Levels of vaginal secretory leukocyte protease inhibitor are decreased in women with lower reproductive tract infections

The possible pathogenic mechanisms of microorganisms in infertility: a narrative review

Infertility can harm a patient in physical, psychological, spiritual, and medical ways. This illness is unusual because it affects the patient's companion and the patient individually. Infertility is a multifactorial disease, and various etiological factors like infection are known to develop this disorder. Recently published studies reported that different bacteria, such as Chlamydia trachomatis, Mycoplasma spp., Ureaplasma urealyticum, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, can lead to infertility by immunopathological effects, oxidative stress, and adverse effects on sperm concentration, motility, morphology, and DNA condensation. Among viruses, Human papillomavirus and Herpes simplex virus reduce sperm progressive motility and sperm concentration. The viruses can lead to the atrophy of the germinal epithelium and degenerative changes in the testes. Candida albicans also harm sperm quality, motility, and chromatin integrity and induce apoptosis in sperm cells. Finally, Trichomonas vaginalis leads to distorted heads, broken necks, and acrosomes exocytosis in sperms. This parasite decreases sperm viability and functional integrity. Noteworthy, oxidative stress could have a role in many pathological changes in the reproductive system. Recent findings show that microorganisms can increase reactive oxygen species concentration inside the host cells, leading to oxidative stress and sperm distress and dysfunction. Therefore, this article explores the potential significance of critical bacteria linked to infertility and their pathogenic mechanisms that can affect sperm function and the female reproductive system.

Advances in mass spectrometry technologies to characterize cervicovaginal microbiome functions that impact spontaneous preterm birth

Preterm birth (PTB) is a leading cause of morbidity and mortality in young children. Infection is a major cause of this adverse outcome, particularly in PTBs characterised by spontaneous rupture of membranes, referred to as spontaneous (s)PTB. However, the aetiology of sPTB is not well defined and specific bacteria associated with sPTB differ between studies and at the individual level. This may be due to many factors including a lack of understanding of strain-level differences in bacteria that influence how they function and interact with each other and the host. Metaproteomics and metabolomics are mass spectrometry-based methods that enable the collection of detailed microbial and host functional information. Technological advances in this field have dramatically increased the resolution of these approaches, enabling the simultaneous detection of thousands of proteins or metabolites. These data can be used for taxonomic analysis of vaginal bacteria and other microbes, to understand microbiome-host interactions, and identify diagnostic biomarkers or therapeutic targets. Although these methods have been used to assess host proteins and metabolites, few have characterized the microbial compartment in the context of pregnancy. The utilisation of metaproteomic and metabolomic-based approaches has the potential to vastly improve our understanding of the mechanisms leading to sPTB.

Modeling mucus physiology and pathophysiology in human organs-on-chips

The surfaces of human internal organs are lined by a mucus layer that ensures symbiotic relationships with commensal microbiome while protecting against potentially injurious environmental chemicals, toxins, and pathogens, and disruption of this layer can contribute to disease development. Studying mucus biology has been challenging due to the lack of physiologically relevant human in vitro models. Here we review recent progress that has been made in the development of human organ-on-a-chip microfluidic culture models that reconstitute epithelial tissue barriers and physiologically relevant mucus layers with a focus on lung, colon, small intestine, cervix and vagina. These organ-on-a-chip models that incorporate dynamic fluid flow, air-liquid interfaces, and physiologically relevant mechanical cues can be used to study mucus composition, mechanics, and structure, as well as investigate its contributions to human health and disease with a level of biomimicry not possible in the past.

Host and Microbiome Interplay Shapes the Vaginal Microenvironment

The female reproductive tract harbors a unique microbiome, especially the vagina. The human vaginal microbiome exhibits a low diversity and is dominated by Lactobacillus species, compared to the microbiome of other organs. The host and vaginal microbiome mutually coexist in the vaginal microenvironment. Host cells provide Lactobacillus glycogen as an energy source, and Lactobacillus produce lactic acid, which lowers vaginal pH thereby preventing growth of other bacteria. Bacterial vaginosis can modulate host immune systems, and is frequently associated with various aspects of disease, including sexually transmitted infection, gynecologic cancer, and poor pregnancy outcomes. Because of this, numerous studies focused on the impact of the vaginal microbiome on women`s health and disease. Furthermore, numerous epidemiologic studies also have demonstrated various host factors regulate the vaginal microbiome. The female reproductive tract undergoes constant fluctuations due to hormonal cycle, pregnancy, and other extrinsic factors. Depending on these fluctuations, the vaginal microbiome composition can shift temporally and dynamically. In this review, we highlight the current knowledge of how host factors modulate vaginal microbiome composition and how the vaginal microbiome contributes to maintaining homeostasis or inducing pathogenesis. A better understanding of relationship between host and vaginal microbiome could identify novel targets for diagnosis, prognosis, or treatment of microbiome-related diseases.

The effect of anterior uterocervical angle (aUCA) and cervical length on the development of pelvic inflammatory disease

This study aims to compare the uterine body longitudinal axis, uterine body transverse axis, uterine cervix longitudinal axis and anterior cervical axis angle measured ultrasonographically between women with pelvic inflammatory disease (PID) and healthy controls. Women aged 18-45 years with PID and healthy controls were included in the study. Demographic characteristics, uterine body long axis, uterine body transverse axis, uterine cervix long axis and anterior cervical axis angle of PID patients and healthy controls were evaluated. Gravida, parity, history of smoking were significantly higher in the PID group (n = 75) than the control group (n = 74). The uterine body longitudinal axis (p = 0.001) and transverse axis (p = 0.005) were significantly lower, and the cervix longitudinal axis (p < 0.001) and the anterior uterocervical angle (p < 0.001) were significantly higher in the PID group than the control group. Binary logistic regression analysis showed that uterine body (UTX) longitudinal axis (p = 0.005), uterine cervix longitudinal axis (p < 0.001) and UCA (p < 0.001) were significant predictors of PID. Uterine body longitudinal axis, uterine cervix longitudinal axis, and UCA can be associated to PID. This article is protected by copyright. All rights reserved.

