Antibody Response to the Sneathia vaginalis Cytopathogenic Toxin A during Pregnancy.

Sneathia vaginalis is a Gram-negative vaginal species that is associated with pregnancy complications. It produces cytopathogenic toxin A (CptA), a pore-forming toxin. To determine whether CptA is expressed in vivo and to examine the mucosal Ab response to the toxin, we examined human midvaginal swab samples obtained during pregnancy for IgM, IgA, and IgG Abs with CptA affinity. This subcohort study included samples from 93 pregnant people. S. vaginalis relative abundance was available through 16S rRNA survey. There were 22 samples from pregnancies that resulted in preterm birth in which S. vaginalis relative abundance was <0.005%, 22 samples from pregnancies that resulted in preterm birth with S. vaginalis ≥0.005%, 24 samples from pregnancies that resulted in term birth with S. vaginalis <0.005%, and 25 samples from pregnancies that resulted in term birth with S. vaginalis ≥0.005%. IgM, IgA, and IgG with affinity for CptA were assessed by ELISA. The capacity for the samples to neutralize CptA was quantified by hemolysis assay. All three Ab isotypes were detectable within different subsets of the samples. There was no significant association between relative abundance of S. vaginalis and the presence of any Ab isotype. The majority of vaginal swab samples containing detectable levels of anti-CptA Abs neutralized the hemolytic activity of CptA, with the strongest correlation between IgA and neutralizing activity. These results demonstrate that S. vaginalis produces CptA in vivo and that CptA is recognized by the host immune defenses, resulting in the production of Abs with toxin-neutralizing ability.

Genomes of Endotrypanum monterogeii from Panama and Zelonia costaricensis from Brazil: Expansion of Multigene Families in Leishmaniinae Parasites That Are Close Relatives of Leishmania spp.

The Leishmaniinae subfamily of the Trypanosomatidae contains both genus Zelonia (monoxenous) and Endotrypanum (dixenous). They are amongst the nearest known relatives of Leishmania, which comprises many human pathogens widespread in the developing world. These closely related lineages are models for the genomic biology of monoxenous and dixenous parasites. Herein, we used comparative genomics to identify the orthologous groups (OGs) shared among 26 Leishmaniinae species to investigate gene family expansion/contraction and applied two phylogenomic approaches to confirm relationships within the subfamily. The Endotrypanum monterogeii and Zelonia costaricensis genomes were assembled, with sizes of 29.9 Mb and 38.0 Mb and 9.711 and 12.201 predicted protein-coding genes, respectively. The genome of E. monterogeii displayed a higher number of multicopy cell surface protein families, including glycoprotein 63 and glycoprotein 46, compared to Leishmania spp. The genome of Z. costaricensis presents expansions of BT1 and amino acid transporters and proteins containing leucine-rich repeat domains, as well as a loss of ABC-type transporters. In total, 415 and 85 lineage-specific OGs were identified in Z. costaricensis and E. monterogeii. The evolutionary relationships within the subfamily were confirmed using the supermatrix (3384 protein-coding genes) and supertree methods. Overall, this study showed new expansions of multigene families in monoxenous and dixenous parasites of the subfamily Leishmaniinae.

Prevalence and incidence of sexually transmitted infections among South African women initiating injectable and long-acting contraceptives.

BACKGROUND: South Africa is among the countries with the highest prevalence of sexually transmitted infections (STIs), including Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). In 2017, there were an estimated 6 million new CT, 4.5 million NG and 71 000 Treponema pallidum infections among South African men and women of reproductive age. METHODS: We evaluated STI prevalence and incidence and associated risk factors in 162 women aged 18-33 years old, residing in eThekwini and Tshwane, South Africa who were part of the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial. Women were randomised to use depot medroxyprogesterone acetate (n = 53), copper intrauterine device (n = 51), or levonorgestrel (n = 58) implant. Lateral vaginal wall swab samples were collected prior to contraceptive initiation and at months one and three following contraceptive initiation for STI testing. RESULTS: There were no significant differences in STI incidence and prevalence across contraceptive groups. At baseline, 40% had active STIs (CT, NG, Trichomonas vaginalis (TV), Mycoplasma genitalium (MG) or herpes simplex virus-2 shedding across all age groups- 18-21 years (46%), 22-25 years (42%) and 26-33 years (29%). The incidence of STIs during follow-up was exceptionally high (107.9/100 women-years [wy]), with younger women (18-21 years) more likely to acquire CT (75.9/100 wy) compared to 26-33 year olds (17.4/100 wy; p = 0.049). TV incidence was higher in the 26-33 year old group (82.7/100 wy) compared to the 18-21 year olds (8.4/100 wy; p = 0.01). CONCLUSIONS: Although the study participants received extensive counselling on the importance of condom use, this study highlights the high prevalence and incidence of STIs in South African women, especially amongst young women, emphasising the need for better STI screening and management strategies.

