A non-invasive method to sample immune cells in the lower female genital tract using menstrual discs

T cells in the human female genital tract (FGT) 2 are key mediators of susceptibility to and protection from infection, including HIV and other sexually transmitted infections. There is a critical need for increased understanding of the distribution and activation of T cell populations in the FGT, but current sampling methods require a healthcare provider and are expensive, limiting the ability to study these populations longitudinally. To address these challenges, we have developed a method to sample immune cells from the FGT utilizing disposable menstrual discs which are non-invasive, self-applied, and low-cost. To demonstrate reproducibility, we sampled the cervicovaginal fluid (CVF) 3 of healthy, reproductive-aged individuals using menstrual discs over three sequential days. CVF was processed for cervicovaginal cells, and high parameter flow cytometry was used to characterize immune populations. We identified large numbers of live, CD45+ leukocytes, as well as distinct populations of T cells and B cells. Within the T cell compartment, activation and suppression status of T cell subsets were consistent with previous studies of the FGT utilizing current approaches, including identification of both tissue resident and migratory populations. In addition, the T cell population structure was highly conserved across days within individuals but divergent across individuals. Our approach to sample immune cells in the FGT with menstrual discs will decrease barriers to participation and empower longitudinal sampling in future research studies.

A Noninvasive Method to Sample Immune Cells in the Lower Female Genital Tract Using Menstrual Discs

T cells in the human female genital tract (FGT) are key mediators of susceptibility to and protection from infection, including HIV and other sexually transmitted infections. There is a critical need for increased understanding of the distribution and activation of T cell populations in the FGT, but current sampling methods require a healthcare provider and are expensive, limiting the ability to study these populations longitudinally. To address these challenges, we have developed a method to sample immune cells from the FGT utilizing disposable menstrual discs which are noninvasive, self-applied, and low in cost. To demonstrate reproducibility, we sampled the cervicovaginal fluid of healthy, reproductive-aged individuals using menstrual discs across 3 sequential days. Cervicovaginal fluid was processed for cervicovaginal cells, and high-parameter flow cytometry was used to characterize immune populations. We identified large numbers of live, CD45+ leukocytes, as well as distinct populations of T cells and B cells. Within the T cell compartment, activation and suppression status of T cell subsets were consistent with previous studies of the FGT utilizing current approaches, including identification of both tissue-resident and migratory populations. In addition, the T cell population structure was highly conserved across days within individuals but divergent across individuals. Our approach to sample immune cells in the FGT with menstrual discs will decrease barriers to participation and empower longitudinal sampling in future research studies.

Update on the Impact of Depot Medroxyprogesterone Acetate on Vaginal Mucosal Endpoints and Relevance to Sexually Transmitted Infections

PURPOSE OF REVIEW

The long-acting reversible intramuscularly-injected contraceptive depot medroxyprogesterone acetate (DMPA-IM) is widely used by cisgender women in Africa. Although DMPA-IM provides reliable contraception, potential effects on the female genital tract (FGT) mucosa have raised concern, including risk of HIV infection. This review summarises and compares evidence from observational cohort studies and the randomised Evidence for Contraceptive Options in HIV Outcomes (ECHO) Trial.

RECENT FINDINGS

Although previous observational studies found women using DMPA-IM had higher abundance of bacterial vaginosis (BV)-associated bacteria, increased inflammation, increased cervicovaginal HIV target cell density, and epithelial barrier damage, sub-studies of the ECHO Trial found no adverse changes in vaginal microbiome, inflammation, proteome, transcriptome, and risk of viral and bacterial STIs, other than an increase in Th17-like cells. Randomised data suggest that DMPA-IM use does not adversely change mucosal endpoints associated with acquisition of infections. These findings support the safe use of DMPA-IM in women at high risk of acquiring STIs, including HIV.

Latent tuberculosis is associated with heightened levels of pro-and anti-inflammatory cytokines among Kenyan men and women living with HIV on long-term antiretroviral therapy

BACKGROUND

Persons with HIV (PWH) on antiretroviral therapy (ART) have persistent immune activation associated with increased risk for non-AIDS related diseases. Latent tuberculosis infection (LTBI), endemic in Africa, may contribute to this immune dysregulation. We evaluated the impact of HIV and TB co-infection on plasma pro- and anti-inflammatory cytokines among Kenyan adults.

