Bacterial vaginosis and HIV seroprevalence among female commercial sex workers in Chiang Mai, Thailand

The microbial revolution: Unveiling the benefits of vaginal probiotics and prebiotics

Vaginal health is essential to a woman's overall well-being, as abnormalities in vaginal health can lead to a variety of gynaecological disorders, such as urinary tract infections, yeast infections, and bacterial vaginosis. The vaginal microbiome is essential for the prevention of these infections. Disruptions in this microbial ecosystem can significantly impact vaginal health. The concept of utilizing probiotics and prebiotics to stimulate the growth of protective vaginal microbiota has gathered substantial interest in recent years. Probiotics are live micro-organisms that strengthen and restore vaginal microbial balance by lowering pH levels, production of bacteriocins, biofilm disruption, modulation of immune response, and production of hydrogen peroxide (H2O2), consequently combating the development of pathogens. Prebiotics are oligosaccharides that encourage the development of probiotics such as lactobacilli species. Probiotics and prebiotics also have some broader implications for vaginal health, including their role in minimizing the incidence of premature birth, optimizing fertility, managing menopausal symptoms, and preventing vaginal infections. Synbiotics are a combination of probiotics and prebiotics that deliver additional benefits by encouraging the development and activity of beneficial microbes. Furthermore, postbiotics are bioactive compounds derived from probiotic bacteria during fermentation that have immunomodulatory actions and provide an additional layer of protection against vaginal infections. The present study highlights the most prevalent vaginal infections and limitations of existing therapies that influence the vaginal microbiota. The profound consequences of probiotics and prebiotics in women's health, including their role in minimizing the prevalence of vaginal infections and promoting overall vaginal health, as well as advanced therapeutic strategies such as synbiotics and postbiotics, are also discussed. The literature offers significant insights into the mechanism, efficacy, and safety of probiotics and prebiotics to healthcare providers and researchers.

2-Hydroxyisovalerate Is Produced During Bacterial Vaginosis and Boosts HIV Infection in Resting T Cells

Human immunodeficiency virus (HIV) infection and the ensuing acquired immunodeficiency syndrome (AIDS) disproportionally affect young women, yet understanding of the factors promoting heterosexual transmission in the female genital tract is limited. Colonization with highly diverse, Lactobacillus-deficient communities (HDCs) increases a woman's risk of acquiring HIV-1 compared with colonization with Lactobacillus-dominated low diversity communities (LDCs). The polymicrobial nature of these communities has made it challenging to elucidate the microbial mechanisms responsible for modulating HIV susceptibility. Here, we analyzed conserved changes in small-molecule metabolites present in the cervicovaginal lavage fluid collected from women colonized with HDCs and LDCs with the goal of identifying possible chemicals influencing HIV infection. As in previous studies, we found that the catabolite of the branched-chain amino acid valine, 2-hydroxyisovalerate (2-HV), was a consistent component of dysbiotic HDC microbiota. Effects of 2-HV on HIV infection were assessed. In experimental infections with HIV, treatment with 2-HV increased infections of resting CD4+ T cells. To understand bacterial production of 2-HV in more detail, we cultured purified HDC and LDC bacteria and used mass spectrometry to identify two HDC bacteria that synthesize high levels of 2-HV. In contrast, protective vaginal Lactobacilli did not produce high levels of 2-HV. A genomic analysis of genes encoding 2-HV synthetic pathways showed a correlation between high-level production of 2-HV and pathways for synthesis of the immediate precursor 2-ketoisovalerate. Thus, 2-HV is a candidate mediator linking vaginal microbiome structure and heterosexual HIV transmission in women.

Sub-communities of the vaginal microbiota in pregnant and non-pregnant women

Diverse and non-Lactobacillus-dominated vaginal microbial communities are associated with adverse health outcomes such as preterm birth and the acquisition of sexually transmitted infections. Despite the importance of recognizing and understanding the key risk-associated features of these communities, their heterogeneous structure and properties remain ill-defined. Clustering approaches are commonly used to characterize vaginal communities, but they lack sensitivity and robustness in resolving substructures and revealing transitions between potential sub-communities. Here, we address this need with an approach based on mixed membership topic models. Using longitudinal data from cohorts of pregnant and non-pregnant study participants, we show that topic models more accurately describe sample composition, longitudinal changes, and better predict the loss of Lactobacillus dominance. We identify several non-Lactobacillus-dominated sub-communities common to both cohorts and independent of reproductive status. In non-pregnant individuals, we find that the menstrual cycle modulates transitions between and within sub-communities, as well as the concentrations of half of the cytokines and 18% of metabolites. Overall, our analyses based on mixed membership models reveal substructures of vaginal ecosystems which may have important clinical and biological associations.

Optimizing the vaginal microbiome as a potential strategy to reduce heterosexual HIV transmission

Bacterial vaginosis (BV) is a proinflammatory genital condition characterized by high vaginal bacterial diversity and a paucity of Lactobacillus species. BV has been linked to an elevated risk of HIV acquisition among HIV-negative women and of forward HIV transmission to male sex partners among women living with HIV (adjusted hazard ratios of 1.69 and 3.17, respectively), potentially by eliciting genital inflammation in women with BV and their male sex partners. BV is also highly prevalent among women in sub-Saharan Africa, suggesting that BV treatment may have potential as an HIV prevention strategy. BV is typically treated with antibiotics but recurrence rates are high, possibly because treatment does not directly promote Lactobacillus growth. More recently, BV treatment strategies incorporating live biotherapeutic lactobacilli have led to sustained optimization of the vaginal microbiome and a decrease in inflammatory biomarkers previously associated with HIV susceptibility. Future studies are urgently needed to evaluate BV treatment strategies that can optimize the vaginal microbiome in the long term through colonization with H₂ O₂ -producing vaginal lactobacilli and to assess whether vaginal microbiota optimization is able to reduce the risk of HIV transmission.

Altered Innate Immunity and Damaged Epithelial Integrity in Vaginal Microbial Dysbiosis

The role of neutrophils relative to vaginal dysbiosis is unclear. We hypothesize that bacterial vaginosis (BV)-associated bacteria may induce the activation and accumulation of mucosal neutrophils within the female reproductive tract (FRT), resulting in epithelial barrier damage. We collected endocervical cytobrushes from women with and without BV and assessed bacteria community type and frequency/functional phenotypes of neutrophils. We performed in vitro whole blood co-cultures with BV-associated bacteria and healthy vaginal commensals and assessed their impact on epithelial integrity using transepithelial electrical resistance. We demonstrated increased neutrophil frequency (p < 0.0001), activation (p < 0.0001), and prolonged lifespan (p < 0.0001) in the cytobrushes from women with non-Lactobacillus dominant (nLD) communities. Our in vitro co-cultures confirmed these results and identified significant barrier damage in the presence of neutrophils and G. vaginalis. Here, we demonstrate that BV-associated bacteria induce neutrophil activation and increase lifespan, potentially causing accumulation in the FRT and epithelial barrier damage.

The Vaginal Microbiome: III. The Vaginal Microbiome in Various Urogenital Disorders

OBJECTIVE

This series of articles, titled The Vaginal Microbiome (VMB), written on behalf of the International Society for the Study of Vulvovaginal Disease, aims to summarize the recent findings and understanding of the vaginal bacterial microbiota, mainly regarding areas relevant to clinicians specializing in vulvovaginal disorders.

