Sialidase Activity in the Cervicovaginal Fluid Is Associated With Changes in Bacterial Components of Lactobacillus-Deprived Microbiota

INTRODUCTION

Sialidase activity in the cervicovaginal fluid (CVF) is associated with microscopic findings of bacterial vaginosis (BV). Sequencing of bacterial 16S rRNA gene in vaginal samples has revealed that the majority of microscopic BV cases fit into vaginal community-state type IV (CST IV), which was recently named "molecular-BV." Bacterial vaginosis-associated bacterial species, such as Gardnerella spp., may act as sources of CVF sialidases. These hydrolases lead to impairment of local immunity and enable bacterial adhesion to epithelial and biofilm formation. However, the impact of CVL sialidase on microbiota components and diversity remains unknown.

OBJECTIVE

To assess if CVF sialidase activity is associated with changes in bacterial components of CST IV.

METHODS

One hundred forty women were cross-sectionally enrolled. The presence of molecular-BV (CST IV) was assessed by V3-V4 16S rRNA sequencing (Illumina). Fluorometric assays were performed using 2-(4-methylumbelliferyl)-α-D-N-acetylneuraminic acid (MUAN) for measuring sialidase activity in CVF samples. Linear discriminant analysis effect size (LEfSe) was performed to identify the differently enriched bacterial taxa in molecular-BV according to the status of CVF sialidase activity.

RESULTS

Forty-four participants (31.4%) had molecular-BV, of which 30 (68.2%) had sialidase activity at detectable levels. A total of 24 bacterial taxa were enriched in the presence of sialidase activity, while just two taxa were enriched in sialidase-negative samples.

CONCLUSION

Sialidase activity in molecular-BV is associated with changes in bacterial components of the local microbiome. This association should be further investigated, since it may result in diminished local defenses against pathogens.

Vaginal Microbiota and Mucosal Pharmacokinetics of Tenofovir in Healthy Women Using a 90-Day Tenofovir/Levonorgestrel Vaginal Ring

Background

A relationship between the vaginal microbiota and tenofovir (TFV) concentrations and activity after topical administration has been previously reported.

Objective

CONRAD A15-138 was a randomized, placebo-controlled Phase I study aimed at characterizing the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of TFV and levonorgestrel (LNG) administered through a vaginal ring (IVR) for 90 days. Herein, we describe changes from baseline in the vaginal microbiota with IVR use and the impact of the vaginal microbiota on mucosal TFV PK.

Methods

The study screened 68 participants and randomized 47 (37 TFV/LNG, 10 placebo), assessing the vaginal microbiota by sequencing the V3–V4 regions of 16S rRNA genes prior to IVR insertion and monthly for 3 months. Concentrations of TFV in vaginal fluid (VF), and TFV and TFV-diphosphate (TFV-DP) in vaginal tissue, and modeled PD against HIV-1 in vitro were measured before and after treatment.

Results

There were no clinically significant changes in relative abundance of vaginal bacterial phylotypes from pre-insertion baseline at any month among active and placebo IVR users. There were no significant changes in community state type (CST) with IVR use. Participants with diverse, anaerobic CST IVA/B microbiota had higher in vivo release of TFV from the IVR compared to women with Lactobacillus-dominated (LbD) microbiota, who had expected in vivo TFV release rates. Median VF TFV concentrations were significantly higher among women with CST IVA/B microbiota in months 1 (3,135 ng/mg VF) and 2 (3,800 ng/mg). Women with LbD microbiota had significantly higher median VF TFV concentration (1,423 ng/mg) and median TFV (103 ng/mg) and TFV-DP (5,877 fmol/mg) tissue concentrations versus women with CST IVA/B microbiota at month 3. All women demonstrated a significant increase from pre-insertion baseline of in vitro HIV-1 inhibition by VF (p values <0.05). PD differences in tissue according to CST, however, were not statistically significant.

Conclusion

TFV/LNG IVR use did not change the vaginal microbiota nor increase the incidence of CST IVA/B. Vaginal microbiota, and in particular CST IVA/B, possibly through increased vaginal pH, impacted in vivo TFV release and cervicovaginal (CV) PK, but both PK and PD data suggest CV protection against HIV-1.

Clinical Trial Registration

ClinicalTrials.gov (#NCT03279120)

Insight into the ecology of vaginal bacteria through integrative analyses of metagenomic and metatranscriptomic data

Background

Vaginal bacterial communities dominated by Lactobacillus species are associated with a reduced risk of various adverse health outcomes. However, somewhat unexpectedly, many healthy women have microbiota that are not dominated by lactobacilli. To determine the factors that drive vaginal community composition we characterized the genetic composition and transcriptional activities of vaginal microbiota in healthy women.

Results

We demonstrate that the abundance of a species is not always indicative of its transcriptional activity and that impending changes in community composition can be predicted from metatranscriptomic data. Functional comparisons highlight differences in the metabolic activities of these communities, notably in their degradation of host produced mucin but not glycogen. Degradation of mucin by communities not dominated by Lactobacillus may play a role in their association with adverse health outcomes. Finally, we show that the transcriptional activities of L. crispatus, L. iners, and Gardnerella vaginalis vary with the taxonomic composition of the communities in which they reside. Notably, L. iners and G. vaginalis both demonstrate lower expression of their cholesterol-dependent cytolysins when co-resident with Lactobacillus spp. and higher expression when co-resident with other facultative and obligate anaerobes. The pathogenic potential of these species may depend on the communities in which they reside and thus could be modulated by interventional strategies.

