Bacterial vaginosis-associated microflora isolated from the female genital tract activates HIV-1 expression

Bacterial-Viral Interactions: A Factor That Facilitates Transmission Heterogeneities

The transmission of infectious diseases is characterized by heterogeneities that are shaped by the host, the pathogen, and the environment. Extreme forms of these heterogeneities are called super-spreading events. Transmission heterogeneities are usually identified retrospectively, but their contribution to the dynamics of outbreaks makes the ability to predict them valuable for science, medicine, and public health. Previous studies identified several factors that facilitate super-spreading; one of them is the interaction between bacteria and viruses within a host. The heightened dispersal of bacteria colonizing the nasal cavity during an upper respiratory viral infection, and the increased shedding of HIV-1 from the urogenital tract during a sexually transmitted bacterial infection, are among the most extensively studied examples of transmission heterogeneities that result from bacterial-viral interactions. Interrogating these transmission heterogeneities, and elucidating the underlying cellular and molecular mechanisms, are part of much-needed efforts to guide public health interventions, in areas that range from predicting or controlling the population transmission of respiratory pathogens, to limiting the spread of sexually transmitted infections, and tailoring vaccination initiatives with live attenuated vaccines.

Colonization of the cervicovaginal space with Gardnerella vaginalis leads to local inflammation and cervical remodeling in pregnant mice

The role of the cervicovaginal (CV) microbiome in regulating cervical function during pregnancy is poorly understood. Gardnerella vaginalis (G. vaginalis) is the most common bacteria associated with the diagnosis of bacterial vaginosis (BV). While BV has been associated with preterm birth (PTB), clinical trials targeting BV do not decrease PTB rates. It remains unknown if G. vaginalis is capable of triggering molecular, biomechanical and cellular events that could lead to PTB. The objective of this study was to determine if cervicovaginal colonization with G. vaginalis, in pregnant mice, induced cervical remodeling and modified cervical function. CD-1 timed-pregnant mice received a 5X10⁸ CFU/mL intravaginal inoculation of G. vaginalis or control on embryonic day 12 (E12) and E13. On E15, the mice were sacrificed and cervicovaginal fluid (CVF), amniotic fluid (AF), cervix, uterus, placentas and fetal membranes (FM) were collected. Genomic DNA was isolated from the CVF, placenta, uterus and FM and QPCR was performed to confirm colonization. IL-6 was measured in the CVF and AF and soluble e-cadherin (seCAD) was assessed in the CVF by ELISA. RNA was extracted from the cervices to evaluate IL-10, IL-8, IL-1β, TNF-α, Tff-1, SPINK-5, HAS-1 and LOX expression via QPCR. Mucicarmine and trichrome staining was used to assess cervical mucin and collagen. Biomechanical properties of the cervix were studied using quasi-static tensile load-to-failure biomechanical tests. G. vaginalis successfully colonized the CV space. This colonization induced immune responses (increased IL-6 levels in CVF and AF, increased mRNA expression of cervical cytokines), altered the epithelial barrier (increased seCAD in the CVF), induced cervical remodeling (increased mucin production, altered collagen) and altered cervical biomechanical properties (a decrease in biomechanical modulus and an increase in maximum strain). The ability of G. vaginalis to induce these molecular, immune, cellular and biomechanical changes suggests that this bacterium may play a pathogenic role in premature cervical remodeling leading to PTB.

Bacterial vaginosis, human papilloma virus and herpes viridae do not predict vaginal HIV RNA shedding in women living with HIV in Denmark

BACKGROUND

Bacterial vaginosis (BV) has been found to be associated with HIV acquisition and transmission. This is suggested to be due to higher HIV RNA levels in cervicovaginal fluids in women living with HIV (WLWH) with BV, as bacteria associated with BV may induce viral replication and shedding in the genital tract despite undetectable HIV RNA plasma viral load. We examined the prevalence and diagnostic predictors of BV and HIV-1 RNA vaginal shedding in women living with HIV (WLWH) in Denmark, taking into account the presence of human papillomavirus (HPV) and herpes viridae.

METHODS

WLWH between 18-51 years were recruited from six Departments of Infectious Diseases in Denmark during enrolment in the SHADE cohort; a prospective cohort study of WLWH attending regular outpatient care. BV was diagnosed by microscopy of vaginal swabs and PCR was used for detection of BV-associated bacteria, HPV, herpes viridae, and vaginal HIV viral load.

RESULTS

Median age of the 150 included women was 41 years; ethnicity was predominantly White (35%) or Black (47%). The majority (96%) was on ART and had undetectable (85%) plasma HIV RNA (<40 copies/mL). BV was diagnosed in 32%. Overall, 11% had detectable vaginal HIV RNA. Both before and after adjustment for BV, age, ethnicity, plasma HIV RNA, CD4 cell count, herpes viridae and HPV, we found no significant predictors of HIV RNA vaginal shedding.

CONCLUSION

In well-treated WLWH, BV, herpes viridae or HPV do not predict vaginal HIV RNA shedding. This implies that HIV shedding does not seem to be increased by BV.

Correlates of Bacterial Vaginosis Over Long-Term Follow-Up: Impact of HIV Infection

Correlates of bacterial vaginosis (BV) are poorly understood, especially in HIV infection. In a cohort study, HIV-seropositive and comparison seronegative women were assessed every 6 months during 1994-2015. BV was considered present when three of four Amsel criteria were met. Behavioral characteristics were assessed using structured interviews. Multivariable logistic regression used generalized estimating equation models to determine factors associated with BV. Cumulative incidence of BV over time was assessed using the log-rank test. Among 3,730 women (964 HIV seronegative and 2,766 HIV seropositive) contributing 70,970 visits, BV was diagnosed at 2,586 (14.0%) visits by HIV-seronegative women and 6,224 (11.9%) visits by HIV-seropositive women (p < .0001). The cumulative incidence of BV was 530/964 (55.0%) in HIV-seronegative women and 1,287/2,766 (46.5%) in seropositive women (p < .0001). In adjusted analyses, factors associated with BV were younger age, ethnicity, lower income, less education, recruitment site, recruitment in the 2001-2002 cohort, heavier drinking, current smoking, depression, and sex with a male partner; both hormonal contraception and menopause were negatively associated with BV. Of 533 women with prevalent BV, 228 (42.8%) recurred within a year, while persistent BV was found in 12.8% of participants; neither proportion differed by HIV serostatus. Time trends in the proportion of women with BV at any single visit were not identified. BV is common among women with and at risk for HIV, but HIV infection does not predispose to BV, which is associated instead with behavioral and cultural factors.