MATERIALS AND METHODS

A search of PubMed database was performed, using the search terms "vaginal microbiome" with "Candida," "vaginitis," "urinary microbiome," "recurrent urinary tract infections," "sexually transmitted infections," "human immunodeficiency virus," "human papillomavirus," "nonspecific vaginitis," "vulvodynia," and "vulvovaginal symptoms." Full article texts were reviewed. Reference lists were screened for additional articles. The third article in this series describes VMB in various urogenital disorders.

RESULTS

Variable patterns of the VMB are found in patients with vulvovaginal candidiasis, challenging the idea of a protective role of lactobacilli. Highly similar strains of health-associated commensal bacteria are shared in both the bladder and vagina of the same individual and may provide protection against urinary tract infections. Dysbiotic VMB increases the risk of urinary tract infection. Loss of vaginal lactic acid-producing bacteria combined with elevated pH, increase the risk for sexually transmitted infections, although the exact protective mechanisms of the VMB against sexually transmitted infections are still unknown.

CONCLUSIONS

The VMB may constitute a biological barrier to pathogenic microorganisms. When the predominance of lactobacilli community is disrupted, there is an increased risk for the acquisition of various vaginal pathogents. Longitudinal studies are needed to describe the association between the host, bacterial, and fungal components of the VMB.

Strong correlation between urine and vaginal swab samples for bacterial vaginosis

Background

Vaginal swabs have been traditionally used for the diagnosis of bacterial vaginosis (BV). Currently, there are limited studies that have investigated the use of other sample types other than vaginal swabs for the detection of BV from South African populations. This study investigated whether urine can be used for the detection of BV-associated microorganisms in South African pregnant women.

Methods

One-hundred self-collected vaginal swabs and urine samples were obtained from women presenting for antenatal care at King Edward VIII Hospital in Durban. The BD MAX™ vaginal panel assay was used for diagnosing BV and droplet digital polymerase chain reaction was used to quantify Gardnerella vaginalis, Prevotella bivia, Atopobium vaginae and Lactobacillus crispatus. The absolute counts were determined on the QX200 Droplet Reader (Bio-Rad) using the QuantaSoft Software. Data analysis was performed with statistical computing software called R, version 3.6.1.

Results

Median copy numbers obtained for G. vaginalis and P. bivia across urine and swabs in BV-positive samples were not significantly different (p = 0.134 and p = 0.652, respectively). This was confirmed by the correlation analysis that showed a good correlation between the two sample types (G. vaginalis [r = 0.63] and P. bivia [r = 0.50]). However, the data obtained for A. vaginae differed, and a weak correlation between urine and swabs was observed (r = 0.21). Bacterial vaginosis-negative samples had no significant difference in median copy numbers for L. crispatus across the urine and swabs (p = 0.062), and a good correlation between the sample types was noted (r = 0.71).

Conclusion

This study highlights the appropriateness of urine for the detection of microorganisms associated with BV.

Treatment of Male Sexual Partners of Women With Bacterial Vaginosis: A Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

We aimed to determine if treatment of male sexual partners of women with recurrent bacterial vaginosis (BV) with oral metronidazole 2×/day for 7 days (ie, multidose metronidazole) significantly decreased BV recurrence rates in the female.

METHODS

This was a multicenter, 2-arm, double-blind, placebo-controlled study. Women with recurrent BV and current diagnosis of BV by Amsel and Nugent were enrolled. Multidose metronidazole for 7 days was dispensed to women. Male partners were randomized to placebo versus multidose metronidazole for 7 days and asked to refrain from unprotected sex for 14 days. Female follow-up visits were conducted at day 21 and 8 and 16 weeks. Male follow-up visits occurred at days 14-21. BV cure was defined as 0-2 Amsel criteria and Nugent score 0-6 in the female partner with the primary endpoint at 16 weeks.

RESULTS

214 couples were enrolled. In the intent-to-treat population, there was no significant difference between treatment arms for the primary outcome. BV treatment failure occurred in 81% and 80% of women in the metronidazole and placebo arms through the third follow-up visit, respectively (P > .999). However, women whose male partners adhered to study medication were less likely to fail treatment (adjusted relative risk, .85; 95% CI, .73-.99; P = .035). This finding persisted in post hoc comparisons in the metronidazole arm.

CONCLUSIONS

Overall, this study did not find that male partner treatment with multidose metronidazole significantly reduces BV recurrence in female partners, although women whose partners adhered to multidose metronidazole were less likely to fail treatment.

CLINICAL TRIALS REGISTRATION

(NCT02209519).

Vaginal dysbiosis associated-bacteria Megasphaera elsdenii and Prevotella timonensis induce immune activation via dendritic cells

Dysbiosis of the vaginal microbiome as a result of overgrowth of anaerobic bacteria leads to bacterial vaginosis (BV) which is associated with increased inflammation in the genital mucosa. Moreover, BV increases susceptibility to sexual transmitted infections (STIs) and is associated with adverse pregnancy outcomes. It remains unclear how specific vaginal aerobic and anaerobic bacteria affect health and disease. We selected different vaginal bacteria ranging from true commensals to species associated with dysbiosis and investigated their effects on activation of dendritic cells (DCs). Commensal Lactobacilli crispatus did not induce DC maturation nor led to production of pro-inflammatory cytokines. In contrast, BV-associated bacteria Megasphaera elsdenii and Prevotella timonensis induced DC maturation and increased levels of pro-inflammatory cytokines. Notably, DCs stimulated with Prevotella timonensis suppressed Th2 responses and induced Th1 skewing, typically associated with preterm birth. In contrast, Lactobacillus crispatus and Megasphaera elsdenii did not affect Th cell polarization. These results strongly indicate that the interaction of vaginal bacteria with mucosal DCs determines mucosal inflammation and we have identified the anaerobic bacterium Prevotella timonensis as a strong inducer of inflammatory responses. Specifically targeting these inflammation-inducing bacteria might be a therapeutic strategy to prevent BV and associated risks in STI susceptibility and preterm birth.

The genital tract and rectal microbiomes: their role in HIV susceptibility and prevention in women

INTRODUCTION

Young women in sub-Saharan Africa are disproportionately affected by HIV, accounting for 25% of all new infections in 2017. Several behavioural and biological factors are known to impact a young woman's vulnerability for acquiring HIV. One key, but lesser understood, biological factor impacting vulnerability is the vaginal microbiome. This review describes the vaginal microbiome and examines its alterations, its influence on HIV acquisition as well as the efficacy of HIV prevention technologies, the role of the rectal microbiome in HIV acquisition, advances in technologies to study the microbiome and some future research directions.

DISCUSSION

Although the composition of each woman's vaginal microbiome is unique, a microbiome dominated by Lactobacillus species is generally associated with a "healthy" vagina. Disturbances in the vaginal microbiota, characterized by a shift from a low-diversity, Lactobacillus-dominant state to a high-diversity non-Lactobacillus-dominant state, have been shown to be associated with a range of adverse reproductive health outcomes, including increasing the risk of genital inflammation and HIV acquisition. Gardnerella vaginalis and Prevotella bivia have been shown to contribute to both HIV risk and genital inflammation. In addition to impacting HIV risk, the composition of the vaginal microbiome affects the vaginal concentrations of some antiretroviral drugs, particularly those administered intravaginally, and thereby their efficacy as pre-exposure prophylaxis (PrEP) for HIV prevention. Although the role of rectal microbiota in HIV acquisition in women is less well understood, the composition of this compartment's microbiome, particularly the presence of species of bacteria from the Prevotellaceae family likely contribute to HIV acquisition. Advances in technologies have facilitated the study of the genital microbiome's structure and function. While next-generation sequencing advanced knowledge of the diversity and complexity of the vaginal microbiome, the emerging field of metaproteomics, which provides important information on vaginal bacterial community structure, diversity and function, is further shedding light on functionality of the vaginal microbiome and its relationship with bacterial vaginosis (BV), as well as antiretroviral PrEP efficacy.

