Cytokines, pregnancy, and bacterial vaginosis: comparison of levels of cervical cytokines in pregnant and nonpregnant women with bacterial vaginosis

Microbiome and pregnancy: focus on microbial dysbiosis coupled with maternal obesity

Obesity is becoming a worldwide pandemic with over one billion people affected. Of women in the United States, who are of childbearing age, two-thirds of them are considered overweight/obese. Offspring of women with obesity have a greater likelihood of developing cardiometabolic disease later in life, therefore making obesity a transgenerational issue. Emerging topics such as maternal microbial dysbiosis with altered levels of bacterial phyla and maternal obesity programming offspring cardiometabolic disease are a novel area of research discussed in this review. In the authors' opinion, beneficial therapeutics will be developed from knowledge of bacterial-host interactions at the most specific level possible. Although there is an abundance of obesity-related microbiome research, it is not concise, readily available, nor easy to interpret at this time. This review details the current knowledge regarding the relationship between obesity and the gut microbiome, with an emphasis on maternal obesity.

Immunometabolic and potential tumor-promoting changes in 3D cervical cell models infected with bacterial vaginosis-associated bacteria

Specific bacteria of the human microbiome influence carcinogenesis at diverse anatomical sites. Bacterial vaginosis (BV) is the most common vaginal disorder in premenopausal women that is associated with gynecologic sequelae, including cervical cancer. BV-associated microorganisms, such as Fusobacterium, Lancefieldella, Peptoniphilus, and Porphyromonas have been associated with gynecologic and other cancers, though the pro-oncogenic mechanisms employed by these bacteria are poorly understood. Here, we integrated a multi-omics approach with our three-dimensional (3-D) cervical epithelial cell culture model to investigate how understudied BV-associated bacteria linked to gynecologic neoplasia influence hallmarks of cancer in vitro. Lancefieldella parvulum and Peptoniphilus lacrimalis elicited robust proinflammatory responses in 3-D cervical cells. Fusobacterium nucleatum and Fusobacterium gonidiaformans modulated metabolic hallmarks of cancer corresponding to accumulation of 2-hydroxyglutarate, pro-inflammatory lipids, and signs of oxidative stress and genotoxic hydrogen sulfide. This study provides mechanistic insights into how gynecologic cancer-associated bacteria might facilitate a tumor-promoting microenvironment in the human cervix.

HIV-associated vaginal microbiome and inflammation predict spontaneous preterm birth in Zambia

A Lactobacillus-deficient, anaerobe-rich vaginal microbiome has been associated with local inflammation and spontaneous preterm birth (sPTB), but few studies have assessed this association in the setting of HIV. We performed metagenomic sequencing and inflammatory marker assays on vaginal swabs collected in pregnancy. We grouped samples into 7 metagenomic clusters (mgClust) using the non-redundant VIRGO catalogue, and derived inflammatory scores by factor analysis. Of 221 participants, median Shannon diversity index (SDI) was highest in HIV+ with detectable viral load (1.31, IQR: 0.85–1.66; p < 0.001) and HIV+ with undetectable virus (1.17, IQR: 0.51–1.66; p = 0.01) compared to HIV− (0.74, IQR: 0.35–1.26). Inflammatory scores positively correlated with SDI (+ 0.66, 95%CI 0.28, 1.03; p = 0.001), highest among anaerobe-rich mgClust2–mgClust6. HIV was associated with predominance of anaerobe-rich mgClust5 (17% vs. 6%; p = 0.02) and mgClust6 (27% vs. 11%; p = 0.002). Relative abundance of a novel Gardnerella metagenomic subspecies > 50% predicted sPTB (RR 2.6; 95%CI: 1.1, 6.4) and was higher in HIV+ (23% vs. 10%; p = 0.001). A novel Gardnerella metagenomic subspecies more abundant in women with HIV predicted sPTB. The risk of sPTB among women with HIV may be mediated by the vaginal microbiome and inflammation, suggesting potential targets for prevention.

Lactobacillus-Depleted Vaginal Microbiota in Pregnant Women Living With HIV-1 Infection Are Associated With Increased Local Inflammation and Preterm Birth

Background

Pregnant women living with HIV-1 infection (PWLWH) have an elevated risk of preterm birth (PTB) of unknown aetiology, which remains after successful suppression of HIV. Women at high risk for HIV have a common bacterial profile which has been associated with poor birth outcomes. We set out to explore factors associated with gestational age at delivery of PWLWH in a UK population.

Methods

Prospective study of PWLWH (n = 53) in whom the vaginal microbiota and cervicovaginal cytokine milieu were assessed using metataxonomics and multiplexed immunoassays, respectively. Cross-sectional characterisation of vaginal microbiota in PWLWH were compared with 22 HIV uninfected pregnant women (HUPW) at a similar second trimester timepoint. Within PWLWH the relationships between bacterial composition, inflammatory response, and gestational age at delivery were explored.

Findings

There was a high rate of PTB among PWLWH (12%). In the second trimester the vaginal microbiota was more diverse in PWLWH than in HUPW (Inverse Simpson Index, p = 0.0004 and Species Observed, p = 0.009). PWLWH had a lower prevalence of L. crispatus dominant vaginal microbiota group (VMB I, 15 vs 54%) than HUPW and higher prevalence of L. iners dominant (VMB III, 36 vs 9% and VMB IIIB, 15 vs 5%) and mixed anaerobes (VMB IV, 21 vs 0%). Across the second and third trimesters in PWLWH, VMB III/IIIB and IV were associated with PTB and with increased local inflammation [cervicovaginal fluid (CVF) cytokine concentrations in upper quartile]. High bacterial diversity and anaerobic bacterial abundance were also associated with CVF pro-inflammatory cytokines, most notably IL-1β.

Interpretation

There is an association between local inflammation, vaginal dysbiosis and PTB in PWLWH. Understanding the potential of antiretroviral therapies to influence this cascade will be important to improve birth outcomes in this population.