Conclusions

Our results provide insight to the functional ecology of the vaginal microbiota, demonstrate the diagnostic potential of metatranscriptomic data, and reveal strategies for the management of these ecosystems.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13059-022-02635-9.

Serum antibodies to surface proteins of Chlamydia trachomatis as candidate biomarkers of disease: results from the Baltimore Chlamydia Adolescent/Young Adult Reproductive Management (CHARM) cohort

We previously observed that the nine-member family of autotransported polymorphic membrane proteins (Pmps) of Chlamydia trachomatis is variably expressed in cell culture. Additionally, C. trachomatis-infected patients display variable Pmp-specific serum antibody profiles indirectly suggesting expression of unique Pmp profiles is an adaptive response to host-specific stimuli during infection. Here, we propose that the host response to Pmps and other outer surface proteins may correlate with disease severity.

This study tests this hypothesis using an ELISA that measures serum IgG antibodies specific for the nine C. trachomatis Pmp subtypes and four immunodominant antigens (MOMP, OmcB, Hsp60, ClpP) in 265 participants of the Chlamydia Adolescent/Young Adult Reproductive Management (CHARM) cohort.

More C. trachomatis-infected females displayed high Pmp-specific antibody levels (cut-off Indexes) than males (35.9–40.7% of females vs. 24.2–30.0% of males), with statistical significance for PmpC, F and H (P&lt;0.05). Differences in Pmp-specific antibody profiles were not observed between C. trachomatis-infected females with a clinical diagnosis of pelvic inflammatory disease (PID) and those without. However, a statistically significant association between high levels of OmcB-specific antibody and a PID diagnosis (P&lt;0.05) was observed.

Using antibody levels as an indirect measure of antigen expression, our results suggest that gender- and/or site-specific (cervix in females vs. urethra in males) stimuli may control pmp expression in infected patients. They also support the possible existence of immune biomarkers of chlamydial infection associated with disease and underline the need for high resolution screening in human serum.

Altered Gut Microbiome and Fecal Immune Phenotype in Early Preterm Infants With Leaky Gut

Intestinal barrier immaturity, or "leaky gut", is the proximate cause of susceptibility to necrotizing enterocolitis in preterm neonates. Exacerbated intestinal immune responses, gut microbiota dysbiosis, and heightened barrier injury are considered primary triggers of aberrant intestinal maturation in early life. Inordinate host immunity contributes to this process, but the precise elements remain largely uncharacterized, leaving a significant knowledge gap in the biological underpinnings of gut maturation. In this study, we investigated the fecal cytokine profile and gut microbiota in a cohort of 40 early preterm infants <33-weeks-gestation to identify immune markers of intestinal barrier maturation. Three distinct microbiota types were demonstrated to be differentially associated with intestinal permeability (IP), maternal breast milk feeding, and immunological profiles. The Staphylococcus epidermidis- and Enterobacteriaceae-predominant microbiota types were associated with an elevated IP, reduced breast milk feeding, and less defined fecal cytokine profile. On the other hand, a lower IP was associated with increased levels of fecal IL-1α/β and a microbiota type that included a wide array of anaerobes with expanded fermentative capacity. Our study demonstrated the critical role of both immunological and microbiological factors in the early development of intestinal barrier that collectively shape the intestinal microenvironment influencing gut homeostasis and postnatal intestinal maturation in early preterm newborns.

The Effect of Gender-Affirming Medical Care on the Vaginal and Neovaginal Microbiomes of Transgender and Gender-Diverse People

Transgender and gender diverse individuals may seek gender-affirming medical care, such as hormone therapy or surgery, to produce primary and/or secondary sex characteristics that are more congruent with their gender. Gender-affirming medical care for transmasculine individuals can include testosterone therapy, which suppresses circulating estrogen and can lead to changes in the vaginal epithelium that are reminiscent of the post-menopausal period in cisgender females. Among transfeminine individuals, gender-affirming medical care can include vaginoplasty, which is the surgical creation of a vulva and neovaginal canal, commonly using penile and scrotal skin. The effect of gender-affirming medical care on the vagina of transmasculine individuals and on the neovagina of transfeminine individuals is poorly characterized. This review summarizes what is known of the epithelium and local microbiota of the testosterone-exposed vagina and the neovagina. We focus on potential pathogens and determinants of gynecological health and identify key knowledge gaps for future research.

Concomitant and productive genital infections by HSV-2 and HPV in two young women: A case report

Human papillomaviruses (HPVs), the most oncogenic virus known to humans, are often associated with Herpes Simplex Virus-2 (HSV-2) infections. The involvement of the latter in cervical cancer is controversial but its long-term infections might modulate the mucosal microenvironment in a way that favors carcinogenesis. We know little about coinfections between HSV-2 and HPVs, and studying the immunological and microbiological dynamics in the early stages of these infections may help identify or rule out potential interactions. We report two cases of concomitant productive, although asymptomatic, HSV-2 and HPV infections in young women (aged 20 and 25). The women were followed up for approximately a year, with clinical visits every two months and weekly self-samples. We performed quantitative analyses of their HSV-2 and HPV viral loads, immunological responses (IgG and IgM antibodies and local cytokines expression profiles), vaginal microbiota composition, as well as demographic and behavior data. We detect interactions between virus loads, immune response, and the vaginal microbiota, which improve our understanding of HSV-2 and HPVs’ coinfections and calls for further investigation with larger cohorts.

