and inflammatory markers in mid-trimester amniotic fluid have predictive value for spontaneous preterm birth in singleton pregnancy.

METHOD

Our subjects were 72 pregnant women who were undertaken with amniocentesis from 16 to 19 weeks of gestation. 36 cases were women with preterm delivery, and other 36 cases were matched women with full-term delivery. Stored amniotic fluid was investigated after the delivery. The levels of matrix metalloproteinases-8 (MMP-8), interleukin-6 (IL-6), C-reactive protein (CRP), and VEGF were measured by enzyme-linked immunosorbent assay (ELISA) and Western blot.

RESULTS

The levels of MMP-8 and IL-6 in preterm group were significantly higher than control group (5.76 ± 1.53 ng/ml vs 4.89 ± 1.77 ng/ml and 170.54 ± 55.69 pg/ml vs 141.92 ± 57.21 pg/ml, respectively) (p < 0.05). In terms of VEGF, the levels were elevated in preterm group (30.76 ± 4.06 pg/ml vs 22.36 ± 7.03 pg/ml) (p < 0.05).

CONCLUSION

This study suggests that elevated levels of IL-6 and MMP-8 in amniotic fluid at mid-trimester are predictive of preterm delivery, and that VEGF which is representative of angiogenesis can be a new and useful predictor of preterm delivery.