The Cervicovaginal Mucus Barrier

Preterm births are a global health priority that affects 15 million babies every year worldwide. There are no effective prognostic and therapeutic strategies relating to preterm delivery, but uterine infections appear to be a major cause. The vaginal epithelium is covered by the cervicovaginal mucus, which is essential to health because of its direct involvement in reproduction and functions as a selective barrier by sheltering the beneficial lactobacilli while helping to clear pathogens. During pregnancy, the cervical canal is sealed with a cervical mucus plug that prevents the vaginal flora from ascending toward the uterine compartment, which protects the fetus from pathogens. Abnormalities of the cervical mucus plug and bacterial vaginosis are associated with a higher risk of preterm delivery. This review addresses the current understanding of the cervicovaginal mucus and the cervical mucus plug and their interactions with the microbial communities in both the physiological state and bacterial vaginosis, with a focus on gel-forming mucins. We also review the current state of knowledge of gel-forming mucins contained in mouse cervicovaginal mucus and the mouse models used to study bacterial vaginosis.

Elevation of cervical C-X-C motif chemokine ligand 10 levels is associated with HIV-1 acquisition in pregnant and postpartum women

OBJECTIVE

To evaluate the relationship between cervical cytokine/chemokine concentrations and HIV-1 acquisition in peripartum Kenyan women.

DESIGN

Nested case-control study.

METHODS

Women participating in a prospective study of peripartum HIV acquisition in Kenya (the Mama Salama Study), were tested for HIV-1 at 1-3 month intervals during pregnancy and through 9 months postpartum. Cases positive for HIV-1 RNA during follow-up (N = 14), were matched 3 : 1 with HIV-negative controls (N = 42) based on age, marital status, partner HIV-1 status, transactional sex, and timing of cervical swab collection. Concentrations of five cytokines (IL-1β, IL-6, IL-10, IFNγ, and TNFα) and four chemokines (IL-8, C-X-C motif chemokine ligand 10 (CXCL10), macrophage inflammatory protein-1 α, and macrophage inflammatory protein-1 β) were measured from cervical swabs collected at the visit prior to HIV-1 diagnosis (cases) or matched gestational/postpartum time (controls). Cytokine/chemokine concentrations were compared between cases and controls using Wilcoxon rank-sum tests. Principal component analysis was used to create a summary score for closely correlated cytokines/chemokines. Associations with HIV-1 acquisition were analyzed using conditional logistic regression. Path analysis was used to evaluate hypothesized relationships between CXCL10, vaginal washing, Nugent score, and HIV-1 acquisition.

RESULTS

Conditional logistic regression analysis demonstrated an association between increased concentrations of CXCL10 and HIV-1 acquisition (odds ratio = 1.74, 95% confidence interval 1.04, 2.93; P = 0.034). Path analysis confirmed a positive independent association between higher concentrations of CXCL10 and HIV-1 acquisition (path coefficient = 0.37, 95% confidence interval 0.15, 0.59; P < 0.001).

CONCLUSION

HIV-1 acquisition was associated with increased cervical concentrations of CXCL10 in pregnant and postpartum women.

PREVALENCE OF POTENTIALLY PATHOGENIC MICROBIOLOGICAL AGENTS IN VAGINAL EXUDATES OF ASYMPTOMATIC PREGNANT WOMEN, BARRANQUILLA, COLOMBIA, 2014-2015

OBJECTIVE

To determine the prevalence of potentially pathogenic microbiological agents in vaginal exudates in a sample of asymptomatic pregnant women in the Department of Atlantico, Colombia.

METHODS

Descriptive cross-sectional study of a sample of asymptomatic pregnant women who attended a private primary healthcare institution in Barranquilla, Colombia, between 2014 and 2015. Pregnant women having received antimicrobial treatment within the last 30 days, with vaginal bleeding, mental disability or immunosuppression, were excluded. Consecutive sampling was performed. The prevalence of colonization time by some of the microbiological agents as well as specific prevalence were estimated: number of women with infection by agent type/number of women at risk assessed.

RESULTS

Overall prevalence was 24.8% (56/226); 55.4% (31/56) was due to vaginitis causal agents, and 44.6% (25/56) to vaginosis. The specific prevalence by type of pathogen, 13.3% (30/226) was vaginitis due to colonization by Candida spp. and 0.4% (1/226) was vaginitis due to T. vaginalis. Bacterial vaginosis (BV) was found in 8.0% (18/226).

CONCLUSIONS

Substantial colonization of the lower genital tract by potentially pathogenic germs is found in pregnant women between 35 and 37 weeks of gestation. Further studies are required in order to determine the benefit of population screening in terms of avoiding poor maternal and perinatal out- comes, and the impact on the resulting overcosts.

Distinct patterns of microbial metabolic fingerprints in sows and their offspring: a pilot study

Microbial metabolism and growth in the intestinal tract depend on the composition of substrates present in the digesta and their ability to be metabolised by the microorganisms. The aim of this pilot study was to characterise potential hindgut microbial activity during perinatal period in sows and their offspring. Rectal samples from three sows (1-3 weeks before and after birth) and three of their piglets (1-5 weeks after birth), were subjected to assays using BIOLOG GEN III microplates to produce metabolic fingerprints for each animal. The number of metabolised substrates of the sow hindgut microbiota was stable during the pregnancy and lactation periods, as assessed by the richness index. In piglets, the richness was stable during the suckling period and at beginning of weaning, however, it decreased when the piglets were 5 weeks old (P ≤ 0.05). Analysis of associations between the sows and the piglets and the microbial metabolic potential showed that microbial metabolism was strongly associated with the catabolism of carbohydrates especially in sows. Only 5-week-old weaned piglets clustered together with the sows regarding the microbial catabolism of substrates, but not suckling piglets. The association analyses clustered all the piglets in two groups distinctive for litter. The analysis of metabolic fingerprints via microbial growth with different substrates can be useful to positively influence microbial community function such as selectively enhancing desirable active microbial populations to benefit health of the gut and the animal.