Vaginal microbiota of American Indian women and associations with measures of psychosocial stress

Molecular-bacterial vaginosis (BV) is characterized by low levels of vaginal Lactobacillus species and is associated with higher risk of sexually transmitted infections (STI). Perceived psychosocial stress is associated with increased severity and persistence of infections, including STIs. American Indians have the highest rates of stress and high rates of STIs. The prevalence of molecular-BV among American Indian women is unknown. We sought to evaluate measures of psychosocial stress, such as historic loss (a multigenerational factor involving slavery, forced removal from one's land, legally ratified race-based segregation, and contemporary discrimination) and their association with the vaginal microbiota and specific metabolites associated with BV, in 70 Northwestern Plains American Indian women. Demographics, perceived psychosocial stressors, sexual practices, and known BV risk factors were assessed using a modified version of the American Indian Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project survey. Self-collected mid-vaginal swabs were profiled for bacterial composition by 16S rRNA gene amplicon sequencing and metabolites quantified by targeted liquid-chromatography mass spectrometry. Sixty-six percent of the participants were classified as having molecular-BV, with the rest being either dominated by L. crispatus (10%) or L. iners (24%). High levels of lifetime trauma were associated with higher odds of having molecular-BV (adjusted Odds Ratio (aOR): 2.5, 95% Credible Interval (CrI): 1.1-5.3). Measures of psychosocial stress, including historic loss and historic loss associated symptoms, were significantly associated with lifestyle and behavioral practices. Higher scores of lifetime trauma were associated with increased concentrations of spermine (aFC: 3.3, 95% CrI: 1.2-9.2). Historic loss associated symptoms and biogenic amines were the major correlates of molecular-BV. Historical loss associated symptoms and lifetime trauma are potentially important underlying factors associated with BV.

A non-optimal cervicovaginal microbiota in pregnancy is associated with a distinct metabolomic signature among non-Hispanic Black individuals

Biomechanical and molecular processes of premature cervical remodeling preceding spontaneous preterm birth (sPTB) likely result from interactions between the cervicovaginal microbiota and host immune responses. A non-optimal cervicovaginal microbiota confers increased risk of sPTB. The cervicovaginal space is metabolically active in pregancy; microbiota can produce, modify, and degrade metabolites within this ecosystem. We establish that cervicovaginal metabolomic output clusters by microbial community in pregnancy among Black individuals, revealing increased metabolism within the amino acid and dipeptide pathways as hallmarks of a non-optimal microbiota. Few differences were detected in metabolomic profiles when stratified by birth outcome. The study raises the possibility that metabolites could distinguish women with greater risk of sPTB among those with similar cervicovaginal microbiota, and that metabolites within the amino acid and carbohydrate pathways may play a role in this distinction.

Perceived Stress and Molecular Bacterial Vaginosis in the National Institutes of Health Longitudinal Study of Vaginal Flora

Vaginal microbiota provide the first line of defense against urogenital infections primarily through protective actions of Lactobacillus species Perceived stress increases susceptibility to infection through several mechanisms, including suppression of immune function. We investigated whether stress was associated with deleterious changes to vaginal bacterial composition in a subsample of 572 women in the Longitudinal Study of Vaginal Flora, sampled from 1999 through 2002. Using Cox proportional hazards models, both unadjusted and adjusted for sociodemographic factors and sexual behaviors, we found that participants who exhibited a 5-unit-increase in Cohen's Perceived Stress Scale had greater risk (adjusted hazard ratio (HR) = 1.40, 95% confidence interval (CI): 1.13, 1.74) of developing molecular bacterial vaginosis (BV), a state with low Lactobacillus abundance and diverse anaerobic bacteria. A 5-unit increase in stress score was also associated with greater risks of transitioning from the L. iners-dominated community state type (26% higher) to molecular-BV (adjusted HR = 1.26, 95% CI: 1.01, 1.56) or maintaining molecular-BV from baseline (adjusted HR = 1.23, 95% CI: 1.01, 1.47). Inversely, women with baseline molecular-BV reporting a 5-unit stress increase were less likely to transition to microbiota dominated by L. crispatus, L. gasseri, or L. jensenii (adjusted HR = 0.81, 95% CI: 0.68, 0.99). These findings suggest that psychosocial stress is associated with vaginal microbiota composition, inviting a more mechanistic exploration of the relationship between psychosocial stress and molecular-BV.

The composition of human vaginal microbiota transferred at birth affects offspring health in a mouse model

Newborns are colonized by maternal microbiota that is essential for offspring health and development. The composition of these pioneer communities exhibits individual differences, but the importance of this early-life heterogeneity to health outcomes is not understood. Here we validate a human microbiota-associated model in which fetal mice are cesarean delivered and gavaged with defined human vaginal microbial communities. This model replicates the inoculation that occurs during vaginal birth and reveals lasting effects on offspring metabolism, immunity, and the brain in a community-specific manner. This microbial effect is amplified by prior gestation in a maternal obesogenic or vaginal dysbiotic environment where placental and fetal ileum development are altered, and an augmented immune response increases rates of offspring mortality. Collectively, we describe a translationally relevant model to examine the defined role of specific human microbial communities on offspring health outcomes, and demonstrate that the prenatal environment dramatically shapes the postnatal response to inoculation.