Microdiversity of the vaginal microbiome is associated with preterm birth.

Preterm birth (PTB) is the leading cause of neonatal morbidity and mortality. The vaginal microbiome has been associated with PTB, yet the mechanisms underlying this association are not fully understood. Understanding microbial genetic adaptations to selective pressures, especially those related to the host, may yield insights into these associations. Here, we analyze metagenomic data from 705 vaginal samples collected during pregnancy from 40 women who delivered preterm spontaneously and 135 term controls from the Multi-Omic Microbiome Study-Pregnancy Initiative. We find that the vaginal microbiome of pregnancies that ended preterm exhibited unique genetic profiles. It was more genetically diverse at the species level, a result which we validate in an additional cohort, and harbored a higher richness and diversity of antimicrobial resistance genes, likely promoted by transduction. Interestingly, we find that Gardnerella species drove this higher genetic diversity, particularly during the first half of the pregnancy. We further present evidence that Gardnerella spp. underwent more frequent recombination and stronger purifying selection in genes involved in lipid metabolism. Overall, our population genetics analyses reveal associations between the vaginal microbiome and PTB and suggest that evolutionary processes acting on vaginal microbes may play a role in adverse pregnancy outcomes such as PTB.

Characteristics of vaginal microbes and classification of the vaginal microbiome.