METHODS

We compared data from 221 PWH on long-term ART and 177 HIV-negative adults examining biomarkers of pro-[sCD14, interleukin (IL)-2, IL-6, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), IL-12p70, IL-17A] and anti(IL-4, IL-5, IL-13) inflammatory cytokines, by HIV/LTBI status (HIV+LTBI+, HIV+LTBI-, HIV-LTBI+, HIV-LTBI-). LTBI was diagnosed based on a positive QuantiFERON TB Gold-Plus test in the absence of active TB symptoms. Linear regression was used to evaluate the associations of HIV, LTBI, and HIV/LTBI status with biomarkers adjusting for clinical factors including HIV-specific factors.

RESULTS

Half of the participants were women and 52% had LTBI. HIV was independently associated with higher sCD14, IL-15, IL-6, IL-4, IL-5. LTBI was independently associated with higher TNF-α, IL-12p70, IL-17A, IL-4, IL-13 in adjusted models ( P  < 0.05). LTBI status was associated with higher IL-4 and IL-12p70 only among PWH, but not HIV-negative participants ( P  < 0.05 for interactions). In multivariate analysis, only HIV+LTBI+ demonstrated elevated levels of TNF-α, IL-6, IL-12p70, IL-15, IL-17A, IL4, IL-5, IL-13 in comparison to the HIV-LTBI- ( P  < 0.05 for all). The effect of LTBI on cytokines among PWH was independent of CD4 + T-cell count and ART duration.

CONCLUSIONS

Despite viral suppression, persons with HIV and LTBI exhibit abnormal cytokine production accompanied by high concentrations of pro- and anti-inflammatory cytokines.

Copper intrauterine device increases vaginal concentrations of inflammatory anaerobes and depletes lactobacilli compared to hormonal options in a randomized trial

Effective contraceptives are a global health imperative for reproductive-aged women. However, there remains a lack of rigorous data regarding the effects of contraceptive options on vaginal bacteria and inflammation. Among 218 women enrolled into a substudy of the ECHO Trial (NCT02550067), we evaluate the effect of injectable intramuscular depot medroxyprogesterone acetate (DMPA-IM), levonorgestrel implant (LNG), and a copper intrauterine device (Cu-IUD) on the vaginal environment after one and six consecutive months of use, using 16S rRNA gene sequencing and multiplex cytokine assays. Primary endpoints include incident BV occurrence, bacterial diversity, and bacterial and cytokine concentrations. Secondary endpoints are bacterial and cytokine concentrations associated with later HIV seroconversion. Participants randomized to Cu-IUD exhibit elevated bacterial diversity, increased cytokine concentrations, and decreased relative abundance of lactobacilli after one and six months of use, relative to enrollment and other contraceptive options. Total bacterial loads of women using Cu-IUD increase 5.5 fold after six months, predominantly driven by increases in the concentrations of several inflammatory anaerobes. Furthermore, growth of L. crispatus (MV-1A-US) is inhibited by Cu2+ ions below biologically relevant concentrations, in vitro. Our work illustrates deleterious effects on the vaginal environment induced by Cu-IUD initiation, which may adversely impact sexual and reproductive health.

Lactic acid from vaginal microbiota enhances cervicovaginal epithelial barrier integrity by promoting tight junction protein expression

BACKGROUND

Women with a cervicovaginal microbiota dominated by Lactobacillus spp. are at reduced risk of acquiring sexually transmitted infections including HIV, but the biological mechanisms involved remain poorly defined. Here, we performed metaproteomics on vaginal swab samples from young South African women (n = 113) and transcriptomics analysis of cervicovaginal epithelial cell cultures to examine the ability of lactic acid, a metabolite produced by cervicovaginal lactobacilli, to modulate genital epithelial barrier function.

RESULTS

Compared to women with Lactobacillus-depleted microbiota, women dominated by vaginal lactobacilli exhibit higher abundance of bacterial lactate dehydrogenase, a key enzyme responsible for lactic acid production, which is independently associated with an increased abundance of epithelial barrier proteins. Physiological concentrations of lactic acid enhance epithelial cell culture barrier integrity and increase intercellular junctional molecule expression.

CONCLUSIONS

These findings reveal a novel ability of vaginal lactic acid to enhance genital epithelial barrier integrity that may help prevent invasion by sexually transmitted pathogens. Video abstract.

Initiating Intramuscular Depot Medroxyprogesterone Acetate Increases Frequencies of Th17-like Human Immunodeficiency Virus Target Cells in the Genital Tract of Women in South Africa: A Randomized Trial

BACKGROUND

Cervicovaginal CD4+ T cells are preferential targets for human immunodeficiency virus (HIV) infection and have consequently been used as a proxy measure for HIV susceptibility. The ECHO randomized trial offered a unique opportunity to consider the association between contraceptives and Th17-like cells within a trial designed to evaluate HIV risk. In a mucosal substudy of the ECHO trial, we compared the impact of initiating intramuscular depot medroxyprogesterone acetate (DMPA-IM), copper-IUD, and the levonorgestrel (LNG) implant on cervical T cells.