Vaginal microbiome components as correlates of cervical human papillomavirus infection

BACKGROUND

The interplay between vaginal microbiome and human papillomavirus (HPV) remains unclear, partly due to heterogeneity of the microbiota.

METHODS

We used data from 546 women enrolled in a cross-sectional study conducted in five Brazilian regions. We genotyped vaginal samples for HPV and sequenced V3-V4 region of 16S rRNA gene for vaginal microbiome analysis. We used stepwise logistic regression to construct two linear scores to predict high-risk HPV (hrHPV) positivity: one based exclusively on presence of individual bacterial taxa (microbiome-based [MB] score) and the other exclusively on participants' sociodemographic, behavioral and clinical (SBC) characteristics. The MB score combined coefficients of 30 (out of 116) species. The SBC score retained six out of 25 candidate variables. We constructed receiver operating characteristic curves for the scores as hrHPV correlates and compared areas under the curve (AUC) and 95% confidence intervals (CI).

RESULTS

Overall, prevalence of hrHPV was 15.8%, and 26.2% had a Lactobacillus-depleted microbiome. The AUCs were 0.8022 (CI:0.7517-0.8527) for MB score and 0.7027 (CI:0.6419-0.7636) for SBC score (P=0.0163).

CONCLUSIONS

The proposed MB score is strongly correlated with hrHPV positivity - exceeding the predictive value of behavioral variables - suggesting its potential as an indicator of infection and possible value for clinical risk stratification.

Temporal Changes in Vaginal Microbiota and Genital Tract Cytokines Among South African Women Treated for Bacterial Vaginosis

The standard treatment for bacterial vaginosis (BV) with oral metronidazole is often ineffective, and recurrence rates are high among African women. BV-associated anaerobes are closely associated with genital inflammation and HIV risk, which underscores the importance of understanding the interplay between vaginal microbiota and genital inflammation in response to treatment. In this cohort study, we therefore investigated the effects of metronidazole treatment on the vaginal microbiota and genital cytokines among symptomatic South African women with BV [defined as Nugent score (NS) ≥4] using 16S rRNA gene sequencing and multiplex bead arrays. Among 56 BV-positive women, we observed short-term BV clearance (NS <4) in a proportion of women six weeks after metronidazole treatment, with more than half of these experiencing recurrence by 12 weeks post-treatment. BV treatment temporarily reduced the relative abundance of BV-associated anaerobes (particularly Gardnerella vaginalis and Atopobium vaginae) and increased lactobacilli species (mainly L. iners), resulting in significantly altered mucosal immune milieu over time. In a linear mixed model, the median concentrations of pro-inflammatory cytokines and chemokines were significantly reduced in women who cleared BV compared to pre-treatment. BV persistence and recurrence were strongly associated with mucosal cytokine profiles that may increase the risk of HIV acquisition. Concentrations of these cytokines were differentially regulated by changes in the relative abundance of BVAB1 and G. vaginalis. We conclude that metronidazole for the treatment of BV induced short-term shifts in the vaginal microbiota and mucosal cytokines, while treatment failures promoted persistent elevation of pro-inflammatory cytokine concentrations in the genital tract. These data suggest the need to improve clinical management of BV to minimize BV related reproductive risk factors.

Vaginal cytokine profile and microbiota before and after lubricant use compared with condomless vaginal sex: a preliminary observational study

BACKGROUND

Limited data suggest that personal lubricants may damage the vaginal mucosal epithelium, alter the vaginal microbiota, and increase inflammation. We compared vaginal cytokine profiles and microbiota before and after vaginal lubricant use and condomless vaginal sex.

METHODS

Reproductive-age women were recruited to a 10-week observational cohort study and were asked to self-collect vaginal samples and behavioral diaries daily. This nested case-control analysis utilized samples collected before and after self-reported condomless sexual activity with lubricants (22 case participants) and without lubricants (22 control participants). Controls were matched to cases on race/ethnicity. Microbiota composition was characterized by sequencing amplicons of the 16S rRNA gene V3-V4 regions. Cytokine concentrations were quantified using a magnetic bead 41-plex panel assay and read using a Bio-Plex 200 array reader. Wilcoxon signed-rank tests were used to assess baseline differences in vaginal cytokines between cases and controls as well as differences pre- and post-exposure. Linear mixed effects models were used to examine differences in relative post-to-pre change in each individual cytokine between matched cases and controls. Similar analyses were conducted for the microbiota data.

RESULTS

Mean age was 29.8 years (SD 6.8), and 63.6% were African American. There were few statistically significant changes in cytokines or microbiota before and after exposure in cases or controls. In mixed-effects modeling, the mean relative post-to-pre change of cytokines was higher in cases vs. controls for macrophage derived chemokine (MDC) (p = 0.03). The microbiota data revealed no significant changes when measured by similarity scores, diversity indexes and descriptive community state types (CST) transition analyses. However, post sexual activity, the mean relative abundance of L. crispatus decreased for those who used lubricants (particularly those who were L. iners-dominated prior to exposure).

CONCLUSIONS

Although there were overall few differences in the vaginal microbiota and cytokine profiles of lubricant users and controls before and after condomless vaginal sex, there was a trend toward decreases in relative abundance of L. crispatus following use of lubricant. Future larger studies that take into account osmolarity and composition of lubricants may provide additional insights.