Background: The vaginal microbiome (VMB) has been classified into several discrete community state types, some of which have been associated with adverse human health conditions. However, the roles of the many vaginal bacteria in modulating the VMB and health remain unclear. Methods: The associations among the vaginal taxa and other vaginal taxa, the vaginal pH, and the host gene expression responses were determined by calculating the correlation among the relative abundance of the vaginal taxa, the association between the vaginal pH and the predominant taxon in the VMB, and the correlation between the relative abundance of the vaginal taxa and human gene expression at the transcriptional level, respectively. Using these associations, an alternative more informative method, the biological vagitype (BVT), is proposed to classify community state types of the VMB. Findings: Most Lactobacillus spp., with the exception of Lactobacillus iners , show significant correlations with host gene expression profiles and negative associations with dysbiosis-associated vaginal taxa. Many non- Lactobacillus spp. exhibit varied correlations with Lactobacillus spp., the vaginal pH, and host gene expression. Compared to other dysbiotic taxa, including Candidatus Lachnocurva vaginae, Gardnerella vaginalis has a stronger positive correlation with vaginal pH and a stronger negative correlation with Lactobacillus spp. Most dysbiosis-associated taxa are associated with stress responses of the host at the transcriptional level, but the genus Mycoplasma has a uniquely strong positive correlation with host immune responses. The association between BVTs of the VMBs and host characteristics, e.g., race/ethnicity, microbial infection, smoking, antibiotics, high blood pressure, economic state, diet, and others, was examined. The BVT classification method improved overall performance in associating specific vaginal microbial populations with host characteristics and phenotypes. Interpretation: This study sheds light on the biological characteristics of the vaginal microbiota, including some less abundant or still unculturable taxa. Since the BVT method was established based on these biological characteristics, the classification outcome of the VMB may have more clinical relevance. Because the BVT method performs better in associating specific vaginal community types with diseases, e.g., bacterial vaginosis and gonorrhea, it could be beneficial for the predictive modeling of adverse health. Funding: This work was supported by grants [UH3AI083263, U54HD080784, and R01HD092415] from the National Institutes of Health; and support from the [GAPPS BMGF PPB] grant from the Global Alliance to Prevent Prematurity and Stillbirth. We would also like to thank the Office of Research on Women's Health at NIH for their generous support. Research in context: Evidence before this study: The vaginal microbiome (VMB) refers to the community of microorganisms in the female lower reproductive tract. The VMB is often a simple ecosystem dominated by a single species. The most predominant bacteria in the VMB include several Lactobacillus species and two non- Lactobacillus species, i.e., Candidatus Lachnocurva vaginae and Gardnerella vaginalis. Lactobacillus species produce lactic acid to lower the vaginal pH and inhibit the growth of disease-associated bacteria. Thus, the predominance of protective Lactobacilli, i.e., L. crispatus, L. jensenii , and L. gasseri , in the VMB is associated with overall vaginal health. However, the role of L. iners in promoting a healthy vaginal ecosystem is less clear. Actually, the biological and health relevance of many bacteria in the female lower reproductive tract is largely unknown. Some bacteria have low relative abundances, e.g., Peptostreptococcus and Coriobacteriaceae spp.; and others are not yet culturable, e.g., Candidatus Lachnocurva vaginae and BVAB TM7. When abundance of a taxon is low, its association with a host characteristic is a challenge. Previous methods to classify the VMB were based simply on their microbial compositions, and the biological characteristics of the vaginal bacteria were largely ignored. Thus, classification of these VMBs into biologically relevant community types, as described herein, should be helpful in determining their relevance to women's reproductive health. Added value of this study: This study examines three biological characteristics of bacteria in the VMB, i.e., the associations among different bacterial taxa, the vaginal pH, and the host response. Based on these three characteristics, the influence of these bacteria, particularly low abundant and unculturable bacteria, on vaginal health is evaluated. L. iners seems to be neutral in maintaining overall vaginal health. Gardnerella vaginalis is apparently more easily inhibited by Lactobacillus spp. than Candidatus Lachnocurva vaginae because of its stronger positive correlation with vaginal pH and negative correlation with Lactobacillus . The genus of Mycoplasma has a unique positive correlation with local immune responses, implying a role for Mycoplasma in promoting inflammation. Compared with previous methods to classify the VMB, a new method, considering the above three biological characteristics of bacteria in the VMB, has been established. The new method performs better in associating specific vaginal communities with host characteristics and phenotypes; e.g., bacterial vaginosis and gonorrhea. Implications of all the available evidence: Accurate biological classification of the VMB is fundamental for assessing its impact on women's health. Our classification scheme represents a step further toward that correct classification, eventually leading to new strategies for clinical assessment of the potential use of the VMB to diagnose or predict women's reproductive health.

Allogeneic haematopoietic cell transplants as dynamical systems: influence of early-term immune milieu on long-term T-cell recovery.

Objectives: Immune recovery following haematopoietic cell transplantation (HCT) functions as a dynamical system. Reducing the duration of intense immune suppression and augmenting antigen presentation has the potential to optimise T-cell reconstitution, potentially influencing long-term outcomes. Methods: Based on donor-derived T-cell recovery, 26 patients were adaptively randomised between mycophenolate mofetil (MMF) administered for 30-day post-transplant with filgrastim for cytokine support (MMF30 arm, N = 11), or MMF given for 15 days with sargramostim (MMF15 arm, N = 15). All patients underwent in vivo T-cell depletion with 5.1 mg kg-1 antithymocyte globulin (administered over 3 days, Day -9 through to Day -7) and received reduced intensity 450 cGy total body irradiation (3 fractions on Day -1 and Day 0). Patients underwent HLA-matched related and unrelated donor haematopoietic cell transplantation (HCT). Results: Clinical outcomes were equivalent between the two groups. The MMF15 arm demonstrated superior T-cell, as well as T-cell subset recovery and a trend towards superior T-cell receptor (TCR) diversity in the first month with this difference persisting through the first year. T-cell repertoire recovery was more rapid and sustained, as well as more diverse in the MMF15 arm. Conclusion: The long-term superior immune recovery in the MMF15 arm, administered GMCSF, is consistent with a disproportionate impact of early interventions in HCT. Modifying the 'immune-milieu' following allogeneic HCT is feasible and may influence long-term T-cell recovery.