Secretory Leukocyte Protease Inhibitor (SLPI) in mucosal tissues: Protects against inflammation, but promotes cancer

The immune system is continuously challenged with large quantities of exogenous antigens at the barriers between the external environment and internal human tissues. Antimicrobial activity is essential at these sites, though the immune responses must be tightly regulated to prevent tissue destruction by inflammation. Secretory Leukocyte Protease Inhibitor (SLPI) is an evolutionarily conserved, pleiotropic protein expressed at mucosal surfaces, mainly by epithelial cells. SLPI inhibits proteases, exerts antimicrobial activity and inhibits nuclear factor-kappa B (NF-κB)-mediated inflammatory gene transcription. SLPI maintains homeostasis at barrier tissues by preventing tissue destruction and regulating the threshold of inflammatory immune responses, while protecting the host from infection. However, excessive expression of SLPI in cancer cells may have detrimental consequences, as recent studies demonstrate that overexpression of SLPI increases the metastatic potential of epithelial tumors. Here, we review the varied functions of SLPI in the respiratory tract, skin, gastrointestinal tract and genitourinary tract, and then discuss the mechanisms by which SLPI may contribute to cancer.

Contribution of Epithelial Cells to Defense Mechanisms in the Human Vagina

PURPOSE OF REVIEW

The vaginal milieu in women differs from that of other mammals, including non-human primates, in composition of secretions, the endogenous microbiota, and level of acidity. These changes apparently reflect evolutionary variations that maximized productive responses to a uniquely human vaginal environment. This review will highlight recent findings on properties of human vaginal epithelial cells that contribute to maintenance of a healthy vaginal environment.

RECENT FINDINGS

Vaginal epithelial cells are responsive to the composition of the vaginal microbiome even in women who are in apparently good health and do not exhibit any adverse physical symptoms. This is especially important during pregnancy when immune defenses are modified and an effective epithelial cell-derived anti-microbial activity is essential to prevent the migration to the uterus of bacteria potentially harmful to pregnancy progression. When Lactobacillus crispatus numerically predominates in the vagina, epithelial cell activity is low. Conversely, predominance of Lactobacillus iners, Gardnerella vaginalis, or other non-Lactobacilli evokes production and release of a large variety of compounds to minimize the potentially negative consequences of an altered microbiome. The extent of autophagy in vaginal epithelial cells, a basic process that functions to maintain intracellular homeostasis and engulf microbial invaders, is also sensitive to the external microbial environment Vaginal epithelial cells bind and release norepinephrine and upregulate their anti-microbial activity in response to external stress. Vaginal epithelial cells in women are responsive to local conditions that are unique to humans and, thereby, contribute to maintenance of a healthy milieu.

Cervicitis: Etiology, diagnosis and treatment

Cervicitis is the inflammation of the cervix. It is usually caused by an infectious agent, usually sexually transmitted. Cervicitis is frequently asymptomatic and silent infection can cause complications of the upper genital tract. The symptoms are usually nonspecific, the most significant being an increase in vaginal discharge and/or intermenstrual bleeding. For its diagnosis, there are commercial systems based on molecular techniques that include almost all of the known pathogens associated with cervicitis, although cultures should not be abandoned due to the need to conduct studies of susceptibility to antibiotics. It is recommended to initiate an empirical antibiotic therapy that covers C.trachomatis and N.gonorrhoeae in the case of women at high risk of infection by these pathogens, especially if the follow-up is not assured or adequate diagnostic tests are not available. In women with low risk of sexually transmitted infection, antibiotic therapy should be adjusted to the results of the microbiological results.

Assessment of microbiota:host interactions at the vaginal mucosa interface

There is increasing appreciation of the role that vaginal microbiota play in health and disease throughout a woman's lifespan. This has been driven partly by molecular techniques that enable detailed identification and characterisation of microbial community structures. However, these methods do not enable assessment of the biochemical and immunological interactions between host and vaginal microbiota involved in pathophysiology. This review examines our current knowledge of the relationships that exist between vaginal microbiota and the host at the level of the vaginal mucosal interface. We also consider methodological approaches to microbiomic, immunologic and metabolic profiling that permit assessment of these interactions. Integration of information derived from these platforms brings the potential for biomarker discovery, disease risk stratification and improved understanding of the mechanisms regulating vaginal microbial community dynamics in health and disease.

HIV-Enhancing and HIV-Inhibiting Properties of Cationic Peptides and Proteins

Cationic antimicrobial peptides and proteins have historically been ascribed roles in innate immunity that infer killing of microbial and viral pathogens and protection of the host. In the context of sexually transmitted HIV-1, we take an unconventional approach that questions this paradigm. It is becoming increasingly apparent that many of the cationic polypeptides present in the human genital or anorectal mucosa, or human semen, are capable of enhancing HIV-1 infection, often in addition to other reported roles as viral inhibitors. We explore how the in vivo environment may select for or against the HIV-enhancing aspects of these cationic polypeptides by focusing on biological relevance. We stress that the distinction between enhancing and inhibiting HIV-1 infection is not mutually exclusive to specific classes of cationic polypeptides. Understanding how virally enhancing peptides and proteins act to promote sexual transmission of HIV-1 would be important for the design of topical microbicides, mucosal vaccines, and other preventative measures.