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.

The vaginal microbiota over an 8- to 10-year period in a cohort of HIV-infected and HIV-uninfected women

BACKGROUND

We identified predominant vaginal microbiota communities, changes over time, and how this varied by HIV status and other factors in a cohort of 64 women.

METHODS

Bacterial DNA was extracted from reposited cervicovaginal lavage samples collected annually over an 8-10 year period from Chicago Women's Interagency HIV Study participants: 22 HIV-negative, 22 HIV-positive with stable infection, 20 HIV-positive with progressive infection. The vaginal microbiota was defined by pyrosequencing of the V1/V2 region of the 16S rRNA gene. Scheduled visits included Bacterial vaginsosis (BV) screening; clinically detected cases were referred for treatment. Hierarchical clustering identified bacterial community state types (CST). Multinomial mixed effects modeling determined trends over time in CST, by HIV status and other factors.

RESULTS

The median follow-up time was 8.1 years (range 5.5-15.3). Six CSTs were identified. The mean relative abundance (RA) of Lactobacillus spp. by CST (with median number of bacterial taxa) was: CST-1-25.7% (10), CST-2-27.1% (11), CST-3-34.6% (9), CST-4-46.8% (9), CST-5-57.9% (4), CST-6-69.4% (2). The two CSTs representing the highest RA of Lactobacillus and lowest diversity increased with each additional year of follow-up (CST-5, adjusted odds ratio (aOR) = 1.62 [95% CI: 1.34-1.94]; CST-6, aOR = 1.57 [95 CI: 1.31-1.89]), while the two CSTs representing lowest RA of Lactobacillus and higher diversity decreased with each additional year (CST-1, aOR = 0.89 [95% CI: 0.80-1.00]; CST-2, aOR = 0.86 [95% CI: 0.75-0.99]). There was no association between HIV status and CST at baseline or over time. CSTs representing lower RA of Lactobacillus were associated with current cigarette smoking.

CONCLUSIONS

The vaginal microbial community significantly improved over time in this cohort of women with HIV and at high risk for HIV who had regular detection and treatment referral for BV.

The effects of chronic binge alcohol on the genital microenvironment of simian immunodeficiency virus-infected female rhesus macaques

Alcohol abuse is a widespread problem among those at risk for and living with HIV and can impact transmission and disease progression. In this study we sought to use the simian immunodeficiency virus (SIV)-macaque model to evaluate the immunological and virological changes in the genital microenvironment of females exposed to chronic alcohol. Female rhesus macaques were treated with alcohol (n=6) or isocaloric sucrose (n=6) for 3 months and then inoculated with SIVmac251. To assess the effects of chronic alcohol on SIV disease and the genital microenvironment, we quantified plasma and genital SIV levels, measured inflammatory cells in genital fluids, and characterized microbial flora by gram stains over 10 weeks post-SIV infection. Following 3 months of alcohol/sucrose treatment, significant differences were observed in the vaginal microenvironment of alcohol-treated animals as compared to controls. Microbial flora of alcohol-treated animals had decreased levels of lactobacillus morphotypes and increased levels of gram-positive cocci relative to sucrose controls. Alcohol-treated animals were also more likely to have white blood cells in vaginal fluids prior to SIV inoculation, which persisted through viral set point. Similar levels of cell-free SIV were observed in plasma and vaginal fluids of both groups, but alcohol-treated animals had a higher incidence and levels of cell-associated SIV shed in vaginal secretions. Chronic alcohol treatment negatively impacts the genital microenvironment prior to and over the course of SIV infection and may increase the risk of genital virus shedding and transmission.

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.

Accuracy of clinical diagnosis of bacterial vaginosis by human immunodeficiency virus infection status

OBJECTIVE

To assess the accuracy of clinical diagnosis of bacterial vaginosis (BV) by using Amsel criteria, overall and by human immunodeficiency virus (HIV) infection status.

METHODS

Women with HIV, or at risk for HIV, participated in the HIV Epidemiology Research Study, a prospective study conducted in 4 US sites. At enrollment and follow-up visits, scheduled at 6-month intervals for ≤ 5 years, participants received gynecologic examinations, had specimens collected, and underwent standardized interviews. We used McNemar test statistic to evaluate agreement between Amsel criteria and Nugent scoring. Using Nugent scoring as the reference standard, we calculated sensitivity and specificity for Amsel criteria and for 3 other classifications of clinical BV. Our results are based on data collected from 9140 study visits by 862 HIV-infected women and 421 HIV-uninfected women.

RESULTS

Amsel criteria and Nugent scoring did not agree in the classification of BV cases (P < 0.01). Amsel criteria had poor sensitivity (60%; 95% confidence interval, 58%-61%) and specificity (90%; 95% confidence interval, 89%-91%) with wide differences in test properties by study site. We found no differences in diagnosing BV by HIV infection status.

CONCLUSIONS

The under- and overdiagnosing of BV clinically suggests that the accuracy of Amsel criteria for routine screening of asymptomatic women might be lower than previous estimates; that clinicians need more rigorous training to apply subjective Amsel criteria accurately; or that wide heterogeneity in cases might prevent agreement between clinical and laboratory diagnoses, with future research needed to better understand the criteria or morphotypes associated with specific adverse outcomes.

Interaction between endogenous bacterial flora and latent HIV infection

Human commensal bacteria do not normally cause any diseases. However, in certain pathological conditions, they exhibit a number of curious behaviors. In HIV infection, these bacteria exhibit bidirectional relationships: whereas they cause opportunistic infections based on immunological deterioration, they also augment HIV replication, in particular, viral replication from latently infected cells, which is attributable to the effect of butyric acid produced by certain anaerobic bacteria by modifying the state of chromatin. Here, we review recent evidence supporting the contributory role of such endogenous microbes in disrupting HIV latency and its potential link to the clinical progression of AIDS.

Identification and characterisation of vaginal lactobacilli from South African women

Background

Bacterial vaginosis (BV), which is highly prevalent in the African population, is one of the most common vaginal syndromes affecting women in their reproductive age placing them at increased risk for sexually transmitted diseases including infection by human immunodeficiency virus-1. The vaginal microbiota of a healthy woman is often dominated by the species belonging to the genus Lactobacillus namely L. crispatus, L. gasseri, L. jensenii and L. iners, which have been extensively studied in European populations, albeit less so in South African women. In this study, we have therefore identified the vaginal Lactobacillus species in a group of 40 African women from Soweto, a township on the outskirts of Johannesburg, South Africa.