Vaginal Microbiome Metagenome Inference Accuracy: Differential Measurement Error according to Community Composition.

Several studies have compared metagenome inference performance in different human body sites; however, none specifically reported on the vaginal microbiome. Findings from other body sites cannot easily be generalized to the vaginal microbiome due to unique features of vaginal microbial ecology, and investigators seeking to use metagenome inference in vaginal microbiome research are "flying blind" with respect to potential bias these methods may introduce into analyses. We compared the performance of PICRUSt2 and Tax4Fun2 using paired 16S rRNA gene amplicon sequencing and whole-metagenome sequencing data from vaginal samples from 72 pregnant individuals enrolled in the Pregnancy, Infection, and Nutrition (PIN) cohort. Participants were selected from those with known birth outcomes and adequate 16S rRNA gene amplicon sequencing data in a case-control design. Cases experienced early preterm birth (<32 weeks of gestation), and controls experienced term birth (37 to 41 weeks of gestation). PICRUSt2 and Tax4Fun2 performed modestly overall (median Spearman correlation coefficients between observed and predicted KEGG ortholog [KO] relative abundances of 0.20 and 0.22, respectively). Both methods performed best among Lactobacillus crispatus-dominated vaginal microbiotas (median Spearman correlation coefficients of 0.24 and 0.25, respectively) and worst among Lactobacillus iners-dominated microbiotas (median Spearman correlation coefficients of 0.06 and 0.11, respectively). The same pattern was observed when evaluating correlations between univariable hypothesis test P values generated with observed and predicted metagenome data. Differential metagenome inference performance across vaginal microbiota community types can be considered differential measurement error, which often causes differential misclassification. As such, metagenome inference will introduce hard-to-predict bias (toward or away from the null) in vaginal microbiome research. IMPORTANCE Compared to taxonomic composition, the functional potential within a bacterial community is more relevant to establishing mechanistic understandings and causal relationships between the microbiome and health outcomes. Metagenome inference attempts to bridge the gap between 16S rRNA gene amplicon sequencing and whole-metagenome sequencing by predicting a microbiome's gene content based on its taxonomic composition and annotated genome sequences of its members. Metagenome inference methods have been evaluated primarily among gut samples, where they appear to perform fairly well. Here, we show that metagenome inference performance is markedly worse for the vaginal microbiome and that performance varies across common vaginal microbiome community types. Because these community types are associated with sexual and reproductive outcomes, differential metagenome inference performance will bias vaginal microbiome studies, obscuring relationships of interest. Results from such studies should be interpreted with substantial caution and the understanding that they may over- or underestimate associations with metagenome content.

Does the Vaginal Microbiome Operate Differently by Race to Influence Risk of Precervical Cancer?

Background: The vaginal microbiome (VMB) plays an important role in the persistence of human papillomavirus (HPV) infection and differs by race and among women with cervical intraepithelial neoplasia (CIN). Materials and Methods: We explored these relationships using 16S rRNA VMB taxonomic profiles of 3050 predominantly Black women. VMB profiles were assigned to three subgroups based on taxonomic markers indicative of vaginal wellness: optimal (Lactobacillus crispatus, L. gasseri, and L. jensenii), moderate (L. iners), and suboptimal (Gardnerella vaginalis, Atopobium vaginae, Ca. Lachnocurva vaginae, and others). Multivariable Firth logistic regression models were adjusted for age, smoking, VMB, HPV, and pregnancy status. Results: VMB prevalence by subgroup was 18%, 30%, and 51% for the optimal, moderate, and suboptimal groups, respectively. In fully adjusted models, the risk of CIN grade 3 (CIN3) among non-Latina (nL) Blacks was twice that of nL Whites (odds ratio [OR] = 2.0, 95% confidence interval [CI]: 1.1, 3.9, p = 0.02). The VMB modified this association (p = 0.04) such that the risk of CIN3 was significantly higher for nL Blacks than for nL Whites only among women with optimal VMBs (OR = 7.8, 95% CI: 1.7, 74.5, p = 0.007). Within racial groups, the risk of CIN3 was only elevated among nL White women with suboptimal VMBs (OR = 6.0, 95% CI: 1.3, 56.9, p = 0.02) compared with their racial counterparts with optimal VMBs. Conclusions: Our findings suggest that race is a modifier of the VMB in HPV carcinogenesis. An optimal VMB does not appear to be protective for nL Black women compared with nL White women.