B S, H.S A, Kabbashi AS. Cytokines Level (Il8 and Il17) in Pregnant Women with Toxoplasmosis in Khartoum State

Toxoplasmosis is one of the most important zoonotic diseases worldwide caused by Toxoplasma gondii that leads to abortion or hydrocephalus during pregnancy. It’s a comparative cross-sectional one designed to assess immunoglobulins and cytokines in pregnant women. A total of 300 venous blood samples were collected from each pregnant woman and centrifuged to obtain serum. Patient’s information was recorded in a questionnaire previously designed for the purpose of analysis. In addition, 40 uninfected women were enrolled in the study as control group to assess the level of IL8 and IL17 cytokines. The overall seropositive rate of Toxoplasma gondii infection was 22.6%. Within the positive cases of study population, only 16 and 13 showed positive results of IL8, IL17 respectively. The results showed highly significant increase in the mean serum level of IL8 (210.25pg/ml) and IL17 (203.15 pg/ml) when compared to the control group who showed 68.9 pg/ml and 54.8 pg/ml respectively. The serum level of proinflammatory cytokines investigated in this study seems to be increased in patients with serological evidence of Toxoplasma gondii infection. Our study concludes that IL-17 and IL-8 involved in the induction of inflammation and toxoplasmosis disease.

Lactoferrin in Aseptic and Septic Inflammation

Lactoferrin (Lf), a cationic glycoprotein able to chelate two ferric irons per molecule, is synthesized by exocrine glands and neutrophils. Since the first anti-microbial function attributed to Lf, several activities have been discovered, including the relevant anti-inflammatory one, especially associated to the down-regulation of pro-inflammatory cytokines, as IL-6. As high levels of IL-6 are involved in iron homeostasis disorders, Lf is emerging as a potent regulator of iron and inflammatory homeostasis. Here, the role of Lf against aseptic and septic inflammation has been reviewed. In particular, in the context of aseptic inflammation, as anemia of inflammation, preterm delivery, Alzheimer’s disease and type 2 diabetes, Lf administration reduces local and/or systemic inflammation. Moreover, Lf oral administration, by decreasing serum IL-6, reverts iron homeostasis disorders. Regarding septic inflammation occurring in Chlamydia trachomatis infection, cystic fibrosis and inflammatory bowel disease, Lf, besides the anti-inflammatory activity, exerts a significant activity against bacterial adhesion, invasion and colonization. Lastly, a critical analysis of literature in vitro data reporting contradictory results on the Lf role in inflammatory processes, ranging from pro- to anti-inflammatory activity, highlighted that they depend on cell models, cell metabolic status, stimulatory or infecting agents as well as on Lf iron saturation degree, integrity and purity.

Optimising the collection of female genital tract fluid for cytokine analysis in pregnant women

Introduction

To better understand the immunology of pregnancy, study of female genital tract fluid (FGF) is desirable. However the optimum method of collection of FGF in pregnant women for immunological methods, specifically cytokine measurement, is unknown.

Methods

A prospective study of HIV-uninfected pregnant women comparing two methods of FGF collection: polyvinyl acetal sponge collection of cervical fluid (CF) and menstrual cup collection of cervicovaginal fluid (CVF). Samples were collected at 3 time points across the second and third trimesters: 14–21, 22–25 and 26–31 weeks. Multiplex chemi-luminescent assays were used to measure: IFN-γ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13 and TNF-α. Optimal methodology for cytokine normalisation (sample weight, volume and total protein) was explored.

Results

All cytokines were measurable in both fluid types. IL-1β, IL-8 and IL-6 were detected at the highest concentrations (ranking order CF > CVF > plasma). CVF collection was simpler, provided the largest volume of sample (median 0.5 g) with the potential for undiluted usage, and allowed for self-insertion. CF cytokine concentrations were intrinsically associated with sample weight and protein concentration however CVF cytokines were independent of these.

Conclusion

Both methods of collection are robust for measurement of FGF cytokines during pregnancy. We recommend CVF collection using a menstrual cup as a viable option in pregnant women for high dimensional biological techniques.

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PVA sponges and MCs are robust methods for measuring FGF cytokines in pregnancy.

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MCs enable collection of large undiluted CVF volumes for high dimensional assays.

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CVF (not CF) cytokine concentrations are largely independent of sample weight or protein.

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Self-insertion and short collection time of MCs is an attractive option to women.

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Cytokine concentrations are higher in sponge samples reflecting the CF immune site.

Role of Lactobacilli and Lactoferrin in the Mucosal Cervicovaginal Defense

The innate defense system of the female mucosal genital tract involves a close and complex interaction among the healthy vaginal microbiota, different cells, and various proteins that protect the host from pathogens. Vaginal lactobacilli and lactoferrin represent two essential actors in the vaginal environment. Lactobacilli represent the dominant bacterial species able to prevent facultative and obligate anaerobes outnumber in vaginal microbiota maintaining healthy microbial homeostasis. Several mechanisms underlie the protection exerted by lactobacilli: competition for nutrients and tissue adherence, reduction of the vaginal pH, modulation of immunity, and production of bioactive compounds. Among bioactive factors of cervicovaginal mucosa, lactoferrin, an iron-binding cationic glycoprotein, is a multifunctional glycoprotein with antibacterial, antifungal, antiviral, and antiparasitic activities, recently emerging as an important modulator of inflammation. Lactobacilli and lactoferrin are largely under the influence of female hormones and of paracrine production of various cytokines. Lactoferrin is strongly increased in lower genital tract mucosal fluid of women affected by Neisseria gonorrheae, Chlamydia trachomatis, and Trichomonas vaginalis infections promoting both innate and adaptive immune responses. In vaginal dysbiosis characterized by low amounts of vaginal lactobacilli and increased levels of endogenous anaerobic bacteria, the increase in lactoferrin could act as an immune modulator assuming the role normally played by the healthy microbiota in vaginal mucosa. Then lactoferrin and lactobacilli may be considered as biomarkers of altered microbial homeostasis at vaginal level. Considering the shortage of effective treatments to counteract recurrent and/or antibiotic-resistant bacterial infections, the intravaginal administration of lactobacilli and lactoferrin could be a novel efficient therapeutic strategy and a valuable tool to restore mucosal immune homeostasis.