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.

Distribution and factors associated with salivary secretory leukocyte protease inhibitor concentrations

OBJECTIVES

This cross-sectional study examined the distribution and correlates of salivary secretory leukocyte protease inhibitor (SLPI) concentrations within a multinational cohort of men.

METHODS

Extracellular SLPI was measured in oral gargle cell supernatants of 378 men from three countries using an ELISA-based assay. Risk factor data were collected by a questionnaire. Factors associated with SLPI were assessed using linear and logistic regression for continuous and categorical SLPI, respectively.

RESULTS

Among men aged 18-73 years, the median SLPI concentration was 492.0 ng ml^-1 (range: 2.3-1919.9). In multivariable modeling, men in Brazil and younger men (18-30 years) were more likely to have higher levels of SLPI [adjusted odds ratio (aOR) 3.84; 95% confidence interval (CI): 1.94-7.59, and aOR 3.84; 95% CI: 1.98-7.43, respectively]. Men with a self-reported sexually transmitted diseases diagnosis in the past 6 months were more likely to have higher SLPI levels (aOR 2.98; 95% CI: 1.1-7.83) and men reporting bleeding/swollen gums were less likely to have higher SLPI (aOR 0.34; 95% CI: 0.15-0.79). Similar results were observed for linear regression models.

CONCLUSIONS

Secretory leukocyte protease inhibitor concentrations varied significantly by country and decreased with increasing age. The interaction between SLPI, modifiable factors, and oral infections that influence cancer risk warrants further investigation.

Bacterial vaginosis: a critical analysis of current knowledge

Bacterial vaginosis (BV), the change from a Lactobacillus-dominant vaginal microbiota to an anaerobic and facultative bacterial dominance, is associated with pathological sequelae. In many BV-positive women their microbiota is in fact normal and unrelated to pathology. Whether or not the dominance of BV-associated bacteria persists depends upon interactions between host and bacterial factors. Inconsistencies in diagnosis and erroneous associations with pathology may be due to a failure to differentiate between sub-populations of women. It is only in those women with a BV diagnosis in which the identified bacteria are atypical and persist that BV may be a clinical problem requiring intervention.

TWEETABLE ABSTRACT

Improved diagnosis of bacterial vaginosis is needed to accurately determine its role in pathology.

Elevated concentration of secretory leukocyte protease inhibitor in the cervical mucus before delivery

BACKGROUND

Cervical remodeling during parturition progresses under exquisite regulation by immunologic mediators and proteases. Secretory leukocyte protease inhibitor is a secretory protein that can function as an antimicrobial peptide, an antiinflammatory molecule, and a protease inhibitor. The involvement of secretory leukocyte protease inhibitor in cervical remodeling before and during parturition is understood poorly.

OBJECTIVE

We aimed to reveal the role of secretory leukocyte protease inhibitor in the cervical remodeling process before normal term delivery and to evaluate its utility as a predictive biomarker for timing of delivery.

STUDY DESIGN

Cervical mucus samples were collected prospectively at weekly prenatal visits from a cohort of pregnant women at term. The secretory leukocyte protease inhibitor concentrations in 95 mucus samples that were obtained from 49 women with uncomplicated pregnancy who subsequently underwent normal vaginal delivery were assessed. Alterations in secretory leukocyte protease inhibitor concentrations at term and the association of secretory leukocyte protease inhibitor levels with the time to delivery were analyzed.

RESULTS

A moderate positive correlation with significance was detected between cervical mucus secretory leukocyte protease inhibitor concentrations and days to delivery (r = 0.38; P = .0001). The secretory leukocyte protease inhibitor concentration was significantly higher in samples that were collected within 7 days of delivery when compared with samples that were collected >7 days before delivery (P = .001). Secretory leukocyte protease inhibitor concentrations were also significantly higher in samples from women with premature rupture of membranes when compared with those without premature rupture of membranes (P = .01), all of whom delivered within 7 days. A logistic regression analysis revealed that the cervical secretory leukocyte protease inhibitor level was a significant parameter for the prediction of the onset of delivery. (P = .017; unit odds ratio, 1.28; 95% confidence interval, 1.07-1.61). A cut-off value of cervical secretory leukocyte protease inhibitor/total protein to predict delivery within 7 days was determined to be 1.62 μg/mg (sensitivity, 0.69; specificity, 0.72) using receiver operating characteristic curve-analysis.

CONCLUSION

Secretory leukocyte protease inhibitor concentrations in the cervical mucus elevate progressively before delivery in uncomplicated term pregnancies. Our findings suggest that cervical secretory leukocyte protease inhibitor is a candidate biomarker for delivery prediction.

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.

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.