The influence of maternal factors on the neonatal microbiome and health.

The human microbiome plays an essential role in human health. However, the influence of maternal factors on the neonatal microbiome remains obscure. Herein, our observations suggest that the neonatal buccal microbiome is similar to the maternal buccal microbiome, but the neonatal gastrointestinal microbiome develops a unique composition at an early stage. The low complexity of the neonatal buccal microbiome is a hallmark of maternal and neonatal health, but that of the neonatal gastrointestinal microbiome is associated with maternal inflammation-related metabolites. Microbial infections in the maternal reproductive tract universally impact the complexity of the neonatal microbiomes, and the body site is most important in modulating the composition of the neonatal microbiomes. Additionally, maternal lipids attenuated the adverse influence of several maternal factors on the neonatal microbiomes. Finally, admission of neonates to the newborn intensive care unit is associated with sub-optimal states of the maternal buccal and rectal microbiomes and maternal health.

Microdiversity of the Vaginal Microbiome is Associated with Preterm Birth.

Preterm birth (PTB) is the leading cause of neonatal morbidity and mortality. The vaginal microbiome has been associated with PTB, yet the mechanisms underlying this association are not fully understood. Understanding microbial genetic adaptations to selective pressures, especially those related to the host, may yield new insights into these associations. To this end, we analyzed metagenomic data from 705 vaginal samples collected longitudinally during pregnancy from 40 women who delivered preterm spontaneously and 135 term controls from the Multi-Omic Microbiome Study-Pregnancy Initiative (MOMS-PI). We find that the vaginal microbiome of pregnancies that ended preterm exhibits unique genetic profiles. It is more genetically diverse at the species level, a result which we validate in an additional cohort, and harbors a higher richness and diversity of antimicrobial resistance genes, likely promoted by transduction. Interestingly, we find that Gardnerella species, a group of central vaginal pathobionts, are driving this higher genetic diversity, particularly during the first half of the pregnancy. We further present evidence that Gardnerella spp. undergoes more frequent recombination and stronger purifying selection in genes involved in lipid metabolism. Overall, our results reveal novel associations between the vaginal microbiome and PTB using population genetics analyses, and suggest that evolutionary processes acting on the vaginal microbiome may play a vital role in adverse pregnancy outcomes such as preterm birth.

Dietary Protein and Fiber Affect Gut Microbiome and Treg/Th17 Commitment in Chronic Kidney Disease Mice.

BACKGROUND: Patients with chronic kidney disease (CKD) have dysbiosis, dysmetabolism, and immune dysregulation. Gut microbiome plays an important role shaping the immune system which is an important modulator of CKD progression. METHODS: We compared the effect of a diet low in protein and high in fiber (LP-HF; n = 7) to that of diet rich in protein, but low in fiber (HP-LF; n = 7) on gut microbiome and T-cell commitment in male CKD (Alb/TGF-ß1) mice. The gut microbiomes of these mice were subjected to 16S rRNA taxonomic profiling at baseline, 6 weeks and 12 weeks of the study. RESULTS: The LP-HF diet was associated with an increase in Butyricicoccus pullicaecorum BT, a taxon whose functions include those closely related to butyric acid synthesis (Kendall's W statistic = 180 in analysis of microbiome composition). HP-LF diet was associated with increased abundance of two predominantly proteolytic bacterial strains related to Parabacteroides distasonis (W statistic = 173), Mucispirillum schaedleri, and Bacteroides dorei (W statistic = 192). Pathway analysis suggested that the LP-HF diet induced carbohydrate, lipid, and butyrate metabolism. As compared with HP-LF mice, LP-HF mice had 1.7-fold increase in CD4+Foxp3+Treg cells in spleen and 2.4-fold increase of these cells in peripheral blood. There was an 87% decrease in percentage of CD4+ Th17 + cells in spleen and an 85% decrease in peripheral blood, respectively, in LP-HF mice compared to the HP-LF mice. CONCLUSION: The LP-HF diet promotes the proliferation of saccharolytic bacteria and favors T-cell commitment toward Treg cells in a CKD mouse of model. Clinical significance of the finding needs to be further investigated.