Characteristics associated with Lactobacillus iners-dominated vaginal microbiota

OBJECTIVE

The protective role of Lactobacillus iners in the vaginal microbiota has been questioned. Recent studies have shown that L. iners is the dominating taxon in a large subset of women worldwide. The aim of this study was to identify sociodemographic, behavioural and clinical variables associated with L. iners-dominated community state type (CST) III in Brazilian women of reproductive age.

PARTICIPANTS AND METHODS

This study leveraged microbiota compositional data generated by sequencing of the V3-V4 16S rRNA gene from vaginal samples collected from 442 participants enrolled in a previous cross-sectional study that included 609 women in five geographical regions of Brazil. A total of 167 (27.4%) participants were excluded from the current study as they did not present a Lactobacillus-dominated vaginal microbiota. Data on sociodemographic and behavioural characteristics of the study population were obtained through face-to-face interviews. Participants were assigned to two study groups: those with L. iners-dominated CST III (n=222) and those with three distinct CSTs (I, II or V) dominated by another Lactobacillus spp. (n=220). Logistic regression analysis using a stepwise method was performed to test association between CST III and participants' characteristics, considering their OR and 95% CIs.

RESULTS

Among the population characteristics assessed, L. iners-dominated CST III was independently associated with having two or more sexual partners (OR 3.27; 95% CI 1.50 to 7.11) and microscopic detection of Candida sp. on vaginal smears (OR 2.24; 95% CI 1.02 to 4.89). Other characteristics were inversely associated with CST III, including condom use (OR 0.59; 95% CI 0.38 to 0.91), higher educational level (OR 0.61; 95% CI 0.41 to 0.91) and diet containing milk/dairy intake (OR 0.43; 95% CI 0.20 to 0.90).

CONCLUSION

Unprotected sex practices, number of sexual partners and lower educational levels may be useful for identifying women with L. iners-dominated microbiota and its suboptimal protective properties. L. iners microbiota does not seem to provide optimal protection against Candida sp. colonisation, warranting further investigation.

Association of E484K spike protein mutation with SARS-CoV-2 infection in vaccinated persons---Maryland, January - May 2021

Among 9,048 people infected with SARS-CoV-2 between January-May, 2021 in Maryland, in regression-adjusted analysis, SARS-CoV-2 viruses carrying the spike protein mutation E484K were disproportionately prevalent among persons infected after full vaccination against COVID-19 as compared to infected persons who were not fully vaccinated (aOR 1.96, 95% CI, 1.36 to 2.83).

Using Innovation to Address Adolescent and Young Adult Health Disparities in Pelvic Inflammatory Disease: Design of the Technology Enhanced Community Health Precision Nursing (TECH-PN) Trial

New approaches to pelvic inflammatory disease (PID) care among adolescents and young adults (AYAs) that optimize self-care and personalize treatment are warranted to address age and racial-ethnic PID-related health disparities. Here we describe the 13-month preliminary feasibility and acceptability outcomes of recruitment, retention, and intervention delivery for Technology Enhanced Community Health Precision Nursing (TECH-PN) randomized controlled trial. Urban AYAs 13-25 years assigned female sex at birth with acute mild-moderate PID provided baseline and follow-up interview data and vaginal specimens for sexually transmitted infection (STI), cytokine, and microbiota assessment. All participants received medications and text-messaging support. Participants were block randomized to either control or intervention. Control participants received 1 community nursing visit with self-management for interim care per national guidelines. Intervention participants received unlimited precision care services driven by interim STI and macrolide resistance testing results by an advanced practice provider. In the first 13 months, 75.2% patients were eligible, and 76.1% of eligible patients enrolled. Of the participants, 94% completed the intervention and 96%, 91%, and 89%, respectively, completed their 14-, 30-, and 90-day visits. Baseline laboratory results revealed infection rates that were highest for Mycoplasma genitalium (45%) followed by Chlamydia trachomatis (31%). Preliminary enrollment, STI, intervention delivery, and retention data demonstrate the feasibility and acceptability of the TECH-PN intervention and support rationale for precision care for PID among urban AYAs. ClinicalTrials.gov Identifier. NCT03828994.

Associations of public water system trihalomethane exposure during pregnancy with spontaneous preterm birth and the cervicovaginal microbial-immune state

BACKGROUND

Water total trihalomethanes (TTHMs) are disinfectant byproducts found in municipal water supplies. TTHM exposure has been linked to cancer and may be associated with adverse reproductive outcomes. A non-optimal cervicovaginal microbiota and low cervicovaginal beta-defensin-2 levels are associated with increased risk of spontaneous preterm birth. Whether TTHM exposure increases the risk of spontaneous preterm birth or alters the cervicovaginal microbial or immune state is unknown.

OBJECTIVE

Investigate associations of water TTHM levels with spontaneous preterm birth, a non-optimal cervicovaginal microbiota, and beta-defensin-2 levels in a completed, diverse, urban pregnancy cohort. We hypothesized that higher TTHM levels would be associated with spontaneous preterm birth, a non-optimal cervicovaginal microbiota, and lower beta-defensin-2 levels.