Methods

Identification was done by cultivating the lactobacilli on Rogosa agar, de Man-Rogosa-Sharpe (MRS) and Blood agar plates with 5% horse blood followed by sequencing of the 16S ribosomal DNA. BV was diagnosed on the basis of Nugent scores. Since some of the previous studies have shown that the lack of vaginal hydrogen peroxide (H₂O₂) producing lactobacilli is associated with bacterial vaginosis, the Lactobacillus isolates were also characterised for their production of H₂O₂.

Results

Cultivable Lactobacillus species were identified in 19 out of 21 women without BV, in three out of five women with intermediate microbiota and in eight out of 14 women with BV. We observed that L. crispatus, L. iners, L. jensenii, L. gasseri and L. vaginalis were the predominant species. The presence of L. crispatus was associated with normal vaginal microbiota (P = 0.024). High level of H₂O₂ producing lactobacilli were more often isolated from women with normal microbiota than from the women with BV, although not to a statistically significant degree (P = 0.064).

Conclusion

The vaginal Lactobacillus species isolated from the cohort of South African women are similar to those identified in European populations. In accordance with the other published studies, L. crispatus is related to a normal vaginal microbiota. Hydrogen peroxide production was not significantly associated to the BV status which could be attributed to the limited number of samples or to other antimicrobial factors that might be involved.

Systematic review of randomized trials of treatment of male sexual partners for improved bacteria vaginosis outcomes in women

BACKGROUND

Bacterial vaginosis (BV) affects 10% to 30% of women and recurs in 15% to 30% within 3 months after treatment. BV is not considered an sexually transmitted infection, and treatment of the male sexual partner is not recommended. This recommendation is based on the results of 6 randomized controlled trials (RCTs) of male partner treatment for reducing BV recurrence, which did not find a uniformly beneficial effect. These results are incongruous with epidemiologic and microbiologic data suggesting a sexually transmissible component of BV. In light of this disconnect, the 6 RCTs of male treatment were reviewed to assess validity.

METHODS

Trials are summarized according to Consolidated Standards of Reporting Trials guidelines. Absolute differences and risk ratios with binomially obtained 95% confidence intervals were estimated. Post hoc power analyses determined the probability of rejecting the null hypothesis for observed relative effect sizes and for the smallest relative effect size detectable with ≥ 80% power.

RESULTS

Each of the 6 RCTs had significant flaws: randomization methods were either overtly deficient or insufficiently reported; 5 RCTs used suboptimal treatment regimens in women; adherence to treatment in women was not reported in any trial, and adherence in men was reported in only 2 trials; all 6 trials had limited power. None assessed whether antibiotic treatment affected the penile microbiota.

CONCLUSIONS

Although the RCT is the gold standard for assessing efficacy, biased results can mislead decision making. By current standards, it is unlikely that the results of any of these trials would be considered conclusive. Specific recommendations are made to examine whether BV-associated bacteria may be sexually transferred.

The role of co-infections in mother-to-child transmission of HIV

In HIV-infected women, co-infections that target the placenta, fetal membranes, genital tract, and breast tissue, as well as systemic maternal and infant infections, have been shown to increase the risk for mother-to-child transmission of HIV (MTCT). Active co-infection stimulates the release of cytokines and inflammatory agents that enhance HIV replication locally or systemically and increase tissue permeability, which weakens natural defenses to MTCT. Many maternal or infant co-infections can affect MTCT of HIV, and particular ones, such as genital tract infection with herpes simplex virus, or systemic infections such as hepatitis B, can have substantial epidemiologic impact on MTCT. Screening and treatment for co-infections that can make infants susceptible to MTCT in utero, peripartum, or postpartum can help reduce the incidence of HIV infection among infants and improve the health of mothers and infants worldwide.

Genital tract viral load in HIV Type 1-positive women correlates with specific cytokine levels in cervical-vaginal secretions but is not a determinant of infectious virus or anti-HIV activity

As the AIDS epidemic continues with women being disproportionately affected, it is crucial to understand factors that predict the risk of heterosexual HIV-1 transmission. We investigated whether genital tract viral load (GTVL) in cervical-vaginal lavages (CVL) from HIV-1-positive women with moderately low CD4 T cell counts correlates with cytokine levels, antimicrobial concentrations, and intrinsic anti-HIV activity. CVL were collected from 19 HIV-1-positive women with moderately low CD4 T cell counts [mean 381 cells/mm(3) (227-536 cells/mm(3))]. None of the women was on antiretroviral therapy. The women were categorized into those with detectable GTVL or those with undetectable GTVL (detectable GTVL RNA levels > 400 copies/ml). Women were also categorized according to bacterial vaginosis (BV) status irrespective of GTVL. The TZM-bl assay was used to determine the presence of infectious virus and anti-HIV activity. Significantly higher levels of RANTES, Eotaxin, Fractalkine, IL-1α, IL-6, MCP-1, MIP1β, MIP1α, TNF-α, and GM-CSF were observed in women with detectable GTVL compared to women with undetectable GTVL. No significant differences were observed in the following cytokines and chemokines: G-CSF, IL-1RA, IL-8, and IP-10. GTVL did not correlate either with antimicrobials known to have anti-HIV activity or with the presence of infectious virus. BV status did not have a significant effect on anti-HIV activity. These findings further our understanding of the role of GTVL in determining the cytokine and chemokine milieu in the female reproductive tract.

HIV-1 infection of human intestinal lamina propria CD4+ T cells in vitro is enhanced by exposure to commensal Escherichia coli

Microbial translocation has been linked to systemic immune activation in HIV-1 disease, yet mechanisms by which microbes may contribute to HIV-associated intestinal pathogenesis are poorly understood. Importantly, our understanding of the impact of translocating commensal intestinal bacteria on mucosal-associated T cell responses in the context of ongoing viral replication that occurs early in HIV-1 infection is limited. We previously identified commensal Escherichia coli-reactive Th1 and Th17 cells in normal human intestinal lamina propria (LP). In this article, we established an ex vivo assay to investigate the interactions between Th cell subsets in primary human LP mononuclear cells (LPMCs), commensal E. coli, and CCR5-tropic HIV-1(Bal). Addition of heat-killed E. coli to HIV-1-exposed LPMCs resulted in increases in HIV-1 replication, CD4 T cell activation and infection, and IL-17 and IFN-γ production. Conversely, purified LPS derived from commensal E. coli did not enhance CD4 T cell infection. E. coli exposure induced greater proliferation of LPMC Th17 than Th1 cells. Th17 cells were more permissive to infection than Th1 cells in HIV-1-exposed LPMC cultures, and Th17 cell infection frequencies significantly increased in the presence of E. coli. The E. coli-associated enhancement of infection was dependent on the presence of CD11c(+) LP dendritic cells and, in part, on MHC class II-restricted Ag presentation. These results highlight a potential role for translocating microbes in impacting mucosal HIV-1 pathogenesis during early infection by increasing HIV-1 replication and infection of intestinal Th1 and Th17 cells.