CONCLUSIONS

A better understanding of the composition, structure and function of the microbiome is needed to identify opportunities to alter the vaginal microbiome and prevent BV and reduce the risk of HIV acquisition.

Vaginal microbiota and susceptibility to HIV

: Bacterial vaginosis, characterized by the replacement of the Lactobacillus-dominant microbiota with anaerobic bacteria and facultative Gram-negative rods, has been associated with adverse reproductive health outcomes including HIV acquisition. With the advent of newer molecular techniques, the vaginal microbiota can be investigated in more detail and the association with HIV examined more thoroughly. This review examines recent evidence suggesting that vaginal dysbiosis with increased microbial diversity, specific vaginal bacterial communities, and the presence and concentrations of some individual bacterial species, may increase HIV susceptibility. Potential mechanisms through which vaginal microbiota could impact HIV susceptibility are discussed. On the basis of the available data, this review finds that there is a modest, but growing, body of evidence linking vaginal microbiota to HIV susceptibility in women. The evidence could be strengthened through two main pathways. First, laboratory studies such as ex-vivo or animal experiments are needed to move from plausible mechanisms towards proven mechanisms that explain an effect of the vaginal microbiota on HIV susceptibility. Second, experimental evidence could directly test the hypothesis that sustaining optimal microbiota reduces HIV risk, though there are important obstacles to conducting such studies. Finally, this review examines strong evidence from a recent publication suggesting that deviations from an optimal vaginal microbiome, and particularly the presence of some bacterial communities with high relative abundance of Gardnerella vaginalis, reduces the efficacy of vaginal tenofovir-based microbicides.

Moral Panic and the Construction of National Order

This article examines some of the major concepts used to model the Thai AIDS epidemic and to direct interventions, in particular, the concepts of discrete risk groups and of the sequential spread of HIV from group to group in a wave-like fashion which, although they have been largely discredited in the international AIDS literature, retain a high degree of currency in Thailand. I argue that Thailand’s HIV/AIDS epidemic had the effect of bringing sexual practices from the private sphere into the public arena, where the concept of risk group rendered visible the social body of modern Thailand as a hierarchy of risk, with specific groups attributed behaviours necessitating control. This notion found enduring favour in Thailand because it reinforced existing social prejudices about members of groups such as the male underclass, prostitutes and injecting drug users, and legitimated the claims of government and non-government organizations for the monitoring and control of these groups. There has been a high level of consensus over this strategy, and a lack of competing discourses. Thus Thai AIDS discourse has not only failed to transcend state and middle-class notions of morality and normativity, but it has also failed to come to terms with Thailand’s changing sexual cultures.

Safety and Pharmacokinetics of Quick-Dissolving Polymeric Vaginal Films Delivering the Antiretroviral IQP-0528 for Preexposure Prophylaxis

For human immunodeficiency virus (HIV) prevention, microbicides or drugs delivered as quick-dissolving films may be more acceptable to women than gels because of their compact size, minimal waste, lack of an applicator, and easier storage and transport. This has the potential to improve adherence to promising products for preexposure prophylaxis. Vaginal films containing IQP-0528, a nonnucleoside reverse transcriptase inhibitor, were evaluated for their pharmacokinetics in pigtailed macaques. Polymeric films (22 by 44 by 0.1 mm; providing 75% of a human dose) containing IQP-0528 (1.5%, wt/wt) with and without poly(lactic-co-glycolic acid) (PLGA) nanoparticle encapsulation were inserted vaginally into pigtailed macaques in a crossover study design (n = 6). With unencapsulated drug, the median (range) vaginal fluid concentrations of IQP-0528 were 160.97 (2.73 to 2,104), 181.79 (1.86 to 15,800), and 484.50 (8.26 to 4,045) μg/ml at 1, 4, and 24 h after film application, respectively. Median vaginal tissue IQP-0528 concentrations at 24 h were 3.10 (0.03 to 222.58) μg/g. The values were similar at locations proximal, medial, and distal to the cervix. The IQP-0528 nanoparticle-formulated films delivered IQP-0528 in vaginal tissue and secretions at levels similar to those obtained with the unencapsulated formulation. A single application of either formulation did not disturb the vaginal microflora or the pH (7.24 ± 0.84 [mean ± standard deviation]). The high mucosal IQP-0528 levels delivered by both vaginal film formulations were between 1 and 5 log higher than the in vitro 90% inhibitory concentration (IC90) of 0.146 μg/ml. The excellent coverage and high mucosal levels of IQP-0528, well above the IC90, suggest that the films may be protective and warrant further evaluation in a vaginal repeated low dose simian-human immunodeficiency virus (SHIV) transmission study in macaques and clinically in women.

The vaginal microbiota, host defence and reproductive physiology

The interaction between the human host and the vaginal microbiota is highly dynamic. Major changes in the vaginal physiology and microbiota over a woman's lifetime are largely shaped by transitional periods such as puberty, menopause and pregnancy, while daily fluctuations in microbial composition observed through culture-independent studies are more likely to be the results of daily life activities and behaviours. The vaginal microbiota of reproductive-aged women is largely made up of at least five different community state types. Four of these community state types are dominated by lactic-acid producing Lactobacillus spp. while the fifth is commonly composed of anaerobes and strict anaerobes and is sometimes associated with vaginal symptoms. The production of lactic acid has been associated with contributing to the overall health of the vagina due to its direct and indirect effects on pathogens and host defence. Some species associated with non-Lactobacillus vaginal microbiota may trigger immune responses as well as degrade the host mucosa, processes that ultimately increase susceptibility to infections and contribute to negative reproductive outcomes such as infertility and preterm birth. Further studies are needed to better understand the functional underpinnings of how the vaginal microbiota affect host physiology but also how host physiology affects the vaginal microbiota. Understanding this fine-tuned interaction is key to maintaining women's reproductive health.

Evaluation of Health Disparity in Bacterial Vaginosis and the Implications for HIV-1 Acquisition in African American Women

There is a health disparity for both bacterial vaginosis (BV) and human immunodeficiency virus type 1 (HIV-1) infection in African American women that may be linked. The evidence that BV predisposes women to higher risk for HIV infection is well documented. The underlying mechanisms to support the epidemiological connections will require further investigations. This review explores the risk factors for BV disease with implications for HIV-1 acquisition in the context of race as a potential driver of the 20-fold increase in HIV-1 acquisition for African American women compared to white women. Specifically, it explores (i) disparities for BV in African American women, (ii) racial disparity for HIV-1 acquisition in African American women, (iii) common factors associated with BV and HIV acquisition in African American women, and (iv) potential mechanisms of the enhancement of HIV-1 transmission by BV.