DESIGN

Methods: This was a secondary analysis of participants (n = 474) in the Motherhood & Microbiome (M&M) study (n = 2000), who lived in Philadelphia and had cervicovaginal samples analyzed for cervicovaginal microbiota composition and beta-defensin-2 levels. The microbiota was classified into community state types (CSTs). CST IV (non-optimal microbiota) is characterized by a paucity of Lactobacillus species and wide array of anaerobes. Municipal water TTHM levels were obtained from 16 sites monthly across the city of Philadelphia to establish mean residential water supply levels for each participant for the first four months of pregnancy (prior to vaginal swab collection at 16-20 weeks' gestation). Associations of water TTHM levels with spontaneous preterm birth and a non-optimal cervicovaginal microbiota birth were analyzed using multivariable logistic regression. Multivariable linear regression was used to model associations of water TTHM levels with log-transformed cervicovaginal beta-defensin-2 levels. Since water TTHM levels vary by season and beta-defensin-2 levels have been shown to differ by race, stratified models by warm (April-September) and cold (October-March) seasons as well as by self-identified race were utilized.

RESULTS

Participants' water supply TTHM levels (mean μg/L [SD]) were higher in the warm (53.5 [9.4]) than cold (33.4 [7.5]) season (p < 0.0001). TTHM levels were non-significantly higher among Black participants than non-Black participants (44.8 [13.5] vs. 41.8 [11.8], p = 0.07). No associations were detected between TTHM with spontaneous preterm birth (per SD increment of TTHM, aOR 0.94, 95%CI: 0.66, 1.34) or with CST IV (aOR 0.94, 95%CI: 0.86, 1.16). Counter to our hypothesis, we observed positive associations of water TTHM with log-transformed cervicovaginal beta-defensin-2 levels in unadjusted models (β 0.20 [95%CI: 0.02, 0.39]) per SD increment of TTHM), but the association was null after adjustment for season. However, in models adjusted for covariates including season and stratified by race, TTHM was significantly associated with lower beta-defensin-2 levels among non-Black participants (β -0.75 [95%CI: -1.43, -0.08]) but not among Black participants (β 0.17 [95%CI: -0.15, 0.49]), interaction p = 0.013).

CONCLUSION

We did not detect associations of water TTHM levels with spontaneous preterm birth or the structure of the cervicovaginal microbiota. However, the finding of a significant interaction between TTHM and race on beta-defensin-2 levels suggest that environmental exposures may contribute to differences in reproductive tract innate immune function by race. Future studies to delineate environmental contributions to the cervicovaginal microbial-immune state, a potentially important biologic underpinning for preterm birth, are warranted.

Supporting scale-up of COVID-19 RT-PCR testing processes with discrete event simulation

Testing is critical to mitigating the COVID-19 pandemic, but testing capacity has fallen short of the need in the United States and elsewhere, and long wait times have impeded rapid isolation of cases. Operational challenges such as supply problems and personnel shortages have led to these bottlenecks and inhibited the scale-up of testing to needed levels. This paper uses operational simulations to facilitate rapid scale-up of testing capacity during this public health emergency. Specifically, discrete event simulation models were developed to represent the RT-PCR testing process in a large University of Maryland testing center, which retrofitted high-throughput molecular testing capacity to meet pandemic demands in a partnership with the State of Maryland. The simulation models support analyses that identify process steps which create bottlenecks, and evaluate “what-if” scenarios for process changes that could expand testing capacity. This enables virtual experimentation to understand the trade-offs associated with different interventions that increase testing capacity, allowing the identification of solutions that have high leverage at a feasible and acceptable cost. For example, using a virucidal collection medium which enables safe discarding of swabs at the point of collection removed a time-consuming “deswabbing” step (a primary bottleneck in this laboratory) and nearly doubled the testing capacity. The models are also used to estimate the impact of demand variability on laboratory performance and the minimum equipment and personnel required to meet various target capacities, assisting in scale-up for any laboratories following the same process steps. In sum, the results demonstrate that by using simulation modeling of the operations of SARS-CoV-2 RT-PCR testing, preparedness planners are able to identify high-leverage process changes to increase testing capacity.

Assessing the Concordance Between Urogenital and Vaginal Microbiota: Can Urine Specimens Be Used as a Proxy for Vaginal Samples?

Background

The vaginal microbiota play a key role in defense against reproductive tract infections; however, many population-based women's health studies do not collect vaginal samples. Molecular examinations of urine samples have revealed common vaginal bacteria. We sought to assess the extent that community state type assignments of archived random-catch and clean-catch urine samples agreed with the paired vaginal samples in both reproductive-age and peri/post-menopausal women.

Results

Using archived samples, we evaluated the microbiota concordance among women in three studies: two with paired mid-vaginal/random-catch urine (N=91 reproductive-age participants and N=13 peri/post-menopausal participants), and one with paired mid-vaginal/clean-catch urine (N=99 reproductive-age participants). Microbiota composition was characterized by sequencing amplicons of the 16S rRNA gene V3-V4 regions and assigned to community state types. Similarity of paired samples was gauged using agreement of community state types and Yue-Clayton θ indices. Analysis of Composition of Microbiomes II indicated which taxa were differently relatively abundant in paired vaginal and urine samples. In reproductive-age women, random-catch and clean-catch urines were 89.0% and 86.9% concordant on five community state types with paired mid-vaginal swabs, and Kappa statistics indicated almost perfect agreement (κ_random-catch=.85, κ_clean-catch=.81, p<0.0001). A small number of pairs of samples were discordant (23/190, 12%), and discordant pairs tended to be between samples classified to L. iners-dominated and/or low-Lactobacillus states. Concordance and agreement remained similar when dichotomizing the microbiota to Lactobacillus-dominated versus low-Lactobacillus microbiota, as well as when evaluating separately the three subtypes of the low-Lactobacillus community state type IV. Median similarity of paired urine/vaginal samples was high (θ_random-catch=.85, θ_clean-catch=.88), and a comparison of the random-catch and clean-catch similarity scores showed no significant difference (p=.80). Concordance and similarity were lower for peri/post-menopausal women, but agreement remained substantial (76.9% concordant, κ_random-catch= 0.64, θ_random-catch=.62). Taxonomic-level analysis confirmed these findings.