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.

Short-chain fatty acids induce pro-inflammatory cytokine production alone and in combination with toll-like receptor ligands

PROBLEM

Short-chain fatty acids (SCFAs), produced at relatively high levels by anaerobic bacteria in bacterial vaginosis (BV), are believed to be anti-inflammatory. BV, a common alteration in the genital microbiota associated with increased susceptibility to HIV infection, is characterized by increased levels of both pro-inflammatory cytokines and SCFAs. We investigated how SCFAs alone or together with Toll-like receptor (TLR) ligands affected pro-inflammatory cytokine secretion.

METHOD OF STUDY

Cytokines were measured by ELISA. Flow was used for phenotyping and reactive oxygen species (ROS) measurement.

RESULTS

Short-chain fatty acids, at 20 mM, induced interleukin (IL)-8, IL-6, and IL-1β release, while lower levels (0.02-2 mM) did not induce cytokine secretion. Levels >20 mM were toxic to cells. Interestingly, lower levels of SCFAs significantly enhanced TLR2 ligand- and TLR7 ligand-induced production of IL-8 and TNFα in a time- and dose-dependent manner, but had little effect on lipopolysaccharide-induced cytokine release. SCFAs mediated their effects on pro-inflammatory cytokine production at least in part by inducing the generation of ROS.

CONCLUSION

Our data suggest that SCFAs, especially when combined with specific TLR ligands, contribute to a pro-inflammatory milieu in the lower genital tract and help further our understanding of how BV affects susceptibility to microbial infections.

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.

The aetiology of bacterial vaginosis

Bacterial vaginosis (BV) is the most common vaginal infection among women of childbearing age. This condition is notorious for causing severe complications related to the reproductive health of women. Five decades of intense research established many risk factors for acquisition of BV; however, because of the complexity of BV and lack of a reliable animal model for this condition, its exact aetiology remains elusive. In this manuscript, we use a historical perspective to critically review the development of major theories on the aetiology of BV, ultimately implicating BV-related pathogens, healthy vaginal microbiota, bacteriophages and the immune response of the host. None of these theories on their own can reliably explain the epidemiological data. Instead, BV is caused by a complex interaction of multiple factors, which include the numerous components of the vaginal microbial ecosystem and their human host. Many of these factors are yet to be characterized because a clear understanding of their relative contribution to the aetiology of BV is pivotal to the formulation of an effective treatment for and prophylaxis of this condition.

Correlates of HIV-1 genital shedding in Tanzanian women

Background

Understanding the correlates of HIV shedding is important to inform strategies to reduce HIV infectiousness. We examined correlates of genital HIV-1 RNA in women who were seropositive for both herpes simplex virus (HSV)-2 and HIV-1 and who were enrolled in a randomised controlled trial of HSV suppressive therapy (aciclovir 400 mg b.i.d vs. placebo) in Tanzania.

Methodology

Samples, including a cervico-vaginal lavage, were collected and tested for genital HIV-1 and HSV and reproductive tract infections (RTIs) at randomisation and 6, 12 and 24 months follow-up. Data from all women at randomisation and women in the placebo arm during follow-up were analysed using generalised estimating equations to determine the correlates of cervico-vaginal HIV-1 RNA detection and load.

Principal Findings

Cervico-vaginal HIV-1 RNA was detected at 52.0% of 971 visits among 482 women, and was independently associated with plasma viral load, presence of genital ulcers, pregnancy, bloody cervical or vaginal discharge, abnormal vaginal discharge, cervical ectopy, Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, an intermediate bacterial vaginosis score and HSV DNA detection. Similar factors were associated with genital HIV-1 RNA load.

Conclusions

RTIs were associated with increased presence and quantity of genital HIV-1 RNA in this population. These results highlight the importance of integrating effective RTI treatment into HIV care services.

Bacterial vaginosis in HIV-infected women induces reversible alterations in the cervical immune environment

BACKGROUND

Bacterial vaginosis (BV) has been associated with increased HIV cervicovaginal shedding. We hypothesized that this might relate to BV-associated increases in mucosal activated CD4 T cells, which could enhance local HIV replication.

METHODS

Vaginal flora, cytokine/chemokine levels, and mucosal immune cell populations collected by cervical cytobrush were analyzed in 15 HIV-infected Kenyan female sex workers, before and after BV therapy with oral metronidazole.

RESULTS

Therapy reduced the Nugent score in all but 1 participant, and BV elimination was associated with reduced genital levels of interleukin 1beta(IL1beta), interleukin 8 (IL-8), and Regulated Upon Activation Normal T-cell Expressed and Secreted (RANTES). In addition, BV elimination reduced the total number of cervical CD4 T cells, including those expressing the HIV coreceptor CCR5 and the activation marker CD69.

CONCLUSIONS

BV induces significant and reversible alterations in cervical immune cell populations and local inflammatory cytokines that would be expected to enhance local HIV replication.

Mutations generated in human immunodeficiency virus type 1 long terminal repeat during vertical transmission correlate with viral gene expression

We determined the effect of mutations generated in HIV-1 LTR on viral gene expression in six mother-infant pairs following vertical transmission. We show that the functional domains critical for LTR function, the promoter (TATAA), enhancers (three SpI and two NFkappaB sites), the modulatory region (two AP-I sites, two NFAT, one NF-IL6 site, one Ets-1, and one USF-1) and the TAR region were generally conserved among mother-infant pairs, although we observed several patient and pair specific mutations in these important domains. We then determined the promoter activity of our mother-infant LTR sequences by measuring CAT gene expression, which was driven by these LTRs and found that most of these HIV-1 LTRs derived from 6 mother-infant pairs were functional. However, mutations in the important transcription factor binding sites, including TATAA, SpI, NFkappaB, AP-I, NFAT, NF-IL6, Ets-1, USF-1 and TAR resulted in reduced LTR driven CAT gene expression. Taken together, conservation of functional domains in the LTR during vertical transmission supports the notion that a functional LTR is critical in viral replication and pathogenesis and mutations generated during the course of infection correlated with HIV-1 gene expression.