Bacterial vaginosis: a synthesis of the literature on etiology, prevalence, risk factors, and relationship with chlamydia and gonorrhea infections

Bacterial vaginosis (BV) is a common vaginal disorder in women of reproductive age. Since the initial work of Leopoldo in 1953 and Gardner and Dukes in 1955, researchers have not been able to identify the causative etiologic agent of BV. There is increasing evidence, however, that BV occurs when Lactobacillus spp., the predominant species in healthy vaginal flora, are replaced by anaerobic bacteria, such as Gardenella vaginalis, Mobiluncus curtisii, M. mulieris, other anaerobic bacteria and/or Mycoplasma hominis. Worldwide, it estimated that 20-30 % of women of reproductive age attending sexually transmitted infection (STI) clinics suffer from BV, and that its prevalence can be as high as 50-60 % in high-risk populations (e.g., those who practice commercial sex work (CSW). Epidemiological data show that women are more likely to report BV if they: 1) have had a higher number of lifetime sexual partners; 2) are unmarried; 3) have engaged in their first intercourse at a younger age; 4) have engaged in CSW, and 5) practice regular douching. In the past decade, several studies have provided evidence on the contribution of sexual activity to BV. However, it is difficult to state that BV is a STI without being able to identify the etiologic agent. BV has also emerged as a public health problem due to its association with other STIs, including: human immunodeficiency virus (HIV), herpes simplex virus type 2 (HSV-2), Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). The most recent evidence on the association between BV and CT/NG infection comes from two secondary analyses of cohort data conducted among women attending STI clinics. Based on these studies, women with BV had a 1.8 and 1.9-fold increased risk for NG and CT infection, respectively. Taken together, BV is likely a risk factor or at least an important contributor to subsequent NG or CT infection in high-risk women. Additional research is required to determine whether this association is also present in other low-risk sexually active populations, such as among women in the US military. It is essential to conduct large scale cross-sectional or population-based case-control studies to investigate the role of BV as a risk factor for CT/NG infections. These studies could lead to the development of interventions aimed at reducing the burden associated with bacterial STIs worldwide.

A cross-sectional study of bacterial vaginosis, intravaginal practices and HIV genital shedding; implications for HIV transmission and women's health

OBJECTIVES

Bacterial vaginosis (BV) is associated with an increased risk of HIV transmission, and intravaginal practices (IVP) are an important risk factor for developing BV. The relationship between IVP, BV and HIV lower genital shedding, responsible for HIV transmission, has not been examined in women receiving antiretrovirals in Zambia.

DESIGN

Cross-sectional study.

SETTING

Community Health Center in Lusaka, Zambia.

PARTICIPANTS AND METHODS

Participants were HIV-infected women receiving antiretroviral therapy and engaging in IVP (n=128). Participants completed audio computer-administered self-interviews to assess IVP and underwent a vaginal examination. BV was diagnosed using Nugent criteria. HIV-1 lower genital shedding was assessed by measuring HIV-1 RNA in cervicovaginal lavages.

RESULTS

Most women engaged in IVP daily (114, 89.0%) and 81 (63.3%) of the participants had BV. HIV-1 genital shedding was detected in 18 (14.2%) participants. BV was associated with daily use of IVP (prevalence ratio, PR=4.58, CI 1.26 to 16.64, p=0.02) and weekly use of traditional medicines for IVP (PR=1.33, CI 1.05 to 1.68, p=0.02). The only factor associated with HIV-1 lower genital shedding was plasma viraemia (PR=4.61, CI 2.02 to 10.54, p<0.001). Neither IVP nor BV were associated with HIV shedding.

CONCLUSIONS

Despite the frequency of IVP and high prevalence of BV, plasma viraemia was the primary factor associated with HIV lower genital shedding. These findings support early initiation of antiretrovirals as an HIV prevention tool. Given adverse health outcomes associated with BV, the association between frequent IVP and BV, and the powerful local norms and traditions encouraging IVP, there is a need for studies assessing culturally tailored interventions to decrease BV in high-prevalence settings.

Bacterial Vaginosis and Subclinical Markers of Genital Tract Inflammation and Mucosal Immunity

Bacterial vaginosis (BV) has been linked to an increased risk of human immunodeficiency virus (HIV) acquisition and transmission in observational studies, but the underlying biological mechanisms are unknown. We measured biomarkers of subclinical vaginal inflammation, endogenous antimicrobial activity, and vaginal flora in women with BV and repeated sampling 1 week and 1 month after completion of metronidazole therapy. We also compared this cohort of women with BV to a healthy control cohort without BV. A longitudinal, open label study of 33 women with a Nugent score of 4 or higher was conducted. All women had genital swabs, cervicovaginal lavage (CVL) fluid, and cervicovaginal biopsies obtained at enrollment and received 7 days of metronidazole treatment. Repeat sampling was performed approximately 1 week and 1 month after completion of therapy. Participant's baseline samples were compared to a healthy, racially matched control group (n=13) without BV. The CVL from women with resolved BV (Nugent 0-3) had significantly higher anti-HIV activity, secretory leukocyte protease inhibitor (SLPI), and growth-related oncogene alpha (GRO-α) levels and their ectocervical tissues had significantly more CD8 cells in the epithelium. Women with persistent BV after treatment had significantly higher levels of interleukin-1β, tumor necrosis factor alpha (TNF-α), and intercellular adhesion molecule 1 (ICAM-1) in the CVL. At study entry, participants had significantly greater numbers of CCR5(+) immune cells and a higher CD4/CD8 ratio in ectocervical tissues prior to metronidazole treatment, compared to a racially matched cohort of women with a Nugent score of 0-3. These data indicate that BV is associated with changes in select soluble immune mediators, an increase in HIV target cells, and a reduction in endogenous antimicrobial activity, which may contribute to the increased risk of HIV acquisition.

Establishment of a sensitive system for analysis of human vaginal microbiota on the basis of rRNA-targeted reverse transcription-quantitative PCR

Ten specific primer sets, for Lactobacillus gasseri, Lactobacillus crispatus, Atopobium vaginae, Gardnerella vaginalis, Mobiluncus curtisii, Chlamydia trachomatis/muridarum, Bifidobacterium longum subsp. longum, Bifidobacterium longum subsp. infantis, Bifidobacterium adolescentis, and Bifidobacterium angulatum, were developed for quantitative analysis of vaginal microbiota. rRNA-targeted reverse transcription-quantitative PCR (RT-qPCR) analysis of the vaginal samples from 12 healthy Japanese volunteers using the new primer sets together with 25 existing primer sets revealed the diversity of their vaginal microbiota: Lactobacilli such as L. crispatus, L. gasseri, Lactobacillus jensenii, Lactobacillus iners, and Lactobacillus vaginalis, as the major populations at 10(7) cells/ml vaginal fluid, were followed by facultative anaerobes such as Streptococcus and strict anaerobes at lower population levels of 10(4) cells/ml or less. Certain bacterial vaginosis (BV)-related bacteria, such as G. vaginalis, A. vaginae, M. curtisii, and Prevotella, were also detected in some subjects. Especially in one subject, both G. vaginalis and A. vaginae were detected at high population levels of 10(8.8) and 10(8.9) cells/ml vaginal fluid, suggesting that she is an asymptomatic BV patient. These results suggest that the RT-qPCR system is effective for accurate analysis of major vaginal commensals and diagnosis of several vaginal infections.