α-Amylase in Vaginal Fluid: Association With Conditions Favorable to Dominance of Lactobacillus

Vaginal glycogen is degraded by host α-amylase and then converted to lactic acid by Lactobacilli. This maintains the vaginal pH at ≤4.5 and prevents growth of other bacteria. Therefore, host α-amylase activity may promote dominance of Lactobacilli. We evaluated whether the α-amylase level in vaginal fluid is altered in women with bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC) and whether its concentration was associated with levels of lactic acid isomers and host mediators. Vaginal fluid was obtained from 43 women with BV, 50 women with VVC, and 62 women with no vulvovaginal disorders. Vaginal fluid concentrations of α-amylase, secretory leukocyte protease inhibitor (SLPI), hyaluronan, hyaluronidase-1, β-defensin, and elafin were measured by enzyme-linked immunosorbent assay (ELISA). Vaginal concentrations of neutrophil gelatinase-associated lipocalin (NGAL), matrix metalloproteinase (MMP) 8, and d- and l-lactic acid levels in these patients were previously reported. The median vaginal fluid α-amylase level was 1.83 mU/mL in control women, 1.45 mU/mL in women with VVC, and 1.07 mU/mL in women with BV. Vaginal levels of α-amylase were correlated with d-lactic acid (P = .003) but not with l-lactic acid (P > .05) and with SLPI (P < .001), hyaluronidase-1 (P < .001), NGAL (P = .001), and MMP-8 (P = .005). The exfoliation of glycogen-rich epithelial cells into the vaginal lumen by hyaluronidase-1 and MMP-8 may increase glycogen availability and promote α-amylase activity. The subsequent enhanced availability of glycogen breakdown products would favor proliferation of Lactobacilli, the primary producers of d-lactic acid in the vagina. Concomitant production of NGAL and SLPI would retard growth of BV-related bacteria.

Augmentation of Cationic Antimicrobial Peptide Production with Histone Deacetylase Inhibitors as a Novel Epigenetic Therapy for Bacterial Infections

The emergence of antibiotic resistance seriously threatens our ability to treat many common and medically important bacterial infections. Novel therapeutics are needed that can be used alone or in conjunction with antibiotics. Cationic antimicrobial peptides (CAMPs) are important effectors of the host innate defense that exhibit broad-spectrum activity against a wide range of microorganisms. CAMPs are carried within phagocytic granules and are constitutively or inducibly expressed by multiple cell types, including epithelial cells. The role of histone modification enzymes, specifically the histone deacetylases (HDAC), in down-regulating the transcription of CAMP-encoding genes is increasingly appreciated as is the capacity of HDAC inhibitors (HDACi) to block the action of HDACs to increase CAMP expression. The use of synthetic and natural HDACi molecules to increase CAMPs on mucosal surfaces, therefore, has potential therapeutic applications. Here, we review host and pathogen regulation of CAMP expression through the induction of HDACs and assess the therapeutic potential of natural and synthetic HDACi based on evidence from tissue culture systems, animal models, and clinical trials.

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.

Antimicrobial peptides in the female reproductive tract: a critical component of the mucosal immune barrier with physiological and clinical implications

BACKGROUND

At the interface of the external environment and the mucosal surface of the female reproductive tract (FRT) lies a first-line defense against pathogen invasion that includes antimicrobial peptides (AMP). Comprised of a unique class of multifunctional, amphipathic molecules, AMP employ a wide range of functions to limit microbial invasion and replication within host cells as well as independently modulate the immune system, dampen inflammation and maintain tissue homeostasis. The role of AMP in barrier defense at the level of the skin and gut has received much attention as of late. Given the far reaching implications for women's health, maternal and fetal morbidity and mortality, and sexually transmissible and polymicrobial diseases, we herein review the distribution and function of key AMP throughout the female reproductive mucosa and assess their role as an essential immunological barrier to microbial invasion throughout the reproductive cycle of a woman's lifetime.

METHODS

A comprehensive search in PubMed/Medline was conducted related to AMP general structure, function, signaling, expression, distribution and barrier function of AMP in the FRT, hormone regulation of AMP, the microbiome of the FRT, and AMP in relation to implantation, pregnancy, fertility, pelvic inflammatory disease, complications of pregnancy and assisted reproductive technology.

RESULTS

AMP are amphipathic peptides that target microbes for destruction and have been conserved throughout all living organisms. In the FRT, several major classes of AMP are expressed constitutively and others are inducible at the mucosal epithelium and by immune cells. AMP expression is also under the influence of sex hormones, varying throughout the menstrual cycle, and dependent on the vaginal microbiome. AMP can prevent infection with sexually transmissible and opportunistic pathogens of the female reproductive tissues, although emerging understanding of vaginal dysbiosis suggests induction of a unique AMP profile with increased susceptibility to these pathogens. During pregnancy, AMP are key immune effectors of the fetal membranes and placenta and are dysregulated in states of intrauterine infection and other complications of pregnancy.

CONCLUSIONS

At the level of the FRT, AMP serve to inhibit infection by sexually and vertically transmissible as well as by opportunistic bacteria, fungi, viruses, and protozoa and must do so throughout the hormone flux of menses and pregnancy. Guarding the exclusive site of reproduction, AMP modulate the vaginal microbiome of the lower FRT to aid in preventing ascending microbes into the upper FRT. Evolving in parallel with, and in response to, pathogenic insults, AMP are relatively immune to the resistance mechanisms employed by rapidly evolving pathogens and play a key role in barrier function and host defense throughout the FRT.

The Role of Cationic Polypeptides in Modulating HIV-1 Infection of the Cervicovaginal Mucosa

The mucosa and overlying fluid of the female reproductive tract (FRT) are portals for the heterosexual transmission of HIV-1. Toward the ongoing development of topically applied microbicides and mucosal vaccines against HIV-1, it is evermore important to understand how the dynamic FRT mucosa is involved in controlling transmission and infection of HIV-1. Cationic peptides and proteins are the principal innate immune effector molecules of mucosal surfaces, and interact in a combinatorial fashion to modulate HIV-1 infection of the cervix and vagina. While cationic peptides and proteins have historically been categorized as antimicrobial or have other host-benefitting roles, an increasing number of these molecules have been found to augment HIV-1 infection and potentially antagonize host defense. Complex environmental factors such as hormonal fluctuations and/or bacterial and viral co-infections provide additional challenges to both experimentation and interpretation of results. In the context of heterosexual transmission of HIV-1, this review explores how various cationic peptides and proteins participate in modulating host defense against HIV-1 of the cervicovaginal mucosa.