Genital tract interleukin-8 but not interleukin-1beta or interleukin-6 concentration is associated with bacterial vaginosis and its clearance in HIV-infected and HIV-uninfected women

Genital tract infections and cytokine perturbations are associated with increased HIV acquisition and transmission. We measured the relationship between bacterial vaginosis (BV) and concentrations of Interleukin-8 (IL-8), Interleukin-1β (IL-1β), and Interleukin-6 (IL-6) in cervicovaginal lavage (CVL) specimens collected longitudinally from 16 HIV-infected and 8 HIV-uninfected high-risk women. CVL samples were analyzed when women presented with BV, and at their next visit, after successful treatment, when BV was cleared. A subset of participants had cytokine levels evaluated at three consecutive clinic visits: before developing BV, at the time of BV diagnosis, and after clearing BV. Significantly higher IL-8, but not IL-1β or IL-6 levels were present when women had active BV compared to when BV was absent. Trends in cytokine levels were similar for HIV-infected and HIV-uninfected women. BV in these women was associated with significantly higher concentrations of genital tract IL-8 which decreased 2.4 fold when BV was cleared.

Bacterial vaginosis and human immunodeficiency virus infection

Epidemiologic studies indicate that bacterial vaginosis (BV), a common alteration of lower genital tract flora in women, is associated with increased susceptibility to HIV infection. Other recent studies show that HIV is detected more frequently and at higher levels in the lower genital tract of HIV-seropositive women with BV. In vitro studies show that genital tract secretions from women with BV or flora associated with BV induce HIV expression in infected cells. The increased HIV expression appears to be due at least in part to activation through Toll-like receptors (TLR), specifically TLR2. Further research is needed to elucidate how BV contributes to HIV acquisition and transmission.

TLR2-mediated cell stimulation in bacterial vaginosis

Bacterial vaginosis (BV) is associated with preterm labor, pelvic inflammatory disease (PID) and increased HIV acquisition, although the pathways that mediate these pathological effects have not been elucidated. To determine the presence of Toll-like receptor (TLR)-ligands and their specificity in BV, genital tract fluids were collected from women with and without BV by cervicovaginal lavage (CVL). The CVL samples were evaluated for their ability to stimulate secretion of proinflammatory cytokines and to activate NFkappaB and the HIV long terminal repeat (LTR), indicators of TLR activation, in human monocytic cells. Stimulation with BV CVLs induced higher levels of IL-8 and TNFalpha secretion, as well as higher levels of HIV LTR and NFkappaB activation, than CVLs from women with normal healthy bacterial flora. To identify which TLRs were important in BV, 293 cells expressing specific TLRs were exposed to CVL samples. BV CVLs induced higher IL-8 secretion by cells expressing TLR2 than CVLs from women without BV. Surprisingly, BV CVLs did not stimulate cells expressing TLR4/MD2, although these cells responded to purified lipopolysaccharide (LPS), a TLR4 ligand. BV CVLs, in cells expressing TLR2, also activated the HIV LTR. Thus, these studies show that soluble factor(s) present in the lower genital tract of women with BV activate cells via TLR2, identifying a pathway through which BV may mediate adverse effects.

The Occurrence of Vaginal Infections Among HIV-Infected and High-Risk HIV-Uninfected Women

OBJECTIVES

To evaluate changes over time in rates of bacterial vaginosis (BV), trichomoniasis (TV), and yeast vaginitis (YV) among HIV-infected and similar HIV-uninfected women.

METHODS

Two thousand fifty-six HIV-infected women and 554 HIV-uninfected women were evaluated semiannually from 1994 until March 2003 in a prospective cohort study. BV was diagnosed by Gram stain, TV by wet mount, and YV by symptoms with microscopically visible hyphae or positive culture. Trends were assessed using Poisson models.

RESULTS

At baseline, BV was present in 42.8% and 47.0% of HIV-infected and uninfected women (P = 0.21), TV in 6.1% and 7.8% (P = 0.17), and YV in 10.0% and 3.8% (P < 0.001). Over time, rates of BV and TV decreased significantly in both groups, whereas rates of YV declined only among HIV-infected women. Risk of BV was not associated with HIV status, whereas HIV-infected women had a lower risk of TV. Highly active antiretroviral therapy (HAART) use was associated with decreased risk of all 3 infections.

CONCLUSIONS

: Declines in BV, TV, and YV represent decreased morbidity for HIV-infected women and, potentially, decreased risk of transmission of HIV, because each has been associated with increased genital detection of HIV.

Mode of action of lactocin 160, a bacteriocin from vaginal Lactobacillus rhamnosus

OBJECTIVES: To determine the mechanism of antimicrobial action of lactocin 160, a bacteriocin produced by the healthy vaginal strain of Lactobacillus rhamnosus, using an established model, with Micrococcus luteus ATCC 10420 as a test organism. METHODS: Sensitivity of M. luteus to lactocin 160 was determined by the diffusion assay. Loss of cellular ATP in the lactocin-treated cells was elucidated using a commercially available ATP determination kit (luciferin-luciferase bioluminescence assay). Luminescence intensity as a reflection of ATP quantity was determined using a luminometer. Dissipation of membrane potential (Deltapsi) was studied using fluorophore DiSC3(5) with the fluorescence spectrum sensitive to changes in Deltapsi. RESULTS: Lactocin 160 inhibited growth of M. luteus ATCC 10420 at a concentration of 5 microg/ml. There were no significant changes in the intracellular ATP level of M. luteus upon the addition of 20 microg/ml of lactocin 160. However, the extracellular ATP level increased significantly. This means that the treatment of cells with lactocin 160 resulted in an efflux of ATP from inside the cells. Therefore, a partially purified lactocin 160 preparation (16 microg /ml of the bacteriocin in the sample) killed sensitive cells and dissipated 3.12 +/- 0.36% of Deltapsi. CONCLUSION: Lactocin 160 has a mode of action typical for bacteriocins. It disturbs the cellular membrane (Deltapsi dissipation) and induces ATP efflux, most likely because of the pore formation, which is a common mechanism of action for many bacteriocins.