Group Testing Matrix Design for PCR Screening with Real-Valued Measurements.

Single-step nonadaptive group testing approaches for reducing the number of tests required to detect a small subset of positive samples from a larger set require solving two algorithmic problems. First, how to design the samples-to-tests measurement matrix, and second, how to decode the results of the tests to uncover positive samples. In this study, we focus on the first challenge. We introduce real-valued group testing, which matches the characteristics of existing PCR testing pipelines more closely than combinatorial group testing or compressed sensing settings. We show a set of conditions that allow measurement matrices to guarantee unambiguous decoding of positives in this new setting. For small matrix sizes, we also propose an algorithm for constructing matrices that meet the proposed condition. On simulated data sets, we show that the matrices resulting from the algorithm can successfully recover positive samples at higher positivity rates than matrices designed for combinatorial group testing setting. We use wet laboratory experiments involving SARS-CoV-2 nasopharyngeal swab samples to further validate the approach.

Roles of the Microbiota of the Female Reproductive Tract in Gynecological and Reproductive Health.

The microbiome of the female reproductive tract defies the convention that high biodiversity is a hallmark of an optimal ecosystem. Although not universally true, a homogeneous vaginal microbiome composed of species of Lactobacillus is generally associated with health, whereas vaginal microbiomes consisting of other taxa are generally associated with dysbiosis and a higher risk of disease. The past decade has seen a rapid advancement in our understanding of these unique biosystems. Of particular interest, substantial effort has been devoted to deciphering how members of the microbiome of the female reproductive tract impact pregnancy, with a focus on adverse outcomes, including but not limited to preterm birth. Herein, we review recent research efforts that are revealing the mechanisms by which these microorganisms of the female reproductive tract influence gynecologic and reproductive health of the female reproductive tract.

Race, the Vaginal Microbiome, and Spontaneous Preterm Birth.

Previous studies have investigated the associations between the vaginal microbiome and preterm birth, with the aim of determining whether differences in community patterns meaningfully alter risk and could therefore be the target of intervention. We report on vaginal microbial analysis of a nested case-control subset of the Pregnancy, Infection, and Nutrition (PIN) Study, including 464 White women (375 term birth and 89 spontaneous preterm birth, sPTB) and 360 Black women (276 term birth and 84 sPTB). We found that the microbiome of Black women has higher alpha-diversity, higher abundance of Lactobacillus iners, and lower abundance of Lactobacillus crispatus. However, among women who douche, there were no significant differences in microbiome by race. The sPTB-associated microbiome exhibited a lower abundance of L. crispatus, while alpha diversity and L. iners were not significantly associated with sPTB. For each order of magnitude increase in the normalized relative abundance of L. crispatus, multivariable adjusted odds of sPTB decreased by approximately 20% (odds ratio, 0.81; 95% confidence interval, 0.70, 0.94). When we considered the impact of douching, associations between the microbiome and sPTB were limited to women who do not douche. We also observed strong intercorrelations between a range of maternal factors, including poverty, education, marital status, age, douching, and race, with microbiome effect sizes in the range of 1.8 to 5.2% in univariate models. Therefore, race may simply be a proxy for other socially driven factors that differentiate microbiome community structures. Future work will continue to refine reliable microbial biomarkers for preterm birth across diverse cohorts. IMPORTANCE Approximately 10% of all pregnancies in the United States end in preterm birth, and over 14% of pregnancies end in preterm birth among Black women. Knowledge on the associations between vaginal microbiome and preterm birth is important for understanding the potential cause and assessing risk of preterm birth. Our study is one of the largest studies performed to date to investigate the associations between vaginal microbiome and spontaneous preterm birth (sPTB), with stratified design for Black and White women. We found that the vaginal microbiome was different between Black and White women. The vaginal microbiome was associated with sPTB, and a lower abundance of L. crispatus increased the risk of sPTB independent of racial differences in microbial community structures. Furthermore, we also found that vaginal douching obscured the associations between vaginal microbiome, race, and preterm birth, suggesting that vaginal douching is an important factor to consider in future studies.