Poly(ethylene glycol) (PEG)-lactic acid nanocarrier-based degradable hydrogels for restoring the vaginal microenvironment

Women with bacterial vaginosis (BV) display reduced vaginal acidity, which make them susceptible to associated infections such as HIV. In the current study, poly(ethylene glycol) (PEG) nanocarrier-based degradable hydrogels were developed for the controlled release of lactic acid in the vagina of BV-infected women. PEG-lactic acid (PEG-LA) nanocarriers were prepared by covalently attaching lactic acid to 8-arm PEG-SH via cleavable thioester bonds. PEG-LA nanocarriers with 4 copies of lactic acid per molecule provided controlled release of lactic acid with a maximum release of 23% and 47% bound lactic acid in phosphate buffered saline (PBS, pH7.4) and acetate buffer (AB, pH4.3), respectively. The PEG nanocarrier-based hydrogels were formed by cross-linking the PEG-LA nanocarriers with 4-arm PEG-NHS via degradable thioester bonds. The nanocarrier-based hydrogels formed within 20 min under ambient conditions and exhibited an elastic modulus that was 100-fold higher than the viscous modulus. The nanocarrier-based degradable hydrogels provided controlled release of lactic acid for several hours; however, a maximum release of only 10%-14% bound lactic acid was observed possibly due to steric hindrance of the polymer chains in the cross-linked hydrogel. In contrast, hydrogels with passively entrapped lactic acid showed burst release with complete release within 30 min. Lactic acid showed antimicrobial activity against the primary BV pathogen Gardnerella vaginalis with a minimum inhibitory concentration (MIC) of 3.6 mg/ml. In addition, the hydrogels with passively entrapped lactic acid showed retained antimicrobial activity with complete inhibition G. vaginalis growth within 48 h. The results of the current study collectively demonstrate the potential of PEG nanocarrier-based hydrogels for vaginal administration of lactic acid for preventing and treating BV.

Mucosal immunity in the female genital tract, HIV/AIDS

Mucosal immunity consists of innate and adaptive immune responses which can be influenced by systemic immunity. Despite having been the subject of intensive studies, it is not fully elucidated what exactly occurs after HIV contact with the female genital tract mucosa. The sexual route is the main route of HIV transmission, with an increased risk of infection in women compared to men. Several characteristics of the female genital tract make it suitable for inoculation, establishment of infection, and systemic spread of the virus, which causes local changes that may favor the development of infections by other pathogens, often called sexually transmitted diseases (STDs). The relationship of these STDs with HIV infection has been widely studied. Here we review the characteristics of mucosal immunity of the female genital tract, its alterations due to HIV/AIDS, and the characteristics of coinfections between HIV/AIDS and the most prevalent STDs.

Vaginal microbiota and its role in HIV transmission and infection

The urogenital tract appears to be the only niche of the human body that shows clear differences in microbiota between men and women. The female reproductive tract has special features in terms of immunological organization, an epithelial barrier, microbiota, and influence by sex hormones such as estrogen. While the upper genital tract is regarded as free of microorganisms, the vagina is colonized by bacteria dominated by Lactobacillus species, although their numbers vary considerably during life. Bacterial vaginosis is a common pathology characterized by dysbiosis, which increases the susceptibility for HIV infection and transmission. On the other hand, HIV infections are often characterized by a disturbed vaginal microbiota. The endogenous vaginal microbiota may protect against HIV by direct production of antiviral compounds, through blocking of adhesion and transmission by ligands such as lectins, and/or by stimulation of immune responses. The potential role of probiotics in the prevention of HIV infections and associated symptoms, by introducing them to the vaginal and gastrointestinal tract (GIT), is also discussed. Of note, the GIT is a site of considerable HIV replication and CD4(+) T-cell destruction, resulting in both local and systemic inflammation. Finally, genetically engineered lactobacilli show promise as new microbicidal agents against HIV.

Performance of BVBlue rapid test in detecting bacterial vaginosis among women in Mysore, India

Bacterial vaginosis (BV) is the most common cause of abnormal vaginal discharge in reproductive age women. It is associated with increased susceptibility to HIV/STI and adverse birth outcomes. Diagnosis of BV in resource-poor settings like India is challenging. With little laboratory infrastructure there is a need for objective point-of-care diagnostic tests. Vaginal swabs were collected from women 18 years and older, with a vaginal pH>4.5 attending a reproductive health clinic. BV was diagnosed with Amsel's criteria, Nugent scores, and the OSOM BVBlue test. Study personnel were blinded to test results. There were 347 participants enrolled between August 2009 and January 2010. BV prevalence was 45.1% (95% confidence interval (CI): 41.5%-52.8%) according to Nugent score. When compared with Nugent score, the sensitivity, specificity, positive predictive value, negative predictive value for Amsel's criteria and BVBlue were 61.9%, 88.3%, 81.5%, 73.7% and 38.1%, 92.7%, 82.1%, 63.9%, respectively. Combined with a "whiff" test, the performance of BVBlue increased sensitivity to 64.4% and negative predictive value to 73.8%. Despite the good specificity, poor sensitivity limits the usefulness of the BVBlue as a screening test in this population. There is a need to examine the usefulness of this test in other Indian populations.

Microbiota and pelvic inflammatory disease

Female genital tract microbiota play a crucial role in maintaining health. Disequilibrium of the microbiota has been associated with increased risk of pelvic infections. In recent years, culture-independent molecular techniques have expanded understanding of the composition of genital microbiota and the dynamic nature of the microbiota. There is evidence that upper genital tract may not be sterile and may harbor microflora in the physiologic state. The isolation of bacterial vaginosis-associated organisms in women with genital infections establishes a link between pelvic infections and abnormal vaginal flora. With the understanding of the composition of the microbiota in healthy and diseased states, the next logical step is to identify the function of the newly identified microbes. This knowledge will further expand our understanding of the causation of pelvic infections, which may lead to more effective prevention and treatment strategies.

Hormonal contraception is associated with a reduced risk of bacterial vaginosis: a systematic review and meta-analysis

Objective

To examine the association between hormonal contraception (HC) and bacterial vaginosis (BV) by systematic review and meta-analysis.

Methods

Medline, Web of Science and Embase databases were searched to 24/1/13 and duplicate references removed. Inclusion criteria 1) >20 BV cases; 2) accepted BV diagnostic method; 3) measure of HC-use either as combined oestrogen-progesterone HC (combined), progesterone-only contraception (POC) or unspecified HC (u-HC); 4) ≥10% of women using HC; 5) analysis of the association between BV and HC-use presented; 6) appropriate control group. Data extracted included: type of HC, BV diagnostic method and outcome (prevalent, incident, recurrent), and geographical and clinic-setting. Meta-analyses were conducted to calculate pooled effect sizes (ES), stratified by HC-type and BV outcome. This systematic review is registered with PROSPERO (CRD42013003699).

Results

Of 1713 unique references identified, 502 full-text articles were assessed for eligibility and 55 studies met inclusion criteria. Hormonal contraceptive use was associated with a significant reduction in the odds of prevalent BV (pooled effect size by random-effects [reES] = 0.68, 95%CI0.63–0.73), and in the relative risk (RR) of incident (reES = 0.82, 95%CI:0.72–0.92), and recurrent (reES = 0.69, 95%CI:0.59–0.91) BV. When stratified by HC-type, combined-HC and POC were both associated with decreased prevalence of BV and risk of incident BV. In the pooled analysis of the effect of HC-use on the composite outcome of prevalent/incident/recurrent BV, HC-use was associated with a reduced risk of any BV (reES = 0.78, 95%CI:0.74–0.82).