Molecular methodology in determining vaginal flora in health and disease: Its time has come

The microbial flora of the human vagina can affect the health of women, their fetuses, and newborns. Conventional cultivation methods fail to detect some fastidious vaginal bacteria, leading to an incomplete census. Recent advances in molecular biology have facilitated the detection and identification of bacteria without cultivation, and the advantages and limitations of this approach are described. Molecular studies of the vaginal flora have discovered many uncultivated bacterial species. For instance, several novel bacteria in the Clostridiales order are highly specific indicators of bacterial vaginosis, and bacteria related to Megasphaera, Leptotrichia, Atopobium, and Dialister species are commonly found in subjects with bacterial vaginosis. A more complete understanding of vaginal microbial populations resulting from the adoption of molecular tools may lead to better strategies to maintain healthy vaginal floras and will create opportunities to explore the role of novel bacteria in reproductive tract diseases.

Relationship of U1 cell HIV-stimulatory activity to bacterial vaginosis and HIV genital tract virus load

Bacterial vaginosis (BV) has been associated with HIV sexual transmission and increased levels of genital tract HIV RNA. We postulated that BV induces the appearance of substances in the genital tract that stimulate HIV expression locally. To test this, we measured HIV RNA levels in genital mucosal fluid from women with or without BV (defined by Nugent score) and compared them with the ability of those fluids to stimulate HIV expression in the chronically HIV-infected monocytic line U1. The U1 activity was significantly higher in women with BV (median = 1320 pg/ml p24) than in women with normal flora (median = 103 pg/ml p24, p = 0.0001). However, levels of the U1 activity were not significantly associated with levels in the genital tract of HIV RNA. Levels of the U1 activity were also not associated with levels of Gardnerella vaginalis or Mycoplasma hominis in genital fluids, suggesting these bacteria were not the source of the activity. Thus, while these data show a strong association of U1 stimulatory activity with BV, no influence of the U1 activity on genital tract HIV expression was observed.

HIV-Inducing Factor in Cervicovaginal Secretions Is Associated With Bacterial Vaginosis in HIV-1-Infected Women

OBJECTIVE

Certain cervicovaginal lavage (CVL) fluid samples obtained from HIV-1-infected and uninfected women stimulate in vitro HIV-1 replication. This activity, HIV-inducing factor (HIF), changes when CVL fluid is heated. We sought to confirm a previous observation that HIF was associated with bacterial vaginosis (BV).

METHODS

HIF was measured in unheated and heated CVL fluid obtained from HIV-1-infected women and compared with the presence of BV by Nugent scores, other genital tract conditions, and cervicovaginal HIV-1 shedding.

RESULTS

Among the 295 women studied, 54% of CVL samples had HIF activity and 21% showed heat-stable HIF activity. In adjusted logistic regression, heat-stable HIF was associated with BV (odds ratio [OR]=51.7, 95% confidence interval [CI]: 5.0, 530.7) and with intermediate flora (OR=43.3, 95% CI: 3.6, 521.1); heat-labile HIF was not associated with BV. Neither heat-stable nor heat-labile HIF was associated with other cervicovaginal conditions nor, after controlling for plasma viral load, with genital tract HIV-1 shedding.

CONCLUSION

We confirmed the association of HIF with BV and attribute it to the heat-stable component. Heat-stable activity is also associated, although less strongly, with intermediate vaginal flora. We propose that heat-stable HIF is a result of products of BV-associated bacteria.

Evolving issues in understanding and treating bacterial vaginosis

Bacterial vaginosis is a synergistic polymicrobial syndrome characterized by depletion of Lactobacillus spp., especially those that produce hydrogen peroxide, and an intense increase in the quantity of commensal vaginal anaerobic bacteria to 100- to 1000-fold above normal levels. While the bacterial spectrum of these organisms has long been known to include Gardnerella vaginalis, Prevotella spp., anaerobic Gram-positive cocci, Mobiluncus spp. and Mycoplasma hominis, innovative use of molecular diagnostics has identified novel species apparently associated with this syndrome, including Atopobium vaginalis. Effecting resolution of bacterial vaginosis is important, in particular for the 8 to 23% of women afflicted with symptomatic disease during their reproductive years. Bacterial vaginosis has been consistently associated with numerous adverse sequelae related to the upper genital tract, including pelvic inflammatory disease and postsurgical infection in the setting of invasive gynecologic procedures, and may increase women's risk of acquiring HIV infection. Pregnant women with bacterial vaginosis experience a higher rate of preterm delivery and low-birth-weight infants. While antibiotics with activity against anaerobes--typically, metronidazole and clindamycin applied vaginally or taken orally--are the mainstays of therapy, bacterial vaginosis frequently recurs. For these reasons, innovative approaches to therapy are urgently required.

Antigenic complementarity among AIDS-associated infectious agents and molecular mimicry of lymphocyte proteins as inducers of lymphocytotoxic antibodies and circulating immune complexes

BACKGROUND

People at risk for acquired immunodeficiency syndrome (AIDS) have high rates of cofactor infections in addition to HIV, including cytomegalovirus, hepatitis viruses, Mycobacteria, Mycoplasmas, and Staphylococcus aureus. Most people with AIDS also develop lymphocytotoxic antibodies (LCTA) and circulating immune complexes (CIC). While HIV proteins mimic HLA antigens, many cofactor agents mimic CD4 antigens. It has therefore been proposed that cofactor infections may interact with HIV by producing complementary antigens that induce LCTA and CIC, and that the resulting immunological dysfunction is part of AIDS pathogenesis.

OBJECTIVES

To test (1) whether HIV and its cofactor infections elicit complementary (idiotype-anti-idiotype) antibodies, and (2) if any of these antibodies mimic anti-lymphocyte antibodies.

STUDY DESIGN

Two immunological methods are employed to test for antibody complementarity: (1) double antibody diffusion, a modification of Ouchterlony immunodiffusion, in which antibodies are tested for their ability to precipitate each other; (2) double-antibody ELISA, in which an antibody against one infectious agent is adsorbed to an ELISA plate and an antibody against a second agent is used to detect the first.

RESULTS

Data on over a thousand double antibody diffusion (DAD) and about 70 DA-ELISA experiments are reported. These show that only specific pairs of antibodies are complementary: HIV-CMV; HIV-HBV; HIV-tuberculosis; HIV-mycoplasmas; HIV-S. aureus; and CMV-mycoplasmas. In addition, HIV antibodies precipitate CD4 antibodies; CMV antibodies precipitate HLA-DR antibodies; while mycobacteria and mycoplasma antibodies precipitate macrophage antibodies.