Oral sampling methods are associated with differences in immune marker concentrations

OBJECTIVE

To determine whether the concentration and distribution of immune markers in paired oral samples were similar.

STUDY TYPE

Clinical research.

STUDY DESIGN

Cross-sectional study.

METHODS

Paired saliva and oral secretions (OS) samples were collected. The concentration of immune markers was estimated using Luminex multiplex assay (Thermo Fisher Scientific, Waltham, MA). For each sample, the concentration of respective immune markers was normalized to total protein present and log-transformed. Median concentrations of immune markers were compared between both types of samples. Intermarker correlation in each sampling method and across sampling methods was evaluated.

RESULTS

There were 90 study participants. Concentrations of immune markers in saliva samples were significantly different from concentrations in OS samples. Oral secretions samples showed higher concentrations of immunoregulatory markers, whereas the saliva samples contained proinflammatory markers in higher concentration.

CONCLUSION

The immune marker profile in saliva samples is distinct from the immune marker profile in paired OS samples.

LEVEL OF EVIDENCE

2b. Laryngoscope, 128:E214-E221, 2018.

Low Lactobacilli abundance and polymicrobial diversity in the lower reproductive tract of female rhesus monkeys do not compromise their reproductive success

The lower reproductive tract of nonhuman primates is colonized with a diverse microbiota, resembling bacterial vaginosis (BV), a gynecological condition associated with negative reproductive outcomes in women. Our 4 aims were to: (i) assess the prevalence of low Lactobacilli and a BV-like profile in female rhesus monkeys; (ii) quantify cytokines in their cervicovaginal fluid (CVF); (iii) examine the composition and structure of their mucosal microbiota with culture-independent sequencing methods; and (iv) evaluate the potential influence on reproductive success. CVF specimens were obtained from 27 female rhesus monkeys for Gram's staining, and to determine acidity (pH), and quantify proinflammatory cytokines. Based on Nugent's classification, 40% had a score of 7 or higher, which would be indicative of BV in women. Nugent scores were significantly correlated with the pH of the CVF. Interleukin-1ß was present at high concentrations, but not further elevated by high Nugent scores. Vaginal swabs were obtained from eight additional females to determine microbial diversity by rRNA gene amplicon sequencing. At the phylum level, the Firmicutes/Bacteroidetes ratio was low. The relative abundance of Lactobacilli was also low (between 3% and 17%), and 11 other genera were present at >1%. However, neither the microbial diversity in the community structure, nor high Nugent scores, was associated with reduced fecundity. Female monkeys provide an opportunity to understand how reproductive success can be sustained in the presence of a diverse polymicrobial community in the reproductive tract.

High Levels of Inflammatory Cytokines in the Reproductive Tract of Women with BV and Engaging in Intravaginal Douching: A Cross-Sectional Study of Participants in the Women Interagency HIV Study

High levels of inflammatory cytokines in the genital tract suggest mucosal vulnerability and increased risk of HIV and sexually transmitted infection (STI) acquisition. Intravaginal douching is associated with bacterial vaginosis (BV) in women in the United States, and both douching and BV are linked to HIV and STI acquisition. This study evaluates inflammatory cytokines in the genital tract to increase understanding of the effects of both BV and intravaginal douching to the vaginal mucosa. A cross-sectional study of participants in the Miami WIHS investigated 72 reproductive age women (45 HIV⁺ and 27 high-risk HIV^-) who completed intravaginal douching questionnaires and underwent collection of vaginal swabs and cervicovaginal lavages (CVLs). BV was assessed using the Nugent score. Inflammatory cytokines in the CVLs (interleukin [IL]-6, IL-8, IL-1α, IL-1β, soluble intracellular adhesion molecule-1 [sICAM-1], interferon [IFN]α2, chemokine C ligand 5 (CCL5), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP1), tumor necrosis factor alpha (TNFα), and secretory leukocyte protease inhibitor [SLPI]) were measured. Fourteen (19%) women reported intravaginal douching; 24 (33%) had BV. BV, intravaginal douching, and HIV were associated with higher levels of inflammatory cytokines. After controlling for demographic and risk factors and HIV status, women who had BV and douched had higher levels of inflammatory cytokines than those without BV and who did not douche, or who only had BV or only douched. These findings suggest that BV and douching are associated with greater mucosal inflammation and may facilitate HIV acquisition and transmission. Although longitudinal studies are needed to determine temporal associations and causality, interventions to decrease rates of intravaginal douching and BV could significantly decrease women's risks of acquiring STIs and HIV and limit the spread of HIV.

Bacterial and cytokine mixtures predict the length of gestation and are associated with miRNA expression in the cervix

AIM

Bacterial vaginosis may lead to preterm birth through epigenetic programming of the inflammatory response, specifically via miRNA expression.

METHODS

We quantified bacterial 16S rRNA, cytokine mRNA and 800 miRNA from cervical swabs obtained from 80 women at 16-19 weeks' gestation. We generated bacterial and cytokine indices using weighted quantile sum regression and examined associations with miRNA and gestational age at delivery.

RESULTS & DISCUSSION

Each decile of the bacterial and cytokine indices was associated with shorter gestations (p < 0.005). The bacterial index was associated with miR-494, 371a, 4286, 185, 320e, 888 and 23a (p < 0.05). miR-494 remained significant after false discovery rate correction (q < 0.1). The cytokine index was associated with 27 miRNAs (p < 0.05; q < 0.01).

CONCLUSION

Future investigation into the role of bacterial vaginosis- and inflammation-associated miRNA and preterm birth is warranted.

Cervicovaginal cytokines, sialidase activity and bacterial load in reproductive-aged women with intermediate vaginal flora

Studies have shown that not only bacterial vaginosis, but also intermediate vaginal flora has deleterious effects for women's reproductive health. However, literature still lacks information about microbiological and immunological aspects of intermediate flora.