Conclusion

HC-use was associated with a significantly reduced risk of BV. This negative association was robust and present regardless of HC-type and evident across all three BV outcome measures. When stratified by HC-type, combined-HC and POC were both individually associated with a reduction in the prevalence and incidence of BV. This meta-analysis provides compelling evidence that HC-use influences a woman’s risk of BV, with important implications for clinicians and researchers in the field.

Hormonal contraception decreases bacterial vaginosis but oral contraception may increase candidiasis: implications for HIV transmission

OBJECTIVE

A 2012 WHO consultation concluded that combined oral contraception (COC) does not increase HIV acquisition in women, but the evidence for depot medroxyprogesterone acetate (DMPA) is conflicting. We evaluated the effect of COC and DMPA use on the vaginal microbiome because current evidence suggests that any deviation from a 'healthy' vaginal microbiome increases women's susceptibility to HIV.

METHODS

We conducted a systematic review and reanalysed the Hormonal Contraception and HIV Acquisition (HC-HIV) study. Vaginal microbiome outcomes included bacterial vaginosis by Nugent scoring, vaginal candidiasis by culture or KOH wet mount and microbiome compositions as characterized by molecular techniques.

RESULTS

Our review of 36 eligible studies found that COC and DMPA use reduce bacterial vaginosis by 10-20 and 18-30%, respectively. The HC-HIV data showed that COC and DMPA use also reduce intermediate microbiota (Nugent score of 4-6) by 11% each. In contrast, COC use (but not DMPA use) may increase vaginal candidiasis. Molecular vaginal microbiome studies (n=4) confirm that high oestrogen levels favour a vaginal microbiome composition dominated by 'healthy' Lactobacillus species; the effects of progesterone are less clear and not well studied.

CONCLUSION

DMPA use does not increase HIV risk by increasing bacterial vaginosis or vaginal candidiasis. COC use may predispose for vaginal candidiasis, but is not believed to be associated with increased HIV acquisition. However, the potential role of Candida species, and vaginal microbiome imbalances other than bacterial vaginosis or Candida species, in HIV transmission cannot yet be ruled out. Further in-depth molecular studies are needed.

Bacterial vaginosis and risk for Trichomonas vaginalis infection: a longitudinal analysis

BACKGROUND

Bacterial vaginosis (BV) and Trichomonas vaginalis (TV) have been estimated to affect one-quarter to one-third of sexually active women worldwide, and are often found concurrently. Few studies have examined this relationship longitudinally to better understand the direction and temporality of this association.

METHODS

Between 2005 and 2006, a cohort of 853 young, sexually active women was followed in Mysore, India; participants were interviewed and tested for BV and TV at baseline, and at 3- and 6-month visit. Generalized estimating equations were used to estimate how changes in vaginal flora between consecutive visits-as defined by Nugent diagnostic criteria for BV-were related to the risk of TV infection at the latter visit, adjusted for sociodemographic and behavioral covariates. Treatment was offered to women with TV and/or symptomatic BV.

RESULTS

After adjustment for covariates, participants with abnormal vaginal flora at 2 consecutive visits had 9 times higher risk of TV (95% CI: 4.1, 20.0) at the latter visit, relative to those with persistently normal flora. An increased risk of TV was also observed for participants whose flora status changed from normal to abnormal (adjusted risk ratio: 7.11, 95% CI: 2.8, 18.2) and from abnormal to normal (adjusted risk ratio: 4.50, 95% CI: 1.7, 11.8).

CONCLUSIONS

Women experiencing abnormal flora during a 3-month span appear to have significantly increased risk of acquiring TV infection. Women of reproductive age in low-resource settings found to have abnormal vaginal flora should be assessed for TV.

In captive rhesus macaques, cervicovaginal inflammation is common but not associated with the stable polymicrobial microbiome

Vaginal inoculation of rhesus macaques (RM) with simian immunodeficiency virus (SIV) has been used to study the biology of HIV transmission. Although the results of vaginal SIV transmission experiments could be affected by vaginal inflammation, studies to date have been conducted without regard to levels of pre-existing genital inflammation present in RM. We collected cevicovaginal secretions (CVS) from 33–36 RM during the mid menstrual cycle (day 10–20) at 2 time points approximately 8 months apart and characterized the mRNA and protein levels of inflammatory cytokines, chemokines and interferon-stimulated genes. There was extreme variability in the levels of inflammatory mediators (IFN-α, IFN-γ, IL-6, TNF, IL-1b, IP-10, MIG, IL-12 and IL-17). In most animals, the mRNA levels of the inflammatory mediators were similar in the 2 CVS samples collected 8 months apart, suggesting that genital inflammation is stable in a subset of captive female RM. At both time points the cervicovaginal microbiota had low levels of Lactobacillus and was relatively diverse with an average of 13 genera in the samples from the first time point (median 13, range 7–21) and an average of 11.5 genera in the samples from the second time point (median 11, range 5–20). Many of the macaques had similar microbiota in the samples collected 8 months apart. However, we found no correlation between specific bacterial genera and the mRNA or protein levels of the inflammatory mediators in the genital tract of RM in this study. It seems likely that results of published vaginal SIV transmission experiments in RM have been influenced by pre-existing inflammation in the animals used for the experiments.

Diaphragm used with replens gel and risk of bacterial vaginosis: results from a randomized controlled trial

BACKGROUND

Bacterial vaginosis (BV) has been linked to female HIV acquisition and transmission. We investigated the effect of providing a latex diaphragm with Replens and condoms compared to condom only on BV prevalence among participants enrolled in an HIV prevention trial.

METHODS

We enrolled HIV-seronegative women and obtained a vaginal swab for diagnosis of BV using Nugent's criteria; women with BV (score 7-10) were compared to those with intermediate (score 4-6) and normal flora (score 0-3). During quarterly follow-up visits over 12-24 months a vaginal Gram stain was obtained. The primary outcome was serial point prevalence of BV during followup.

RESULTS

528 participants were enrolled; 213 (40%) had BV at enrollment. Overall, BV prevalence declined after enrollment in women with BV at baseline (OR = 0.4, 95% CI 0.29-.56) but did not differ by intervention group. In the intention-to-treat analysis BV prevalence did not differ between the intervention and control groups for women who had BV (OR = 1.01, 95% CI 0.52-1.94) or for those who did not have BV (OR = 1.21, 95% CI 0.65-2.27) at enrollment. Only 2.1% of participants were treated for symptomatic BV and few women (5-16%) were reported using anything else but water to cleanse the vagina over the course of the trial.

CONCLUSIONS

Provision of the diaphragm, Replens, and condoms did not change the risk of BV in comparison to the provision of condoms alone.

Inhibition of HIV and HSV infection by vaginal lactobacilli in vitro and in vivo

BACKGROUND AND THE PURPOSE OF THE STUDY

The cervico-vaginal mucosa which is populated with microflora (mostly includes lactobacilli) is the portal of entry for sexually transmitted pathogens.