CONCLUSIONS

Antibodies elicited by HIV infection can interact with antibodies elicited by cofactor infections to form CIC, and some of these antibodies mimic lymphocyte antibodies so that they may function as LCTA. Since LCTA and CIC are associated with increased lymphocyte death in AIDS, the immune response against cofactors in HIV may play a significant role in AIDS pathogenesis. The fact that both HIV and cofactors elicit antibodies with LCTA characteristics may pose problems for vaccine development.

[Factors of risk of bacterial vaginosis]

OBJECTIVES

To recognise factors in the host that might condition the appearance of the bacterial vaginosis (BV) syndrome, whether gynae-obstetrical factors, habits of sexual conduct, hygiene, or other factors.

DESIGN

Cross-sectional, observational study.

SETTING

The study was conducted from January 2002 to June 2003 in the Primary Care Dr. Jose Castro Villagrana Community Health Centre at Tlalpan, Mexico City.

PARTICIPANTS

968 patients with an active sexual life who had not taken antibiotics for at least 15 days before the study and who were not menstruating at the moment of taking a swab, 859 of whom had a diagnosis of cervico-vaginitis and 109 had no symptoms.

MAIN MEASUREMENTS

Confidential questionnaire and a cervical-vaginal culture. The Amsel criteria were used to make the diagnosis of bacterial vaginosis.

RESULTS

There was 32.9% prevalence of BV. There was a statistically significant association with factors such as age, start of active sexual life, the number of sexual relations per week, the number of sexual partners, and pregnancy.

CONCLUSIONS

Bacterial vaginosis is the main cause of infectious processes in the vagina. Its appearance appears to be linked to factors involving sexual transmission. Interventions to reduce its prevalence and complications are recommended.

Human immunodeficiency virus (HIV)-specific antibody in cervicovaginal lavage specimens obtained from women infected with HIV type 1

To evaluate correlates of anti-human immunodeficiency virus (HIV) type 1 (HIV-1) immunoglobulin (Ig) in the genital tract, anti-HIV-gp120 IgA and IgG titers in cervicovaginal lavage specimens obtained from 104 HIV-1-infected women were measured by enzyme-linked immunosorbent assay. Overall, 24% and 94% of women had detectable anti-gp120 IgA and IgG, respectively. CD4 cell count correlated negatively with total IgA concentration (r=-0.301; P=.0027) and positively with specific IgA activity (anti-gp120 IgA titer/total IgA concentration, r=0.306; P=.0023). Women with bacterial vaginosis had 5-fold lower anti-gp120 IgG titer (P=.0042), 5-fold lower total IgG concentration (P< or =.0001), and 4-fold higher specific IgG activity (P=.0474) compared with women who did not have bacterial vaginosis. Enhanced understanding of correlates of mucosal immunity to HIV-1 may assist in the design of vaccine strategies or in the prevention of vertical transmission of HIV-1.

A systematic review of the epidemiologic interactions between classic sexually transmitted diseases and HIV: how much really is known?

BACKGROUND

Many studies have explored the role of "classic" sexually transmitted diseases (STDs) in determining the pattern of HIV epidemics. However, the many different STDs may contribute in different ways, at different magnitudes.

GOAL

To review available studies on the bidirectional interactions of HIV and STDs to explore the extent of current knowledge on the different influences of the varied STDs in heterosexual HIV epidemics.

METHODS

Longitudinal studies on susceptibility and controlled studies on infectiousness and duration of disease identified on electronic databases through reference lists and citation indices up to the end of 1999 were systematically reviewed, including meta-analyses assessing the influence of STDs on susceptibility to HIV.

RESULTS

Studies have a clear publication bias with a significant result that hinders robust interpretation. However, genital ulcerative disease appears to have a greater impact than nonulcerative disease, and men are more affected than women by the effects of STDs on susceptibility to HIV. There is evidence that STDs increase the infectiousness of HIV from men to women, whereas the evidence is more equivocal for the infectiousness of women. Few studies identify the impact of different STDs, and there is a marked lack of studies investigating the impact of HIV infection on the transmission of other STDs.

CONCLUSIONS

A large body of work has measured the association between STDs and HIV. However, publication bias and gaps in the focus of studies mean that a detailed, quantitative understanding of the interaction requires much more attention.

Factors linked to bacterial vaginosis in nonpregnant women

OBJECTIVES

The purposes of this study were to test the hypothesis that vaginal douching is linked to bacterial vaginosis in both symptomatic and asymptomatic women and to identify other demographic, reproductive, and lifestyle factors associated with bacterial vaginosis.

METHODS

In this cross-sectional study involving 3 clinic sites, 496 nonpregnant women completed a self-administered questionnaire. Their vaginal smears were assessed and cross-validated for bacterial vaginosis.

RESULTS

The prevalence of bacterial vaginosis across clinics ranged from 15% to 30%. In analyses restricted to site 1, adjusted odds ratios (ORs) for bacterial vaginosis remained significant for African American women with 13 or fewer years of education (OR = 5.5, 95% confidence interval [CI] = 2.1, 14.5), hormone use within the past 6 months (OR = 0.5, 95% CI = 0.2, 0.8), and vaginal douching within the past 2 months (OR = 2.9, 95% CI = 1.5, 5.6).

CONCLUSIONS

Two lifestyle factors emerge as strongly associated with bacterial vaginosis: systemic contraceptives appear protective, whereas douching is linked to an increase in prevalence. The temporal relationship between douching and bacterial vaginosis needs further clarification.

Association between bacterial vaginosis and expression of human immunodeficiency virus type 1 RNA in the female genital tract

We assessed the effect of lower genital tract infections on human immunodeficiency virus type 1 (HIV-1) RNA shedding in the female genital tract. Bacterial vaginosis was significantly associated with HIV-1 RNA expression in the female genital tract of HIV-infected women.

Binding of heme by Gardnerella vaginalis

It has been previously demonstrated that Gardnerella vaginalis could acquire iron from a number of different iron-containing compounds, including heme. In this study, the direct binding of heme by G. vaginalis strains was demonstrated utilizing a liquid broth heme-binding assay. Competition studies demonstrated that pretreatment of G. vaginalis cells with other iron sources such as hemoglobin, catalase, and lactoferrin did not affect heme binding. Also, heme binding was not inhibited by preincubation of G. vaginalis cells with protoporphyrin IX. Two potential heme-binding proteins with estimated molecular weights of 30 and 70 kDa were isolated using heme-agarose batch affinity chromatography.