Genital inflammatory status and the innate immune response to contraceptive initiation.

PROBLEM: Data on the effects of contraceptives on female genital tract (FGT) immune mediators are inconsistent, possibly in part due to pre-existing conditions that influence immune mediator changes in response to contraceptive initiation. METHODS: This study included 161 South African women randomised to injectable depot medroxyprogesterone acetate (DMPA-IM), copper intrauterine device (IUD), or levonorgestrel (LNG) implant in the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial. We measured thirteen cytokines and antimicrobial peptides previously associated with HIV acquisition in vaginal swabs using Luminex and ELISA, before, and at 1 and 3 months after contraceptive initiation. Women were grouped according to an overall baseline inflammatory profile. We evaluated modification of the relationships between contraceptives and immune mediators by baseline inflammation, demographic, and clinical factors. RESULTS: Overall, LNG implant and copper IUD initiation were associated with increases in inflammatory cytokines, while no changes were observed following DMPA-IM initiation. However, when stratifying by baseline inflammatory profile, women with low baseline inflammation in all groups experienced significant increases in inflammatory cytokines, while those with a high baseline inflammatory profile experienced no change or decreases in inflammatory cytokines. CONCLUSION: We conclude that pre-contraceptive initiation immune profile modifies the effect of contraceptives on the FGT innate immune response.

Is prenatal diet associated with the composition of the vaginal microbiome?

BACKGROUND: The vaginal microbiome has been associated with adverse pregnancy outcomes, but information on the impact of diet on microbiome composition is largely unexamined. OBJECTIVE: To estimate the association between prenatal diet and vaginal microbiota composition overall and by race. METHODS: We leveraged a racially diverse prenatal cohort of North Carolina women enrolled between 1995 and 2001 to conduct this analysis using cross-sectional data. Women completed food frequency questionnaires about diet in the previous 3 months and foods were categorised into subgroups: fruits, vegetables, nuts/seeds, whole grains, low-fat dairy, sweetened beverages and red meat. We additionally assessed dietary vitamin D, fibre and yogurt consumption. Stored vaginal swabs collected in mid-pregnancy were sequenced using 16S taxonomic profiling. Women were categorised into three groups based on predominance of species: Lactobacillus iners, Lactobacillus miscellaneous and Bacterial Vaginosis (BV)-associated bacteria. Adjusted Poisson models with robust variance estimators were run to assess the risk of being in a specific vagitype compared to the referent. Race-stratified models (Black/White) were also run. RESULTS: In this study of 634 women, higher consumption of dairy was associated with increased likelihood of membership in the L. crispatus group compared to the L. iners group in a dose-dependent manner (risk ratio quartile 4 vs. 1: 2.01, 95% confidence interval 1.36, 2.95). Increased intake of fruit, vitamin D, fibre and yogurt was also associated with increased likelihood of membership in L. crispatus compared to L. iners, but only among black women. Statistical heterogeneity was only detected for fibre intake. There were no detected associations between any other food groups or risk of membership in the BV group. CONCLUSIONS: Higher consumption of low-fat dairy was associated with increased likelihood of membership in a beneficial vagitype, potentially driven by probiotics.

Airway microbiome dynamics and relationship to ventilator-associated infection in intubated pediatric patients.

BACKGROUND: Little is known about the airway microbiome in intubated mechanically ventilated children. We sought to characterize the airway microbiome longitudinally and in association with clinical variables and possible ventilator-associated infection (VAI). METHODS: Serial tracheal aspirate samples were prospectively obtained from mechanically ventilated subjects under 3 years old from eight pediatric intensive care units in the United States from June 2017 to July 2018. Changes in the tracheal microbiome were analyzed by sequencing bacterial 16S ribosomal RNA gene relative to subject demographics, diagnoses, clinical parameters, outcomes, antibiotic treatment, and the Ventilator-Associated InfectioN (VAIN) score. RESULTS: A total of 221 samples from 58 patients were processed and 197 samples met the >1000 reads criteria (89%), with an average of 43,000 reads per sample. The median number of samples per subject was 3 (interquartile range [IQR]: 2-5), with a median VAIN score of 2 (IQR: 1-3). Proteobacteria was the highest observed phyla throughout the intubation period, followed by Firmicutes and Actinobacteria. Alpha diversity was negatively associated with days of intubation (p = .032) and VAIN score (p = .016). High VAIN scores were associated with a decrease of Mycobacterium obuense, and an increase of Streptococcus peroris, Porphyromonadaceae family (unclassified species), Veillonella atypica, and several other taxa. No specific pattern of microbiome composition related to clinically diagnosed VAIs was observed. CONCLUSIONS: Our data demonstrate decreasing alpha diversity with increasing VAIN score and days of intubation. No specific microbiome pattern was associated with clinically diagnosed VAI.