The vaginal microbiota and susceptibility to HIV

There is some evidence that the risk of HIV infection per heterosexual act is higher in low-income countries than in high-income countries. We hypothesize that variations in per sex-act transmission probability of HIV may in part be attributed to differences in the composition and function of the vaginal microbiota between different populations. This paper presents data that are in support of this hypothesis. Experimental and clinical studies have provided evidence that the normal vaginal microbiota plays a protective role against acquisition of HIV and other sexually transmitted infections. Epidemiological studies have convincingly shown that disturbances of the vaginal microbiome, namely intermediate flora and bacterial vaginosis, increase the risk of acquisition of HIV infection. A review of the literature found large differences in prevalence of bacterial vaginosis between different populations, with the highest prevalence rates found in black populations. Possible explanations for these differences are presented including data suggesting that there are ethnic differences in the composition of the normal vaginal microbiota. Lastly, interventions are discussed to restore and maintain a healthy vaginal environment.

Secreted mucosal antimicrobials in the female reproductive tract that are important to consider for HIV prevention

The mucosal microenvironment of the female reproductive tract (FRT) is rich in secreted endogenous antimicrobials that provide the first line of defense against pathogens. This review focuses on the spectrum of secreted antimicrobials found in the FRT that have anti-HIV functions and are regulated by the natural hormonal changes in women's life cycle. Understanding the complex nature of FRT, mucosal microenvironment will enable us to better design therapeutic interventions for women against sexually transmitted pathogens.

Ovarian steroid hormones: effects on immune responses and Chlamydia trachomatis infections of the female genital tract

Female sex hormones are known to regulate the adaptive and innate immune functions of the female reproductive tract. This review aims to update our current knowledge of the effects of the sex hormones estradiol and progesterone in the female reproductive tract on innate immunity, antigen presentation, specific immune responses, antibody secretion, genital tract infections caused by Chlamydia trachomatis, and vaccine-induced immunity.

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.

Clinical evidence for the role of Trichomonas vaginalis in regulation of secretory leukocyte protease inhibitor in the female genital tract

BACKGROUND

Secretory leukocyte protease inhibitor (SLPI) is responsible for regulating inflammatory damage to and innate and adaptive immune responses in the vaginal mucosa. Depressed cervicovaginal SLPI levels have been correlated with both Trichomonas vaginalis infection and poor reproductive health outcomes.

METHODS

We measured levels of SLPI in 215 vaginal specimens collected from adolescent and young adult females aged 14-22 years. Log-transformed SLPI values were compared by analysis of variance or by an unpaired t test before and after adjustment for confounding effects through the propensity score method.

RESULTS

Females receiving hormonal contraceptives and those with an abnormal vaginal pH had lower SLPI levels as compared to their peers. After propensity score adjustment for race, behavioral factors, hormonal use, and other sexually transmitted infections (STIs), SLPI levels were lower in females with a positive T. vaginalis antigen test result, a vaginal pH >4.5, vaginal leukocytosis, and recurrent (vs initial) T. vaginalis infection, with the lowest levels observed in those with the highest T. vaginalis loads.

CONCLUSIONS

The SLPI level was reduced by >50% in a T. vaginalis load-dependent manner. Future research should consider whether identifying and treating females with low levels of T. vaginalis infection (before they become wet mount positive) would prevent the loss of SLPI and impaired vaginal immunity. The SLPI level could be used as a vaginal-health marker to evaluate interventions and vaginal products.

HIV, sexual violence and special populations: adolescence and pregnancy

The risk of male to female transmission of HIV is impacted by baseline inflammation in the female genital tract, semen viral load and seminal plasma's ability to induce specific patterns of cervical cytokine signalling and influx of immune cell populations. Disruption of the epithelial barrier during non-consensual intercourse may trigger further inflammation and initiation of cell-signalling pathways, thus facilitating transmission of HIV and expansion of local infection. Adolescent and pregnant women are at high risk for sexual violence and may exhibit alterations of genital mucosal immunity that promote immune activation, making them uniquely vulnerable to HIV acquisition.

Secretory leukocyte protease inhibitor binds to Neisseria gonorrhoeae outer membrane opacity protein and is bactericidal

PROBLEM

Secretory leukocyte protease inhibitor (SLPI) is an innate immune peptide present on the genitourinary tract mucosa that has antimicrobial activity. In this study, we investigated the interaction of SLPI with Neisseria gonorrhoeae.

METHOD OF STUDY

ELISA and far-Western blots were used to analyze binding of SLPI to gonococci. The binding site for SLPI was identified by tryptic digests and mass spectrometry. Antimicrobial activity of SLPI for gonococci was determined using bactericidal assays. SLPI protein levels in cell supernatants were measured by ELISA, and SLPI mRNA levels were assessed by quantitative RT-PCR.

RESULTS

SLPI bound directly to the gonococcal Opa protein and was bactericidal. Epithelial cells from the reproductive tract constitutively expressed SLPI at different levels. Gonococcal infection of cells did not affect SLPI expression.

CONCLUSION

We conclude that SLPI is bactericidal for gonococci and is expressed by reproductive tract epithelial cells and thus is likely to play a role in the pathogenesis of gonococcal infection.

Altered biomarkers of mucosal immunity and reduced vaginal Lactobacillus concentrations in sexually active female adolescents

BACKGROUND

Genital secretions collected from adult women exhibit in vitro activity against herpes simplex virus (HSV) and Escherichia coli (E. coli), but prior studies have not investigated this endogenous antimicrobial activity or its mediators in adolescent females.