METHODS

The in vitro anti-viral effect of vaginal and non-vaginal lactobacillus was evaluated using single cycle HIV-1 replication and HSV-2 plaque reduction assays. The XTT proliferation assay was used to monitor the cellular toxicity. The in vivo anti-HSV-1 activity was evaluated in BALB/c mouse model by monitoring skin lesion and immune response development.

RESULTS AND MAJOR CONCLUSION

DMEM culture supernatant of L. Gasseri and L. fermentum (PH 7.3) did not show toxic effect but inhibited 50% of HIV replication at 12 and 31% concentrations, respectively. Co-culture of L. gasseri (1000 CFU/ target cell) showed mild cytotoxicity but inhibited 68% of HIV replication. The supernatant of L. crispatus inhibited 50% of HSV replication at 4% and also co-culture of L. gasseri, L. rhamnosus and L. crispatus revokes almost all of the HSV multiplication. Culture supernatants of L. gasseri and L. crispatus had significant virucidal effect against the HIV and HSV and inhibited HSV infection in a stage before viral entry to the target cells. Alive L. gasseri cells showed high potential for inhibiting HSV-1 infection in vivo condition. Current data indicates that lactobacilli supernatant encompasses components with neutralizing activity against HIV and HSV and it would be a determinant factor for viral diseases transmission and promising lead for anti-viral probiotic design.

Vaginal microbiome: rethinking health and disease

Vaginal microbiota form a mutually beneficial relationship with their host and have a major impact on health and disease. In recent years our understanding of vaginal bacterial community composition and structure has significantly broadened as a result of investigators using cultivation-independent methods based on the analysis of 16S ribosomal RNA (rRNA) gene sequences. In asymptomatic, otherwise healthy women, several kinds of vaginal microbiota exist, the majority often dominated by species of Lactobacillus, while others are composed of a diverse array of anaerobic microorganisms. Bacterial vaginosis is the most common vaginal condition and is vaguely characterized as the disruption of the equilibrium of the normal vaginal microbiota. A better understanding of normal and healthy vaginal ecosystems that is based on their true function and not simply on their composition would help better define health and further improve disease diagnostics as well as the development of more personalized regimens to promote health and treat diseases.

The role of bacterial vaginosis and trichomonas in HIV transmission across the female genital tract

Bacterial vaginosis (BV) and Trichomonas vaginalis (TV) infections are both very common and are associated with increased risk of sexual transmission of HIV. There are several mechanisms by which BV and TV could affect susceptibility including inducing pro-inflammatory cytokines and disrupting mucosal barrier function. This review highlights recent advances in our understanding of how these genital conditions lead to an increased risk of HIV infection in women.

Severity of bacterial vaginosis and the risk of sexually transmitted infection

OBJECTIVE

The purpose of this study was to determine whether the association between bacterial vaginosis (BV) and incident sexually transmitted infection (STI) varies with more extreme BV scores.

STUDY DESIGN

We analyzed the data from 535 women who were enrolled in a randomized trial to promote dual method contraceptive use. Incident STI was defined as any case of Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, or pelvic inflammatory disease. BV was defined by Gram stain (Nugent score). STI risk was estimated with the use of proportional hazards regression.

RESULTS

Binary (0-6 vs 7-10) and 3-level (negative 0-3, intermediate 4-6, or BV 7-10) categorizations were not associated with time to STI; however, women with the highest Nugent scores (9-10) had a 2.1-fold increased risk of STI (95% confidence interval, 1.05-4.28), compared with women with normal flora.

CONCLUSION

Nugent score>8 is associated with incident STI. More accurate classification of BV will allow clinicians to identify those women who are at greatest risk of STI.

Innate immunity and inflammatory response to Trichomonas vaginalis and bacterial vaginosis: relationship to HIV acquisition

Most women contract HIV-1 through sexual intercourse with an infected partner. Highly prevalent, unreported and often asymptomatic lower genital tract infections, including bacterial vaginosis (BV) and trichomoniasis (Trichomonas vaginalis- TV), increase a woman's susceptibility to HIV-1 genital infection, given an exposure. A review of the literature from 1989 to the present was conducted. This article will review potential mechanisms by which BV and TV serve as HIV-1-enhancing cofactors including (i) initiation of a clinical or subclinical mucosal inflammatory response, (ii) alteration of innate mucosal immunity, (iii) alteration of normal vaginal microflora and pH, and (iv) weakening or breach of intact cervico-vaginal mucosa. The transmission of HIV-1, in the absence of cofactors, is poorly efficient. Understanding the mechanisms by which these infections enhance HIV-1 acquisition is important to designing effective, safe and evidence-based prevention modalities.

Phase 2a study assessing colonization efficiency, safety, and acceptability of Lactobacillus crispatus CTV-05 in women with bacterial vaginosis

BACKGROUND

Bacterial vaginosis (BV) is a common vaginal infection caused by a lack of endogenous lactobacilli and overgrowth of pathogens that frequently recurs following antibiotic treatment.

METHODS

A phase 2a study assessed colonization efficiency, safety, tolerability, and acceptability of Lactobacillus crispatus CTV-05 (LACTIN-V) administered by a vaginal applicator. Twenty-four women with BV were randomized in a 3:1 ratio of active product to placebo. Participants used LACTIN-V at 2 × 10 colony-forming units (cfu)/dose or placebo for 5 initial consecutive days, followed by a weekly application over 2 weeks. They returned for follow-up on Days 10 and 28.

RESULTS

Sixty-one percent of the 18 women randomized to the LACTIN-V group were colonized with L. crispatus CTV-05 at Day 10 or Day 28. Among LACTIN-V users with complete adherence to the study regimen, 78% were colonized at Day 10 or Day 28. Of the 120 adverse events (AEs) that occurred, 108 (90%) and 12 (10%) were of mild and moderate severity, respectively. AEs were evenly distributed between the LACTIN-V and placebo group. Of the total AEs, 93 (78%) were genitourinary in origin. The most common genitourinary AEs included vaginal discharge (46%), abdominal pain (46%), dysuria (21%), pollakiuria (21%), vaginal odor (21%), and genital pruritus (17%). No grade 3 or 4 AEs or serious AEs occurred and no deep epithelial disruption was seen during colposcopic evaluation. The product was well tolerated and accepted.

CONCLUSIONS

LACTIN-V colonized well, and was safe and acceptable in women treated for BV.

Periodontal disease and bacterial vaginosis as genetic and environmental markers for the risk of spontaneous preterm labor and preterm birth

OBJECTIVE

The aim of this study was to review the evidence associating periodontal disease, and bacterial vaginosis with preterm birth, and the link with gene polymorphism, as well as the preventions and interventions which might reduce the risk of spontaneous preterm labor and preterm births in women with periodontal disease and/or bacterial vaginosis.

BACKGROUND

Preterm birth accounts for 70% of perinatal mortality, nearly 50% of long term neurological morbidity, and a significant impact on health care costs. There is evidence that spontaneous preterm labor and preterm birth are associated with intrauterine infection due to abnormal genital and/or oral colonization. Periodontal disease and bacterial vaginosis share microbiological similarities, and both conditions are associated with spontaneous preterm labor and preterm birth. In addition, periodontal disease and bacterial vaginosis have been linked through gene polymorphism.

METHODS

A review of the literature using widely accepted scientific search engines in English language.