A menstrual cycle pattern for cytokine levels exists in HIV-positive women: implication for HIV vaginal and plasma shedding

OBJECTIVES

To evaluate the effect of the menstrual cycle in HIV-positive women on plasma and genital cytokine levels, interrelationships between vaginal and plasma cytokines, CD4 and CD8 T cell fluctuations, and genital and plasma viral loads.

METHODS

Plasma and cervicovaginal lavage specimens were collected from 55 HIV-positive women with CD4 cell counts < 350 cells/microl during phases of the menstrual cycle. Samples were assayed for IL-1beta, IL-6, IL-4, IL-8, IL-10, TGFbeta, TNFalpha, INFgamma, MIP1alpha, MIP1beta, RANTES, and TNFR-II using enzyme-linked immunosorbent assays. CD4 and CD8 T cell expression was evaluated by flow cytometry. Repeated measures regression models were used to assess the effect of the menstrual cycle on cytokines and viral load. Multivariate repeated regression models were used to assess the correlation among selected cytokines and between selected cytokines and HIV viral load.

RESULTS

Vaginal IL-1beta, IL-4, IL-6, IL-8, IL-10, MIP1beta, RANTES, TGFbeta, and TNFR-II were significantly elevated during menses but were not altered during other phases. Plasma cytokine levels were not altered during the menstrual cycle. A positive Candida culture increased vaginal IL-8 during menses, whereas vaginal discharge was associated with a reduction in vaginal IL-4, IL-10, and RANTES. CD4 and CD8 cell numbers did not vary with the menstrual cycle. Vaginal cytokine levels correlated only with vaginal viral load, in a sampling method-dependent manner.

CONCLUSION

We provide evidence of elevated vaginal cytokine levels during menses, which appear to regulate vaginal and not plasma HIV shedding, suggesting that a menstrual cycle pattern exists for cytokine production in HIV-positive women impacting vaginal shedding of HIV.

Reasons for increased postnatal length of stay & women's perceptions of length of stay

A quality improvement project was conducted by a major maternity provider (3000 births per year) in the western suburbs of Melbourne. The first part of the project explored the reasons for increased length of stay (LOS), beyond the average timeframe for women receiving postnatal care. The perceptions of 100 women on their length of stay was also measured in the second part of the project. Two information audits were conducted to explore reasons for increased LOS. These reasons were varied, and by the time of the second audit, there was a demonstrated reduction in LOS. A Length of Stay Questionnaire was used to investigate women's perceptions of their LOS on discharge from hospital, and by telephone follow-up 14 days post-discharge. Perceptions varied between women and related to issues such as individual health complications, models of care, postnatal education, and degree of support at home. This project has implications for postnatal midwifery care in relation to discharge planning and women's expectations of care following birth.

Microecology, bacterial vaginosis and probiotics: perspectives for bacteriotherapy

Probiotics enriched in lactobacilli have been proposed as an effective and alternative tool to antibiotics for the treatment of bacterial vaginosis. The protective role of H(2)O(2)-producing lactobacilli has been strongly emphasized, but no clear-cut correlation appears to link the metabolic characteristics of administered lactobacilli with the clinical impact of probiotic therapy. On account of our review of basic mechanisms involved in bacterial vaginosis, we suggest that lactobacilli with an elevated arginine deiminase activity could have a greater therapeutic potential than strains producing only H(2)O(2). Preliminary results from our laboratory have demonstrated that treatment with probiotics containing arginine deiminase-positive lactobacilli improves clinical symptoms and is paralleled by a significant decline of polyamine levels in vaginal microenvironment. This is of outstanding interest due to the central role of polyamines in the pathogenesis of bacterial vaginosis. We should critically rethink, against this perspective, the use of probiotics for the treatment of affected women.

Gynecologic infections in human immunodeficiency virus-infected women

The maturation of the acquired immunodeficiency syndrome epidemic has now claimed more than 12 million women worldwide, the majority in undeveloped countries where human immunodeficiency virus (HIV) and sexually transmitted infections coexist and interact synergistically. Among HIV-infected women, there is excessive morbidity due to sexually transmitted diseases (STDs) and gynecologic disorders. This review summarizes the expanding understanding of vaginal flora, vaginitis, cervicitis, pelvic inflammatory disease, and genital ulcer disease in HIV-infected women. In addition to the altered clinical course, complications, and management difficulties of STDs, some gynecologic infections may influence HIV transmission as well as the vertical transmission of HIV to the newborn. Finally, severe immunodeficiency allows unusual opportunistic pathogens to invade the upper and lower genital tract. Control and prevention of gynecologic infections in HIV-positive and HIV-negative women are key components to preventing further HIV transmission.

Binding of catalase by Gardnerella vaginalis

Previous work has demonstrated that Gardnerella vaginalis can utilize catalase as a sole source of iron. In this study, the interaction between G. vaginalis cells and catalase was investigated. G. vaginalis cells were shown to bind digoxigenin (DIG)-labeled catalase using a solid phase dot blot assay. An increase in catalase binding was observed from cells grown under iron-restrictive conditions. Western blot analysis of G. vaginalis proteins resulted in the detection of a putative catalase-binding protein with an estimated molecular mass of 128 kDa. The 128-kDa catalase-binding protein was not detected from intact G. vaginalis cells treated with trypsin prior to Western blot analysis suggesting this protein may be surface-exposed.

Diversity of the HIV-1 long terminal repeat following mother-to-child transmission

A study of the human immunodeficiency virus Type 1 (HIV-1) 5' long terminal repeat (LTR) was performed to determine the extent of variation found within the LTR from 19 mother-infant pairs in Tanzania and to assess whether the LTR is useful in distinguishing maternal sequences that were transmitted to infants. HIV-1 subtypes A, C, and D as well as intersubtype recombinant LTR sequences were detected in mothers and infants. The LTR subtype was 100% concordant between mothers and their infants. Diversity calculations showed a significant reduction in LTR variation in infants compared to their mothers. However, the overall magnitude of LTR variation was less than that found in the env gene from the same individuals. These data suggest a selective constraint active upon the 5' long terminal repeat that is distinct from immune selective pressure(s) directed against HIV-1 structural genes. Detection of maternal LTR variants that were transmitted to infants may yield important information concerning nonstructural determinants of HIV-1 transmission from mother to infant.