Conclusions

Random-catch and clean-catch urine samples showed substantial agreement on bacterial composition to paired mid-vaginal samples, indicating that the genitourinary microbiota may be a reliable proxy for assessing the overall composition of the vaginal microbiota via community state types. This data suggests that urine samples can, with proper interpretation, be utilized as a surrogate for developing preliminary data and hypothesis-generating studies.

Observational cohort study of the effect of a single lubricant exposure during transvaginal ultrasound on cell-shedding from the vaginal epithelium

The outer layers of the vaginal epithelium (VE) are important because they accumulate glycogen which, under optimal conditions, Lactobacillus spp. consume to grow and acidify the vaginal microenvironment with lactic acid. We hypothesized that exposure to lubricant, for example in the conduct of a transvaginal ultrasound (TVUS), may contribute to the shedding of mature epithelial cells, exposing immature cells. Cervicovaginal fluid (CVF) was sampled at four time points by menstrual cup (Softdisc™) from 50 women referred for TVUS, during which a controlled volume of lubricant was applied to the TVUS wand. Samples were collected (1) immediately before TVUS and (2) 6-12 hours, (3) within one week, and (4) two weeks after TVUS. Clinical vaginal lubricants are similar to commercial lubricants, and often have a high osmolality or pH, and contain bactericides such as methylparaben and propylparaben. The number and maturity of epithelial cells in each CVF sample were measured by quantitative and differential fluorimetry (maturity index, MI). Comparisons of cell-counts and maturity were made by paired Wilcoxon signed-rank tests. Among women with a high pre-TVUS MI (> 3), there was a decrease in median cell-count and mean MI in the sample collected 6-12 hours after TVUS (p<0.001, n = 26 and p < 0.001, n = 26, respectively). For these women, cell-count and MI remained lower in the sample collected within the subsequent week (p<0.001, n = 29 and p<0.01, n = 29, respectively), and MI remained lower in the sample collected within two weeks of TVUS (p<0.01, n = 25), compared to the pre-TVUS sample. Among participants with a low pre-TVUS MI (< 3), cell-count was higher in the sample collected within two weeks of TVUS compared to the pre-TVUS sample (p = 0.03, n = 15), but no significant changes in MI were observed. Results were similar when restricted to reproductive-age women. This preliminary data indicates hypertonic vaginal lubricants may increase vaginal epithelial cell shedding.

Association of Vaginal Microbiota with Signs and Symptoms of the Genitourinary Syndrome of Menopause across Reproductive Stages

The genitourinary syndrome of menopause (GSM) describes signs and symptoms resulting from effects of estrogen deficiency on the female genitourinary tract, including the vagina, labia, urethra, and bladder. Signs/symptoms associated with GSM may occur during any reproductive stage from multiple etiologies but are most common during menopause due to low estrogen. Vaginal microbiota, particularly Lactobacillus spp., are beneficial to the female genital tract; however, their abundance declines during menopause. We aimed to longitudinally assess vaginal microbiota characterized by 16S rRNA gene amplicon sequencing and GSM-associated endpoints across reproductive stages. In a two-year cohort study of 750 women aged 35-60 years at enrollment and 2,111 semiannual person-visits, low-Lactobacillus vaginal microbiota communities were observed at 21.2% (169/798), 22.9% (137/597), and 49.7% (356/716) of person-visits among pre-, peri-, and postmenopausal women, respectively (p<.001). Compared to communities that have high Gardnerella vaginalis relative abundance and diverse anaerobes, the following communities were associated with a lower covariate-adjusted odds of vaginal atrophy: L. crispatus-dominated communities among postmenopausal women (odds ratio[OR]=0.25; 95% confidence interval[CI], 0.08, 0.81), L. gasseri/L. jensenii (OR=0.21; 95%CI, 0.05, 0.94) and L. iners (OR=0.21; 95%CI, 0.05, 0.85) among perimenopausal women, and L. iners-dominated communities (OR=0.18; 95%CI, 0.04, 0.76) among premenopausal women. Postmenopausal women with L. gasseri/L. jensenii-dominated communities had the lowest odds of vaginal dryness (OR=0.36; 95%CI, 0.12, 1.06) and low libido (OR=0.28; 95%CI, 0.10, 0.74). Findings for urinary incontinence were inconsistent. Associations of vaginal microbiota with GSM signs/symptoms are most evident after menopause, suggesting an avenue for treatment and prevention.