OBJECTIVE

To characterize intermediate flora regarding levels of Interleukin (IL)-1beta, IL-6, IL-8, tumor necrosis factor-alpha, interleukin 1 receptor antagonist (IL-1ra), IL-10, sialidase; loads of Gardnerella vaginalis, total bacteria and to verify whether it is closer related to normal flora or bacterial vaginosis. This cross-sectional study enrolled 526 non-pregnant reproductive-aged women distributed in 3 groups according to pattern of vaginal flora using Nugent's system in normal, intermediate and bacterial vaginosis. Cervicovaginal levels of cytokines, sialidases, loads of G. vaginalis and total bacteria were assessed by ELISA, conversion of MUAN and quantitative real-time PCR, respectively. A principal component analysis(PCA) using all measured parameters was performed to compare the three different types of flora. Results showed that intermediate flora is associated with increased cervicovaginal IL-1beta in relation to normal flora(P<0.0001). When compared to bacterial vaginosis, intermediate flora has higher IL-8 and IL-10 levels(P<0.01). Sialidases were in significantly lower levels in normal and intermediate flora than bacterial vaginosis(P<0.0001). Loads of G. vaginalis and total bacterial differed among all groups(P<0.0001), being highest in bacterial vaginosis. PCA showed that normal and intermediate flora were closely scattered, while bacterial vaginosis were grouped separately.

CONCLUSION

Although intermediate flora shows some differences in cytokines, sialidases and bacterial loads in relation to normal flora and bacterial vaginosis, when taken together, general microbiological and immunological pattern pattern of intermediate flora resembles the normal flora.

Regulatory Cytokine Expression and Preterm Birth: Case-Control Study Nested in a Cohort

Background

Currently known risk factors explain only a small fraction of preterm birth (PTB). Previous PTB is one of the most important predictors. However, this information is not available in primiparous women. Few studies have looked at associations between regulatory cytokine expression (RCE) and PTB and the results are conflicting.

Objective

To investigate the association of RCE–Interleukin 10 (IL-10) and Transforming Growth Factor β (TGF-β)–with PTB, and to assess whether bacterial vaginosis (BV) is involved in this relationship.

Methods

This was a case-control study nested in a prospective cohort–called BRISA. Women with singleton pregnancies were interviewed from 22 to 25 weeks of gestational age (GA). Women were recruited from health services in São Luís, Brazil. A blood sample was collected and gynecological examination was performed. Serum IL-10 and TGF-β were determined using cytometric bead array. Nugent score >7 and/or the presence of clue cells were used for BV diagnosis. All PTB estimated by ultrasound dating performed before 20 weeks of gestational age were considered cases. Controls were selected by simple random sampling from the rest of the cohort, at a 2:1 ratio. Different models were tested, according to the main independent variable. Odds ratios (OR) and 95% confidence intervals (95%CI) were estimated by regression analyses.

Results

The study included 327 pregnant women, 109 cases and 218 controls. No associations were found between BV and PTB (P = 1.44; 95%CI: 0.51–3.77). Low levels of IL-10 (OR = 2.92 95%CI: 1.38–6.16) or TGF-β (OR = 16.90 95%CI: 6.42–44.51) or both simultaneously (OR = 77.16 95%CI: 7.99–744.88) were associated with increasing odds of PTB, even after adjustment for confounding.

Conclusion

Decreased RCE is a risk factor for PTB. This relationship, however, is not triggered by the presence of BV. Low IL-10/TGF-β levels from 22 to 25 weeks of GA could be used as early predictors of PTB. We suggest monitoring of these RCE, especially among primiparous women, for whom history of previous PTB is not available.

Bacterial vaginosis in pregnant adolescents: proinflammatory cytokine and bacterial sialidase profile. Cross-sectional study

CONTEXT AND OBJECTIVE

Bacterial vaginosis occurs frequently in pregnancy and increases susceptibility to sexually transmitted infections (STI). Considering that adolescents are disproportionally affected by STI, the aim of this study was to evaluate the cervicovaginal levels of interleukin (IL)-1 beta, IL-6, IL-8 and bacterial sialidase in pregnant adolescents with bacterial vaginosis.

DESIGN AND SETTING

Cross-sectional study at mother and child referral units in Belém, Pará, Brazil.

METHODS

Vaginal samples from 168 pregnant adolescents enrolled were tested for trichomoniasis and candidiasis. Their vaginal microbiota was classified according to the Nugent criteria (1991) as normal, intermediate or bacterial vaginosis. Cervical infection due to Chlamydia trachomatisand Neisseria gonorrhoeae was also assessed. Cytokine and sialidase levels were measured, respectively, using enzyme-linked immunosorbent assays and MUAN conversion in cervicovaginal lavages. Forty-eight adolescents (28.6%) were excluded because they tested positive for some of the infections investigated. The remaining 120 adolescents were grouped according to vaginal flora type: normal (n = 68) or bacterial vaginosis (n = 52). Their cytokine and sialidase levels were compared between the groups using the Mann-Whitney test (P < 0.05).

RESULTS

The pregnant adolescents with bacterial vaginosis had higher levels of IL-1 beta, IL-6 and IL-8 (P < 0.05). Sialidase was solely detected in 35 adolescents (67.2%) with bacterial vaginosis.

CONCLUSIONS

Not only IL-1 beta and sialidase levels, but also IL-6 and IL-8 levels are higher in pregnant adolescents with bacterial vaginosis, thus indicating that this condition elicits a more pronounced inflammatory response in this population, which potentially increases vulnerability to STI acquisition.