RESULTS

Studies evaluating antibiotic administration to eradicate periodontal disease and/or bacterial vaginosis responsible organisms, and minimize the risk of preterm births have yielded conflicting results. With respect to bacterial vaginosis, the timing and the choice of antibiotic administration might partly explain the conflicting results. The use of scaling and/or root planning for women with periodontal disease appears to reduce the risk of preterm birth, but routine administration of antibiotics has not demonstrated any impact on preterm birth.

CONCLUSION

Prospective studies evaluating the association of gene polymorphism with preterm birth, and the contribution of periodontal disease and bacterial vaginosis are needed.

The vaginal microbiome: new information about genital tract flora using molecular based techniques

Vaginal microbiome studies provide information that may change the way we define vaginal flora. Normal flora appears dominated by one or two species of Lactobacillus. Significant numbers of healthy women lack appreciable numbers of vaginal lactobacilli. Bacterial vaginosis (BV) is not a single entity, but instead consists of different bacterial communities or profiles of greater microbial diversity than is evident from cultivation-dependent studies. BV should be considered a syndrome of variable composition that results in different symptoms, phenotypical outcomes, and responses to different antibiotic regimens. This information may help to elucidate the link between BV and infection-related adverse outcomes of pregnancy.

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.

Pyrosequencing of the genital microbiotas of HIV-seropositive and -seronegative women reveals Lactobacillus iners as the predominant Lactobacillus Species

The species of vaginal lactobacilli in HIV-seropositive and -seronegative women were determined by 16S gene pyrosequencing. Lactobacillus iners sequences were the predominant lactobacillus sequences in 66% of HIV(+) women and 90% of HIV(-) women. This has implications for resistance of HIV(+) and HIV(-) women to genital colonization by pathogenic organisms.

Bacterial vaginosis: a cause of infertility?

Bacterial vaginosis (BV) is a common disorder of the genital tract in women characterized by an alteration of the normal acidic lactobacilli-predominant vaginal ecosystem to a vaginal environment dominated by Gardnerella vaginalis, mycoplasma species and anaerobes, with an increase in pH. The present study evaluated whether BV is associated with reproductive complications in women. BV was screened with a Gram stain of vaginal smear and interpretation was done using the Nugent score. Wet mount and polymerase chain reaction were used to screen other infections. Among 510 enrolled women, 72 (14.1%) had BV. Statistical analysis between the BV negative and positive population revealed a significant association (P = 0.0001) with infertility. In pregnant women, the infection rate was low (P = 0.01). Multiple infections such as Candida, Chlamydia and human papilloma virus were observed in 4.2%, 15.3% and 8.3% of BV-infected women, respectively. Results suggest that BV infection is associated with infertility and its absence leads to pregnancy, emphasizing its screening and treatment.

Purification and characterization of enterocin 62-6, a two-peptide bacteriocin produced by a vaginal strain of Enterococcus faecium: Potential significance in bacterial vaginosis

A bacteriocin produced by a vaginal isolate of Enterococcus faecium strain 62-6, designated enterocin 62-6, was characterized following purification and DNA sequence analysis and compared to previously described bacteriocins. Enterocin 62-6 was isolated from brain heart infusion (BHI) culture supernatants using ammonium sulfate precipitation followed by elution from a Sepharose cation exchange column using a continuous salt gradient (0.1-0.7 M NaCl). SDS-PAGE of an active column fraction resulted in an electrophoretically pure protein, which corresponded to the growth inhibition of the sensitive Lactobacillus indicator strain in the gel overlay assay. Purified enterocin 62-6 was shown to be heat- and pH-stable, and sensitive to the proteolytic enzymes alpha-chymotrypsin and pepsin. Results from mass spectrometry suggested that it comprised two peptides of 5206 and 5219+/-1 Da, which was confirmed by DNA sequence analysis. The characteristics of enterocin 62-6 as a small, heat- and pH-stable, cationic, hydrophobic, two-peptide, plasmid-borne bacteriocin, with an inhibitory spectrum against a broad range of Gram-positive but not Gram-negative bacteria, were consistent with its classification as a class IIc bacteriocin. Furthermore, its wide spectrum of growth inhibitory activity against Gram-positive bacteria of vaginal origin including lactobacilli, and stability under the acidic conditions of the vagina, are consistent with our hypothesis that it could have potential significance in disrupting the ecology of the vaginal tract and pave the way for the establishment of the abnormal microbiota associated with the vaginal syndrome bacterial vaginosis. This is the first class IIc bacteriocin produced by a strain of E. faecium of vaginal origin to be characterized.

[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.

Can bacterial vaginosis help to find sexually transmitted diseases, especially chlamydial cervicitis?

This study was undertaken to establish reliable factors in order to identify chlamydial cervicitis among suspicious patients. Between January and December 2007, 406 patients who were suspected to have cervicitis due to clinical symptoms, were tested with polymerase chain reaction (PCR) for Chlamydia trachomatis (CT), vaginal pH and Nugent score (NS) in our University hospital and related clinics. During the same period, 67 patients who were diagnosed as having other sexually transmitted diseases (Neisseria gonorrhoeae (NG), Trichomonas vaginalis, Condyloma acuminatum and genital herpes) were also made to participate in this study. Eighty-nine women (22%) were positive for CT PCR. Bacterial vaginosis (BV)-positive women were tested positive for CT PCR (75/288), significantly higher than those without BV (6/66, P = 0.01). In addition, under 20-years old women were positive for CT PCR (24/57), significantly higher than those who were over 30 years old (16/113, P = 0.001). The proportion of patients with high NS (>7) in CT, NG and T. vaginalis cases were 75/89 (84.3%), 22/27 (81.5%) and 11/14 (78.6%), respectively. Whereas the high NS of the C. acuminatum and genital herpes groups were recorded at 7/14 (50%) and 4/12 (33.3%), respectively. Younger women with BV could be at a higher risk for STDs, especially for CT cervicitis.

Antibody-based detection and inhibition of vaginolysin, the Gardnerella vaginalis cytolysin

Bacterial vaginosis (BV) is the most common vaginal infection worldwide and is associated with significant adverse sequelae. We have recently characterized vaginolysin (VLY), the human-specific cytotoxin produced by Gardnerella vaginalis and believed to play a critical role in the pathogenesis of BV and its associated morbidities. We hypothesize that novel antibody-based strategies may be useful for detection of VLY and for inhibition of its toxic effects on human cells. Using purified toxin as an immunogen, we generated polyclonal rabbit immune serum (IS) against VLY. A western blot of G. vaginalis lysate was probed with IS and a single band (57 kD) identified. Immunofluorescence techniques using IS detected VLY production by G. vaginalis. In addition, we have developed a sandwich ELISA assay capable of VLY quantification at ng/ml concentrations in the supernatant of growing G. vaginalis. To investigate the potential inhibitory role of IS on VLY-mediated cell lysis, we exposed human erythrocytes to VLY or VLY pretreated with IS and determined the percent hemolysis. Pretreatment with IS resulted in a significant reduction in VLY-mediated lysis. Similarly, both human cervical carcinoma cells and vaginal epithelial cells exhibited reduced cytolysis following exposure to VLY with IS compared to VLY alone. These results confirm that antibody-based techniques are an effective means of VLY detection. Furthermore, VLY antiserum functions as an inhibitor of VLY–CD59 interaction, mitigating cell lysis. These strategies may have a potential role in the diagnosis and treatment of BV.