METHODOLOGY/PRINCIPAL FINDINGS

Anti-HSV and anti-E.coli activity were quantified from cervicovaginal lavage (CVL) specimens collected from 20 sexually active adolescent females (15-18 years). Soluble immune mediators that may influence this activity were measured in CVL, and concentrations of Lactobacillus jensenii and crispatus were quantified by PCR from vaginal swabs. Results for adolescents were compared to those obtained from 54 healthy, premenopausal adult women. Relative to specimens collected from adults, CVL collected from adolescent subjects had significantly reduced activity against E. coli and diminished concentrations of protein, IgG, and IgA but significantly increased anti-HSV activity and concentrations of interleukin (IL)-1α, IL-6 and IL-1 receptor antagonist. Vaginal swabs collected from adolescent subjects had comparable concentrations of L. crispatus but significantly reduced concentrations of L. jensenii, relative to adult swabs.

CONCLUSIONS/SIGNIFICANCE

Biomarkers of genital mucosal innate immunity may differ substantially between sexually active adolescents and adult women. These findings warrant further study and may have significant implications for prevention of sexually transmitted infections in adolescent females.

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.

Microbial products alter the expression of membrane-associated mucin and antimicrobial peptides in a three-dimensional human endocervical epithelial cell model

Our understanding of the mechanisms that regulate tissue-specific mucosal defense can be limited by the lack of appropriate human in vitro models. The endocervix lies between the microbe-rich vaginal cavity and the relatively sterile endometrium and is a major portal of entry for Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, human immunodeficiency virus (HIV), and herpes simplex virus (HSV) infection in women. The endocervix is lined with a simple epithelium, and these cells produce mucus, which plays a key role in immune defense and reproduction. Here we describe the development of a human three-dimensional endocervical epithelial cell model generated by rotating wall vessel bioreactor technology. The model is composed of cellular aggregates that recapitulate major structural and barrier properties essential for the function and protection of the endocervix, including junctional complexes, microvilli, innate immune receptors, antimicrobial peptides, and mucins, the major structural component of mucus. Using this model, we also report, for the first time, that the membrane-associated mucin genes MUC1, MUC4, and MUC16 are differentially regulated in these aggregates by different bacterial and viral products. Differential induction of antimicrobial peptides was also observed with these products. Together these data define unique and flexible innate endocervical immune signatures that follow exposure to microbial products and that likely play a critical role in the outcome of pathogen challenge at this site.

SLPI and inflammatory lung disease in females

During the course of certain inflammatory lung diseases, SLPI (secretory leucoprotease inhibitor) plays a number of important roles. As a serine antiprotease it functions to protect the airways from proteolytic damage due to neutrophil and other immune cell-derived serine proteases. With respect to infection it has known antimicrobial and anti-viral properties that are likely to contribute to host defence. Another of its properties is the ability to control inflammation within the lung where it can interfere with the transcriptional induction of pro-inflammatory gene expression induced by NF-κB (nuclear factor κB). Thus, factors that regulate the expression of SLPI in the airways can impact on disease severity and outcome. Gender represents once such idiosyncratic factor. In females with CF (cystic fibrosis), it is now thought that circulating oestrogen contributes, in part, to the observed gender gap whereby females have worse disease and poorer prognosis than males. Conversely, in asthma, sufferers who are females have more frequent exacerbations at times of low-circulating oestrogen. In the present paper, we discuss how SLPI participates in these events and speculate on whether regulatory mechanisms such as post-transcriptional modulation by miRNAs (microRNAs) are important in the control of SLPI expression in inflammatory lung disease.

Innate immunity in the human female reproductive tract: endocrine regulation of endogenous antimicrobial protection against HIV and other sexually transmitted infections

Mucosal surfaces of the female reproductive tract (FRT) contain a spectrum of antimicrobials that provide the first line of defense against viruses, bacteria, and fungi that enter the lower FRT. Once thought to be a sterile compartment, the upper FRT is periodically exposed to pathogens throughout the menstrual cycle. More recently, secretions from the upper FRT have been shown to contribute to downstream protection in the lower FRT. In this review, we examine the antimicrobials in FRT secretions made by immune cells and epithelial cells in the upper and lower FRT that contribute to innate protection. Because each site is hormonally regulated to maintain fertility, this review focuses on the contributions of hormone balance during the menstrual cycle to innate immune protection. As presented in this review, studies from our laboratory and others demonstrate that sex hormones regulate antimicrobials produced by innate immune cells throughout the FRT. The goal of this review is to examine the spectrum of antimicrobials in the FRT and the ways in which they are regulated to provide protection against pathogens that compromise reproductive health and threaten the lives of women.

Performance of swabs, lavage, and diluents to quantify biomarkers of female genital tract soluble mucosal mediators

Background

Measurement of immune mediators and antimicrobial activity in female genital tract secretions may provide biomarkers predictive of risk for HIV-1 acquisition and surrogate markers of microbicide safety. However, optimal methods for sample collection do not exist. This study compared collection methods.

Methods

Secretions were collected from 48 women (24 with bacterial vaginosis [BV]) using vaginal and endocervical Dacron and flocked swabs. Cervicovaginal lavage (CVL) was collected with 10 mL of Normosol-R (n = 20), saline (n = 14), or water (n = 14). The concentration of gluconate in Normosol-R CVL was determined to estimate the dilution factor. Cytokine and antimicrobial mediators were measured by Luminex or ELISA and corrected for protein content. Endogenous anti-HIV-1 and anti-E. coli activity were measured by TZM-bl assay or E. coli growth.