Antimicrobial and immune modulatory effects of lactic acid and short chain fatty acids produced by vaginal microbiota associated with eubiosis and bacterial vaginosis

Lactic acid and short chain fatty acids (SCFAs) produced by vaginal microbiota have reported antimicrobial and immune modulatory activities indicating their potential as biomarkers of disease and/or disease susceptibility. In asymptomatic women of reproductive-age the vaginal microbiota is comprised of lactic acid-producing bacteria that are primarily responsible for the production of lactic acid present at ~110 mM and acidifying the vaginal milieu to pH ~3.5. In contrast, bacterial vaginosis (BV), a dysbiosis of the vaginal microbiota, is characterized by decreased lactic acid-producing microbiota and increased diverse anaerobic bacteria accompanied by an elevated pH>4.5. BV is also characterized by a dramatic loss of lactic acid and greater concentrations of mixed SCFAs including acetate, propionate, butyrate, and succinate. Notably women with lactic acid-producing microbiota have more favorable reproductive and sexual health outcomes compared to women with BV. Regarding the latter, BV is associated with increased susceptibility to sexually transmitted infections (STIs) including HIV. In vitro studies demonstrate that lactic acid produced by vaginal microbiota has microbicidal and virucidal activities that may protect against STIs and endogenous opportunistic bacteria as well as immune modulatory properties that require further characterization with regard to their effects on the vaginal mucosa. In contrast, BV-associated SCFAs have far less antimicrobial activity with the potential to contribute to a pro-inflammatory vaginal environment. Here we review the composition of lactic acid and SCFAs in respective states of eubiosis (non-BV) or dysbiosis (BV), their effects on susceptibility to bacterial/viral STIs and whether they have inherent microbicidal/virucidal and immune modulatory properties. We also explore their potential as biomarkers for the presence and/or increased susceptibility to STIs.

Bacterial vaginosis and the cervicovaginal immune response

Bacterial vaginosis (BV) is a common cause of vaginal discharge in reproductive age women around the world and is associated with several poor reproductive health outcomes, including HIV-1 acquisition. One possible mechanism for this association is the inflammatory immune response induced by BV in the cervical and vaginal mucosae. There is significant heterogeneity in reports of markers of cervicovaginal inflammation in women with BV, likely due to microbial and host diversity, as well as differences in study design. In this article, we review the characteristics of the mucosal immune response in BV, the potential role of lactobacilli in modulating that response, and the impact of individual BV-associated bacterial species on mucosal immunity. We focus on inflammatory markers that are proposed to increase the risk of HIV-1 acquisition.

Microbiome in human immunodeficiency virus infection

Human immunodeficiency virus (HIV) primary infection occurs at mucosa tissues, suggesting an intricate interplay between the microbiome and HIV infection. Recent advanced technologies of high-throughput sequencing and bioinformatics allow researchers to explore nonculturable microbes, including bacteria, virus, and fungi, and their association with diseases. HIV/simian immunodeficiency virus infection is associated with microbiome shifts and immune activation that may affect the outcome of disease progression. In this review, the authors focus on microbiome in HIV infection at various mucosal compartments. Understanding the relationship between microbiome and HIV may offer insights into development of better strategies for HIV prevention and treatment.

The changing landscape of the vaginal microbiome

Deep sequence analysis of the vaginal microbiome is revealing an unexpected complexity that was not anticipated as recently as several years ago. The lack of clarity in the definition of a healthy vaginal microbiome, much less an unhealthy vaginal microbiome, underscores the need for more investigation of these phenomena. Some clarity may be gained by the careful analysis of the genomes of the specific bacteria in these women. Ongoing studies will clarify this process and offer relief for women with recurring vaginal maladies and hope for pregnant women to avoid the experience of preterm birth.

Pregnancy-induced changes in immune protection of the genital tract: defining normal

OBJECTIVE

Both the state of pregnancy as well as disruption of vaginal flora and immune mediators may increase the risk of human immunodeficiency virus-1 acquisition. The objective of this study was to define immune changes in lower genital and systemic immunity associated with normal pregnancy.

STUDY DESIGN

This prospective cohort enrolled low-risk pregnant and nonpregnant women ages 18-35 years. Pregnant women at <14 weeks and nonpregnant women in follicular phase of the menstrual cycle were included. Cervical and vaginal fluid was collected. Concentrations of immune mediators were measured using enzyme-linked immunosorbent assay-based methods or multiplex immunoassay. Samples were inoculated onto various culture media allowing for growth of Lactobacillus species, Gardnerella vaginalis, Escherichia coli, Enterococcus species, anaerobic gram-negative rods, Candida, Staphylococcus aureus, Ureaplasma species, and Mycoplasma hominis. Concentrations of immune mediators and vaginal colonization frequencies were compared between the pregnant and nonpregnant groups.

RESULTS

Genital tract concentration of interleukin-1β was higher during pregnancy compared to nonpregnant participants. Serum C-reactive protein concentrations were higher in all trimesters of pregnancy. Concentrations of secretory leukocyte protease inhibitor did not differ between groups. Lactobacillus was more commonly isolated from vaginal cultures of nonpregnant participants (100% vs 70.2%, P = .02). Identification of Candida, G vaginalis, M hominis, and S aureus was common and not different between groups. Ureaplasma species was isolated from >60% pregnant participants.

CONCLUSION

The proinflammatory cytokine, interleukin-1β, as well as the systemic marker of inflammation, C-reactive protein, are increased during pregnancy. The impact of these proinflammatory changes during pregnancy deserves further study.

Dietary supplementation with probiotics during late pregnancy: outcome on vaginal microbiota and cytokine secretion

Background

The vaginal microbiota of healthy women consists of a wide variety of anaerobic and aerobic bacterial genera and species dominated by the genus Lactobacillus. The activity of lactobacilli helps to maintain the natural healthy balance of the vaginal microbiota. This role is particularly important during pregnancy because vaginal dismicrobism is one of the most important mechanisms for preterm birth and perinatal complications. In the present study, we characterized the impact of a dietary supplementation with the probiotic VSL#3, a mixture of Lactobacillus, Bifidobacterium and Streptococcus strains, on the vaginal microbiota and immunological profiles of healthy women during late pregnancy.

Results

An association between the oral intake of the probiotic VSL#3 and changes in the composition of the vaginal microbiota of pregnant women was revealed by PCR-DGGE population profiling. Despite no significant changes were found in the amounts of the principal vaginal bacterial populations in women administered with VSL#3, qPCR results suggested a potential role of the probiotic product in counteracting the decrease of Bifidobacterium and the increase of Atopobium, that occurred in control women during late pregnancy. The modulation of the vaginal microbiota was associated with significant changes in some vaginal cytokines. In particular, the decrease of the anti-inflammatory cytokines IL-4 and IL-10 was observed only in control women but not in women supplemented with VSL#3. In addition, the probiotic consumption induced the decrease of the pro-inflammatory chemokine Eotaxin, suggesting a potential anti-inflammatory effect on the vaginal immunity.