Biogenic Amines Increase the Odds of Bacterial Vaginosis and Affect the Growth of and Lactic Acid Production by Vaginal Lactobacillus spp

Bacterial vaginosis (BV) is the most common vaginal disorder of reproductive-aged women, yet its etiology remains enigmatic. One clinical symptom of BV, malodor, is linked to the microbial production of biogenic amines (BA). Using targeted liquid chromatography mass spectrometry, we analyzed 149 longitudinally collected vaginal samples to determine the in vivo concentrations of the most common BAs and then assessed their relationship to BV and effect upon the growth kinetics of axenically cultured vaginal Lactobacillus species. Increases in cadaverine, putrescine, and tyramine were associated with greater odds of women transitioning from L. crispatus-dominated vaginal microbiota to microbiota that have a paucity of Lactobacillus spp. and from Nugent scores of 0 to 3 to Nugent scores of 7 to 10, consistent with BV. Exposure to putrescine lengthened the lag time and/or slowed the growth of all vaginal Lactobacillus spp. except L. jensenii 62G. L. iners AB107's lag time was lengthened by cadaverine but reduced in the presence of spermidine and spermine. The growth rate of L. crispatus VPI 3199 was slowed by cadaverine and tyramine, and strain-specific responses to spermine and spermidine were observed. BAs were associated with reduced production of d- and l-lactic acid by vaginal Lactobacillus spp., and this effect was independent of their effect upon Lactobacillus species growth. The exceptions were higher levels of d- and l-lactic acid by two strains of L. crispatus when grown in the presence of spermine. Results of this study provide evidence of a direct impact of common biogenic amines on vaginal Lactobacillus spp.IMPORTANCELactobacillus spp. are credited with providing the primary defense against gynecological conditions, including BV, most notably through the acidification of the vaginal microenvironment, which results from their production of lactic acid. The microbial production of BAs has been hypothesized to play a mechanistic role in diminishing Lactobacillus species-mediated protection, enabling the colonization and outgrowth of diverse anaerobic bacterial species associated with BV. Here, we demonstrate that in vivo increases in the most commonly observed BAs are associated with a loss of Lactobacillus spp. and the development of BV, measured by Nugent score. Further, we show that BAs formed by amino acid decarboxylase enzymes negatively affect the growth of type strains of the most common vaginal Lactobacillus spp. and separately alter their production of lactic acid. These results suggest that BAs destabilize vaginal Lactobacillus spp. and play an important and direct role in diminishing their protection of the vaginal microenvironment.

Effect of a Nonoptimal Cervicovaginal Microbiota and Psychosocial Stress on Recurrent Spontaneous Preterm Birth

OBJECTIVE

While select cervicovaginal microbiota and psychosocial factors have been associated with spontaneous preterm birth, their effect on the risk of recurrence remains unclear. It is also unknown whether psychosocial factors amplify underlying biologic risk. This study sought to determine the effect of nonoptimal cervicovaginal microbiota and perceived stress on the risk of recurrent spontaneous preterm birth.

STUDY DESIGN

This was a secondary analysis of a prospective pregnancy cohort, Motherhood and Microbiome. The Cohen's Perceived Stress Scale (PSS-14) was administered and cervical swabs were obtained between 16 and 20 weeks of gestation. PSS-14 scores ≥30 reflected high perceived stress. We analyzed cervicovaginal microbiota using 16S rRNA sequencing and classified microbial communities into community state types (CSTs). CST IV is a nonoptimal cervicovaginal microbial community characterized by anaerobes and a lack of Lactobacillus. The final cohort included a predominantly non-Hispanic Black population of women with prior spontaneous preterm birth who had recurrent spontaneous preterm birth or term birth and had stress measurements (n = 181). A subanalysis was performed in the subset of these women with cervicovaginal microbiota data (n = 74). Multivariable logistic regression modeled adjusted associations between CST IV and recurrent spontaneous preterm birth, high stress and recurrent spontaneous preterm birth, as well as high stress and CST IV.

RESULTS

Among the 181 women with prior spontaneous preterm birth, 45 (24.9%) had high perceived stress. We did not detect a significant association between high stress and recurrent spontaneous preterm birth (adjusted odds ratio [aOR] 1.67, 95% confidence interval [CI]: 0.73-3.85). Among the 74 women with prior spontaneous preterm birth and cervicovaginal microbiota analyzed, 29 (39.2%) had CST IV; this proportion differed significantly among women with recurrent spontaneous preterm birth (51.4%) compared with women with term birth (28.2%) (p = 0.04). In models adjusted for race and marital status, the association between CST IV and recurrent spontaneous preterm birth persisted (aOR 3.58, 95% CI: 1.25-10.24). There was no significant interaction between stress and CST IV on the odds of spontaneous preterm birth (p = 0.328). When both stress and CST IV were introduced into the model, their associations with recurrent spontaneous preterm birth were slightly stronger than when they were in the model alone. The aOR for stress with recurrent spontaneous preterm birth was 2.02 (95% CI: 0.61-6.71) and for CST IV the aOR was 3.83 (95% CI: 1.30-11.33). Compared to women with neither of the two exposures, women with both high stress and CST IV had the highest odds of recurrent spontaneous preterm birth (aOR = 6.01, 95% CI: 1.002-36.03).

CONCLUSION

Among a predominantly non-Hispanic Black cohort of women with a prior spontaneous preterm birth, a nonoptimal cervicovaginal microbiota is associated with increased odds of recurrent spontaneous preterm birth. Adjustment for perceived stress may amplify associations between CST IV and recurrent spontaneous preterm birth. Identification of modifiable social or behavioral factors may unveil novel nonpharmacologic interventions to decrease recurrent spontaneous preterm birth among women with underlying biologic risk.

KEY POINTS

· CST IV, a nonoptimal microbiota, is associated with increased odds of recurrent spontaneous preterm birth.. · Adjustment for perceived stress amplified associations between CST IV and recurrent spontaneous preterm birth.. · Identification of modifiable psychosocial factors may unveil novel nonpharmacologic interventions to decrease recurrent preterm birth..