Results

Higher concentrations of protein were recovered by CVL, despite a 10-fold dilution of secretions, as compared to swab eluents. After protein correction, endocervical swabs recovered the highest mediator levels regardless of BV status. Endocervical and vaginal flocked swabs recovered significantly higher levels of anti-HIV-1 and anti-E. coli activity than Dacron swabs (P<0.001). BV had a significant effect on CVL mediator recovery. Normosol-R tended to recover higher levels of most mediators among women with BV, whereas saline or water tended to recover higher levels among women without BV. Saline recovered the highest levels of anti-HIV-1 activity regardless of BV status.

Conclusions

Endocervical swabs and CVL collected with saline provide the best recovery of most mediators and would be the optimal sampling method(s) for clinical trials.

Interventions for prevention and treatment of vulvovaginal candidiasis in women with HIV infection

BACKGROUND

Vulvovaginal candidiasis (VVC) is one of the most common fungal infections that recur frequently in HIV infected women. Symptoms of VVC are pruritis, discomfort, dyspareunia, and dysuria. Vulval infection presents as a morbiliform rash that may extend to the thighs. Vaginal infection is associated with white discharge, and plaques are seen on erythematous vaginal walls.Even though rarely or never resulting in systemic fungal infection or mortality, left untreated these lesions contribute considerably to the morbidity associated with HIV infection. Prevention and treatment of this condition is an essential part of maintaining the quality of life for these individuals.

OBJECTIVES

-To compare the efficacy of various antifungals given vaginally or orally for the treatment and prophylaxis of VVC in HIV-infected women and to evaluate the risks of the same.

SEARCH STRATEGY

The search strategy was comprehensive, iterative and based on that of the HIV/AIDS Cochrane Review Group. The aim was to locate all relevant trials, irrespective of publication status or language. Electronic databases :CENTRAL,Medline, EMBASE, LILACS and CINAHL were searched for randomised controlled trials for the years 1980 to 1st October 2010. WHO ICTRP site and other relevant web sites were also searched for conference abstracts.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of palliative, preventative or curative therapy were considered. Participants were HIV positive women receiving one or more of the following:treatment / prophylaxis for VVC or HAART(Highly Active Antiretroviral Therapy).

DATA COLLECTION AND ANALYSIS

Three authors independently assessed the methodological quality of the trials and extracted data. The quality of the evidence generated was graded using the GRADE PRO approach.

MAIN RESULTS

Our search did not yield any trial investigating treatment of VVC in HIV positive women.Two trials dealing with prophylaxis were eligible for inclusion.One trial (n= 323) favoured the use of weekly Fluconazole as compared to placebo (RR 0.68; 95% CI 0.47 to 0.97).The second trial with three arms of comparison;Clotrimazole,Lactobacillus and Placebo gave no definitive results in preventing an episode of VVC. Clotrimazole against placebo (RR 0.49; 95% CI 0.22 to 1.09), Clotrimazole against lactobacillus (RR 1.11; 95% CI 0.45 to 2.76) and lactobacillus against placebo (RR 0.54 ;95% CI 0.26 to 1.13).

AUTHORS' CONCLUSIONS

Implications for practiceNo trials were found addressing treatment of VVC in HIV positive women.In comparison to placebo,Fluconazole was found to be an effective preventative intervention. However, the potential for resistant Candida organisms to develop might impact the feasibility of implementation.Direction of findings suggests that Clotrimazole and Lactobacillus improved the prophylactic outcomes when compared to placebo.Implications for research There is a need to evaluate drugs and drug regimens for VVC treatment and prophylaxis in HIV positive women through randomised clinical trials. Development of resistance to azoles remains under-studied and more work must be done in this area, so as to determine whether routine prophylaxis for VVC is at all needed or whether adequate ART would be sufficient to prevent recurrent VVC. The viral load in vaginal secretions with or without treatment or prophylaxis has not been studied, this is very relevant to the spread of HIV.

Decidual soluble factors participate in the control of HIV-1 infection at the maternofetal interface

Background

Maternofetal transmission (MFT) of HIV-1 is relatively rare during the first trimester of pregnancy despite the permissivity of placental cells for cell-to-cell HIV-1 infection. Invasive placental cells interact directly with decidual cells of the uterine mucosa during the first months of pregnancy, but the role of the decidua in the control of HIV-1 transmission is unknown.

Results

We found that decidual mononuclear cells naturally produce low levels of IL-10, IL-12, IL-15, TNF-α, IFN-α, IFN-γ and CXCL-12 (SDF-1), and large amounts of CCL-2 (MCP1), CCL-3 (MIP-1α), CCL-4 (MIP-1β), CCL-5 (Rantes), CXCL-10 (IP-10), IL-6 and IL-8. CCL-3 and CCL-4 levels were significantly upregulated by in vitro infection with R5 HIV-1 but not X4. Decidual CD14+ antigen presenting cells were the main CCL-3 and CCL-4 producers among decidual leukocytes. R5 and X4 HIV-1 infection was inhibited by decidual cell culture supernatants in vitro. Using HIV-1 pseudotypes, we found that inhibition of the HIV-1 entry step was inhibited by decidual soluble factors.

Conclusion

Our findings show that decidual innate immunity (soluble factors) is involved in the control of HIV-1 infection at the maternofetal interface. The decidua could thus serve as a mucosal model for identifying correlates of protection against HIV-1 infection.