Conclusion

Dietary supplementation with the probiotic VSL#3 during the last trimester of pregnancy was associated to a modulation of the vaginal microbiota and cytokine secretion, with potential implications in preventing preterm birth.

Trial registration

ClinicalTrials.gov NCT01367470

Host remodeling of the gut microbiome and metabolic changes during pregnancy

Many of the immune and metabolic changes occurring during normal pregnancy also describe metabolic syndrome. Gut microbiota can cause symptoms of metabolic syndrome in nonpregnant hosts. Here, to explore their role in pregnancy, we characterized fecal bacteria of 91 pregnant women of varying prepregnancy BMIs and gestational diabetes status and their infants. Similarities between infant-mother microbiotas increased with children's age, and the infant microbiota was unaffected by mother's health status. Gut microbiota changed dramatically from first (T1) to third (T3) trimesters, with vast expansion of diversity between mothers, an overall increase in Proteobacteria and Actinobacteria, and reduced richness. T3 stool showed strongest signs of inflammation and energy loss; however, microbiome gene repertoires were constant between trimesters. When transferred to germ-free mice, T3 microbiota induced greater adiposity and insulin insensitivity compared to T1. Our findings indicate that host-microbial interactions that impact host metabolism can occur and may be beneficial in pregnancy.

In vitro anti-HIV-1 activity in cervicovaginal secretions from pregnant and nonpregnant women

OBJECTIVE

To evaluate whether cervicovaginal secretions inhibit HIV-1 infectivity in an in vitro model, and estimate concentration of immune mediators.

STUDY DESIGN

We enrolled midtrimester pregnant and regularly menstruating (nonpregnant) women. Cervicovaginal lavage was collected at 2 visits and incubated with HIV-1 and TZM-bl cells. Infectivity was compared with positive controls. Concentrations of immune mediators were compared between groups.

RESULTS

At enrollment, cervicovaginal lavage inhibited IIIB virus 88.2% and 82.4%, and BaL virus 72.8% and 77.9%, among pregnant (n = 13) and nonpregnant women (n = 9), respectively. At second visit, cervicovaginal lavage inhibited IIIB 89.7% and 82.5%, and BaL 77.4% and 69.9% among pregnant (n = 15) and nonpregnant women (n = 8), respectively (all P ≤ .04). Adjusting for body mass index, race, and protein content of cervicovaginal lavage, antimicrobials were suppressed but cytokines and chemokines were not markedly different in pregnancy.

CONCLUSION

Cervicovaginal secretions significantly suppress HIV-1 infectivity in this model. Concentrations of certain immune mediators are altered in pregnancy.

Immunomodulatory factors in cervicovaginal secretions from pregnant and non-pregnant women: a cross-sectional study

BACKGROUND

Pregnant women are at an increased risk for HIV infection due to unknown biological causes. Given the strong effect of sex-hormones on the expression of immunomuodulatory factors, the central role of mucosal immunity in HIV pathogenesis and the lack of previous studies, we here tested for differences in immunomuodulatory factors in cervico-vaginal secretions between pregnant and non-pregnant women.

METHODS

We compared concentrations of 39 immunomodulatory factors in cervicovaginal lavages (CVL) from 21 pregnant women to those of 24 non-pregnant healthy women from the US. We used Bonferroni correction to correct for multiple testing and linear regression modeling to adjust for possible confounding by plasma cytokine concentration, cervical ectopy, total protein concentration, and other possible confounders. Cervical ectopy was determined by planimetry. Concentration of immunomodulatory factors were measured by a multiplex assay, protein concentration by the Bradford Method.

RESULTS

Twenty six (66%) of the 39 measured immunomodulatory factors were detectable in at least half of the CVL samples included in the study. Pregnant women had threefold lower CVL concentration of CCL22 (geometric mean: 29.6 pg/ml versus 89.7 pg/ml, p = 0.0011) than non-pregnant women. CVL CCL22 concentration additionally correlated negatively with gestational age (Spearman correlation coefficient [RS]: -0.49, p = 0.0006). These associations remained significant when corrected for multiple testing. CCL22 concentration in CVL was positively correlated with age and negatively correlated with time since last coitus and the size of cervical ectopy. However, none of these associations could explain the difference of CCL22 concentration between pregnant and non-pregnant women in this study, which remained significant in adjusted analysis.

CONCLUSIONS

In this study population, pregnancy is associated with reduced concentrations of CCL22 in cervicovaginal secretions. The role of CCL22 on HIV transmission should now be investigated in prospective studies.

Effects of pregnancy and bacterial vaginosis on proinflammatory cytokine and secretory leukocyte protease inhibitor concentrations in vaginal secretions

We compared vaginal proinflammatory cytokine and secretory leukocyte protease inhibitor (SLPI) concentrations among pregnant and nonpregnant women according to bacterial vaginosis (BV) status. One-hundred and twenty-two women at 12–20 weeks' gestation and 133 nonpregnant controls had vaginal concentrations of interleukin (IL)-1β, IL-6, IL-8, and SLPI measured by enzyme immunoassay. Multivariable linear regression was used to evaluate factors independently associated with vaginal cytokine and SLPI response. Pregnancy and BV were both independently associated with increased vaginal concentrations of IL-1β and IL-8; pregnant women had increased concentrations of SLPI, while women with BV had decreased SLPI concentrations.

Changes in the vaginal microenvironment with metronidazole treatment for bacterial vaginosis in early pregnancy

OBJECTIVE

Bacterial vaginosis (BV) is associated with preterm delivery, but there is little evidence that treatment improves pregnancy outcomes. We examined whether oral or vaginal metronidazole treatment for BV in early pregnancy was more effective in restoring the normal vaginal environment.