Unique roles of vaginal Megasphaera phylotypes in reproductive health.

The composition of the human vaginal microbiome has been extensively studied and is known to influence reproductive health. However, the functional roles of individual taxa and their contributions to negative health outcomes have yet to be well characterized. Here, we examine two vaginal bacterial taxa grouped within the genus Megasphaera that have been previously associated with bacterial vaginosis (BV) and pregnancy complications. Phylogenetic analyses support the classification of these taxa as two distinct species. These two phylotypes, Megasphaera phylotype 1 (MP1) and Megasphaera phylotype 2 (MP2), differ in genomic structure and metabolic potential, suggestive of differential roles within the vaginal environment. Further, these vaginal taxa show evidence of genome reduction and changes in DNA base composition, which may be common features of host dependence and/or adaptation to the vaginal environment. In a cohort of 3870 women, we observed that MP1 has a stronger positive association with bacterial vaginosis whereas MP2 was positively associated with trichomoniasis. MP1, in contrast to MP2 and other common BV-associated organisms, was not significantly excluded in pregnancy. In a cohort of 52 pregnant women, MP1 was both present and transcriptionally active in 75.4 % of vaginal samples. Conversely, MP2 was largely absent in the pregnant cohort. This study provides insight into the evolutionary history, genomic potential and predicted functional role of two clinically relevant vaginal microbial taxa.

Vaginal microbiome Lactobacillus crispatus is heritable among European American women.

The diversity and dominant bacterial taxa in the vagina are reported to be influenced by multiple intrinsic and extrinsic factors, including but not limited to pregnancy, contraceptive use, pathogenic states, socioeconomic status, and ancestry. However, the extent to which host genetic factors influence variation in the vaginal microbiota is unclear. We used a biometrical genetic approach to determine whether host genetic factors contribute to inter-individual differences in taxa from a sample of 332 twins who self-identified as being of African (44 pairs) or European ancestry (122 pairs). Lactobacillus crispatus, a major determinant of vaginal health, was identified as heritable among European American women (narrow-sense heritability = 34.7%, P-value = 0.018). Heritability of L. crispatus is consistent with the reduced prevalence of adverse reproductive disorders, including bacterial vaginosis and preterm birth, among women of European ancestry.

Endosymbiont Capture, a Repeated Process of Endosymbiont Transfer with Replacement in Trypanosomatids Angomonas spp.

Trypanosomatids of the subfamily Strigomonadinae bear permanent intracellular bacterial symbionts acquired by the common ancestor of these flagellates. However, the cospeciation pattern inherent to such relationships was revealed to be broken upon the description of Angomonas ambiguus, which is sister to A. desouzai, but bears an endosymbiont genetically close to that of A. deanei. Based on phylogenetic inferences, it was proposed that the bacterium from A. deanei had been horizontally transferred to A. ambiguus. Here, we sequenced the bacterial genomes from two A. ambiguus isolates, including a new one from Papua New Guinea, and compared them with the published genome of the A. deanei endosymbiont, revealing differences below the interspecific level. Our phylogenetic analyses confirmed that the endosymbionts of A. ambiguus were obtained from A. deanei and, in addition, demonstrated that this occurred more than once. We propose that coinfection of the same blowfly host and the phylogenetic relatedness of the trypanosomatids facilitate such transitions, whereas the drastic difference in the occurrence of the two trypanosomatid species determines the observed direction of this process. This phenomenon is analogous to organelle (mitochondrion/plastid) capture described in multicellular organisms and, thereafter, we name it endosymbiont capture.