Chlamydial infection increases gonococcal colonization in a novel murine coinfection model

Genital tract infections caused by Neisseria gonorrhoeae and Chlamydia trachomatis serovars D to K occur at high incidence in many areas of the world. Despite high rates of coinfection with these pathogens, investigations of host-parasite interactions have focused on each pathogen individually. We describe here a coinfection model in which female BALB/c mice were first infected with the mouse Chlamydia species C. muridarum and then inoculated with N. gonorrhoeae following treatment with water-soluble 17β-estradiol to promote long-term gonococcal infection. Viable gonococci and chlamydiae were recovered for an average of 8 to 10 days, and diplococci and chlamydial inclusions were observed in lower genital tract tissue by immunohistochemical staining. Estradiol treatment reduced proinflammatory cytokine and chemokine levels in chlamydia-infected mice; however, coinfected mice had a higher percentage of vaginal neutrophils compared to mice infected with either pathogen alone. We detected no difference in pathogen-specific antibody levels due to coinfection. Interestingly, significantly more gonococci were recovered from coinfected mice compared to mice infected with N. gonorrhoeae alone. We found no evidence that C. muridarum increases gonococcal adherence to, or invasion of, immortalized murine epithelial cells. However, increased vaginal concentrations of inflammatory mediators macrophage inflammatory protein 2 and tumor necrosis factor alpha were detected in C. muridarum-infected mice prior to inoculation with N. gonorrhoeae concurrently with the downregulation of cathelicidin-related antimicrobial peptide and secretory leukocyte peptidase inhibitor genes. We conclude that female mice can be successfully infected with both C. muridarum and N. gonorrhoeae and that chlamydia-induced alterations in host innate responses may enhance gonococcal infection.

Subtle perturbations of genital microflora alter mucosal immunity among low-risk pregnant women

OBJECTIVE

Alteration in the vaginal flora has been associated with adverse pregnancy outcomes. The objective of this study was to examine the impact of changes in individual microflora on genital immunity among low-risk pregnant women in early pregnancy.

DESIGN

Cross-sectional study.

SETTING

Large, tertiary care, academic hospital clinic.

POPULATION

Low-risk women were enrolled prior to 14 weeks' gestation.

METHODS

Women were included if they had no medical or previous obstetrical complications, were non-smokers, had no sexually transmitted infections and no intercourse in the last 48 hours. Consenting women underwent speculum examination for collection of vaginal culture and Dacron swabs for cytokine analysis. Semi-quantitative vaginal cultures were performed in a reference laboratory.

MAIN OUTCOME MEASURES

Concentrations of immune mediators were compared in the presence of various organisms. Concentrations were converted to multiples of the median to standardize the values of each mediator. Regression analyses were performed to control for race.

RESULTS

We enrolled 47 women. The frequencies of genital microorganisms were: H(2)O(2) -producing lactobacilli (70%), Ureaplasma urealyticum (66%), Gardnerella vaginalis (45%), anaerobic non-pigmented Gram-negative rods (ANPGNR, 40%), anaerobic pigmented Gram-negative rods (APGNR, 17%). After adjusting for race and body mass index, interleukin-1β, interferon-γ, tumor necrosis factor-α and granulocyte macrophage-colony stimulating factor were increased in the presence of G. vaginalis, ANPGNR, and APGNR. There was no consistent impact on the other markers of immune activation.

CONCLUSION

The presence of individual species impacts genital immunity among low-risk pregnant women. Perturbations in genital immunity could partially explain heterogeneity in adverse pregnancy outcomes.

Biological roles of host defense peptides: lessons from transgenic animals and bioengineered tissues

Host defense peptides (HDPs) have long been recognized as microbicidal agents, but their roles as modulators of innate and adaptive immunity have only more recently been appreciated. The study of transgenic animal and tissue models has provided platforms to improve our understanding of the immune modulatory functions of HDPs. Here, the characterization of transgenic animals or tissue models that over-express and/or are deficient for specific HDPs is reviewed. We also attempt to reconcile this data with evidence from human studies monitoring HDP expression at constitutive levels and/or in conjunction with inflammation, infection models, or disease states. We have excluded activities ascribed to HDPs derived exclusively from in vitro experiments. An appreciation of the way that HDPs promote innate immunity or influence the adaptive immune response is necessary in order to exploit their therapeutic or adjuvant potential and to open new perspectives in understanding the basis of immunity. The potential applications for HDPs are discussed.

Pelvic inflammatory disease

Pelvic inflammatory disease (PID) is an infection-caused inflammatory continuum from the cervix to the peritoneal cavity. Most importantly, it is associated with fallopian tube inflammation, which can lead to infertility, ectopic pregnancy, and chronic pelvic pain. The microbial etiology is linked to sexually transmitted microorganisms, including Chlamydia trachomatis, Neisseria gonorrheae, Mycoplasma genitalium, and bacterial vaginosis-associated microorganisms, predominantly anaerobes. Pelvic pain and fever are commonly absent in women with confirmed PID. Clinicians should consider milder symptoms such as abnormal vaginal discharge, metrorrhagia, postcoital bleeding, and urinary frequency as potential symptoms associated with the disease, particularly in women at risk of sexually transmitted infection. The diagnosis of PID is based on the findings of lower genital tract inflammation associated with pelvic organ tenderness. The outpatient treatment of mild-to-moderate PID should include tolerated antibiotic regimens with activity against the commonly isolated microorganisms associated with PID and usually consists of an extended spectrum cephalosporin in conjunction with either doxycycline or azithromycin. Clinically severe PID should prompt hospitalization and imaging to rule out a tuboovarian abscess. Parenteral broad-spectrum antibiotic therapy with activity against a polymicrobial flora, particularly gram-negative aerobes and anaerobes, should be implemented. Screening for and treatment of Chlamydia infection can prevent PID.

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.