METHODS

This was a randomized controlled trial comparing oral and intravaginal metronidazole for treatment of BV in early pregnancy (<20 weeks). Vaginal samples collected at baseline and 4 weeks after treatment were evaluated using gram stain, culture, colorimetric detection of sialidase, and immunoassay for measurement of proinflammatory cytokines interleukins-1beta, -6, -8 (IL-1beta, IL-6, IL-8) and secretory leukocyte protease inhibitor (SLPI). We compared the effect of treatment between groups (using chi-square and t test) and within individuals (McNemar's test).

RESULTS

Of 126 subjects, 108 (86%) completed follow-up (55 oral, 53 intravaginal). Of the study population, 34% achieved therapeutic cure, and this was not different between treatment groups. BV-associated bacteria were significantly reduced in both groups, but few subjects regained colonization with protective lactobacilli. Among women who achieved therapeutic cure, the level of IL-1beta dropped significantly (p < 0.001) and SLPI increased (p = 0.003). More women in the vaginal treatment group had undetectable sialidase after treatment (p = 0.013).

CONCLUSIONS

Treatment with oral or intravaginal metronidazole in early pregnancy reduced colonization with BV-associated bacteria but was not effective in achieving therapeutic cure or in restoring healthy vaginal lactobacilli.

Vaginal and oral microbes, host genotype and preterm birth

Preterm birth (PTB) is a leading cause of infant mortality and morbidity in the US and across the globe. Infection and associated inflammation are important initiators for PTB pathways; an estimated 40% of PTBs are attributed to amniochorionic-decidual or systemic inflammation. Historically, intrauterine infections have been implicated in PTB; recent evidence suggests that infections remote from the fetal site may also be causative. There is strong epidemiological evidence that bacterial vaginosis and periodontitis--two syndromes characterized by perturbations in the normal vaginal and oral bacterial microflora, respectively--are linked to infection-associated PTB. Oral and vaginal environments are similar in their bacterial microbiology; identical bacterial species have been independently isolated in periodontitis and bacterial vaginosis. Periodontitis and bacterial vaginosis also share many behavioral and sociodemographic risk factors suggesting a possible common pathophysiology. Genetic polymorphisms in host inflammatory responses to infection are shared between bacterial vaginosis, periodontitis and PTB, suggesting common mechanisms through which host genotype modify the effect of abnormal bacterial colonization on preterm birth. We review the state of knowledge regarding the risk of PTB attributable to perturbations in bacterial flora in oral and vaginal sites and the role of host genetics in modifying the risk of infection-related PTB. We posit that bacterial species that are common in perturbed vaginal and oral sites are associated with PTB through their interaction with the host immune system.

Human immunodeficiency virus serodiscordant couples on highly active antiretroviral therapies with undetectable viral load: conception by unprotected sexual intercourse or by assisted reproduction techniques?

Until recently, only assisted reproduction was proposed to serodiscordant couples wishing to conceive. Nevertheless, recent publications have proposed unprotected sexual intercourse, targeting fertile days, for couples where antiretroviral treatment has lowered blood viral load to an undetectable level. Available data and the arguments for and against conception by safe sex versus the use of a strategy of unprotected sexual intercourse targeting fertile days are reviewed and analyzed. Although the rate of transmission of human immunodeficiency virus in serodiscordant couples in precise conditions (such as an undetectable viral load on treatment by highly active antiretroviral therapies and sexual intercourse limited to the fertile days) is very low, not zero, here we stress the various factors which can increase the risk of seroconversion in this particular population. In this context, it seems less cautious to abandon the recommendations of safe sex in serodiscordant couples desiring a child. The recourse to medically assisted procreation is advised, as long as evidence from further studies does not show that unprotected sexual intercourse, targeted to fertile days, does not have unexpected harmful consequences.

Detection of fastidious vaginal bacteria in women with HIV infection and bacterial vaginosis

BACKGROUND

Fastidious bacteria have been associated with bacterial vaginosis (BV) using PCR methods. We assessed the prevalence of these bacteria in HIV-1 infected women and their relationship with vaginal pH and shedding of HIV-1 RNA.

METHODS

64 cervicovaginal lavage (CVL) samples were collected from 51 women. Vaginal microbiota were characterized using 8 bacterium-specific quantitative PCR assays.

RESULTS

Women with the fastidious bacteria Bacterial Vaginosis Associated Bacterium (BVAB) 1, 2, and 3 showed a trend to increased HIV-1 shedding (OR 2.59-3.07, P = .14-.17). Absence of Lactobacillus crispatus (P < .005) and presence of BVAB2 (P < .001) were associated with elevated vaginal pH. BVAB1, 2, and 3 were highly specific indicators of BV in HIV-infected women, with specificities of 89%-93%.

CONCLUSIONS

Fastidious bacteria (BVAB 1, 2, and 3) remain specific indicators of BV in HIV-infected women, and BVAB2 may contribute to the elevated vaginal pH that is a hallmark of this syndrome.

[Bacterial vaginosis]

Bacterial vaginosis is a widely spread health problem with multiple connotations. It has been the subject of many studies and work during decades and it still remains a polemic entity, with contradictory finding. The polymicrobian etiology, unsolved epidemiology, obstetrico-gynecological complications and high recurrence rate following treatment, make this infection a target for researchers. It is not an inflammatory process -yet an immune response exists. In this disorder, vaginal discharge increases, and it is associated with a high risk of developing sexually transmitted diseases.

Cytokine networks and the regulation of uterine function in pregnancy and parturition

Complex cytokine networks play an important role in a wide range of reproductive and pregnancy related processes. Here, we review the current knowledge concerning the impact of cytokines on uterine physiology and pathophysiology. Cytokines influence a range of uterine functions during the menstrual cycle, implantation, pregnancy and labour. The synergistic interactions between individual cytokines are intricate and dynamic, and modulated by pregnancy hormones. It is not surprising therefore, that perturbations to cytokine signalling are associated with adverse pregnancy outcomes, such as miscarriage, pre-eclampsia, preterm labour and foetal brain injury. Further insight into the complexity of cytokine networks will be required to develop novel therapeutic strategies for the treatment of cytokine imbalances in pregnancy.