METHODS

Cervical cytobrushes from 58 women enrolled in the ECHO trial were collected at baseline and 1 month after contraceptive initiation. We phenotyped cervical T cells using multiparameter flow cytometry, characterized the vaginal microbiome using 16s sequencing, and determined proteomic signatures associated with Th17-like cells using mass spectrometry.

RESULTS

Unlike the LNG implant or copper-IUD, DMPA-IM was associated with higher frequencies of cervical Th17-like cells within 1 month of initiation (P = .012), including a highly susceptible, activated population co-expressing CD38, CCR5, and α4β7 (P = .003). After 1 month, women using DMPA-IM also had more Th17-like cells than women using the Cu-IUD (P = .0002) or LNG implant (P = .04). Importantly, in women using DMPA-IM, proteomic signatures signifying enhanced mucosal barrier function were associated with the increased abundance of Th17-like cells. We also found that a non-Lactobacillus-dominant microbiome at baseline was associated with more Th17-like cells post-DMPA-IM (P = .03), although this did not influence barrier function.

CONCLUSIONS

Our data suggest that DMPA-IM-driven accumulation of HIV-susceptible Th17-like cells might be counteracted by their role in maintaining mucosal barrier integrity.

CLINICAL TRIALS REGISTRATION

NCT02550067.

HIV Prevention in a Time of COVID-19: A Report from the HIVR4P // Virtual Conference 2021

The HIV Research for Prevention (HIVR4P) conference catalyzes knowledge sharing on biomedical HIV prevention interventions such as HIV vaccines, antibody infusions, pre-exposure prophylaxis, and microbicides in totality-from the molecular details and delivery formulations to the behavioral, social, and structural underpinnings. HIVR4P // Virtual was held over the course of 2 weeks on January 27-28 and February 3-4, 2021 as the coronavirus disease 2019 (COVID-19) pandemic continued to inflict unprecedented harm globally. The HIVR4P community came together with 1,802 researchers, care providers, policymakers, implementers, and advocates from 92 countries whose expertise spanned the breadth of the HIV prevention pipeline from preclinical to implementation. The program included 113 oral and 266 poster presentations. This article presents a brief summary of the conference highlights. Complete abstracts, webcasts, and daily rapporteur summaries may be found on the conference website (https://www.hivr4p.org/).

Persistent, Asymptomatic Colonization with Candida is Associated with Elevated Frequencies of Highly Activated Cervical Th17-Like Cells and Related Cytokines in the Reproductive Tract of South African Adolescents

Cervicovaginal inflammation, nonoptimal microbiota, T-cell activation, and hormonal contraceptives may increase HIV risk, yet associations between these factors and subclinical Candida colonization or hyphae are unknown. We collected cervicovaginal samples from 94 South African adolescents, aged 15 to 19 years, who were randomized to injectable norethisterone enanthate (Net-En), an etonorgesterol/ethinyl estradiol vaginal ring (NuvaRing), or oral contraceptives in the UChoose trial (NCT02404038) at baseline and 16 weeks post-randomization. We assessed cervicovaginal samples for subclinical Candida colonization (by quantitative PCR [qPCR]), hyphae (by Gram stain), microbiota composition (by 16S rRNA gene sequencing), cytokine concentrations (by Luminex), and cervical T-cell phenotypes and activation (by multiparameter flow cytometry). While hormonal contraceptive type did not influence incidence of Candida colonization or hyphae, hyphae presence was associated with significantly elevated concentrations of IL-22, IL-17A and IL-17F, all produced by Th17 cells, but not of other cytokines, such as IL-1β or IL-6, after adjustment for confounders. Subclinical Candida colonization was associated with reduced frequencies of Th17-like cells and elevated frequencies of CCR6-CCR10 T cells. Women with Candida hyphae were less likely to have bacterial vaginosis (BV). Persistent, subclinical colonization with Candida over 16 weeks was associated with significant increases in Th17-related cytokine concentrations and highly activated Th17-like and CCR6-CCR10 T-cell frequencies. These data suggest that vaginal Candida colonization and hyphae increase Th17-related cytokines, but not overall female genital tract inflammation in Sub-Saharan African adolescents. Persistent Candida colonization, even when asymptomatic, may increase Th17 cell frequencies and related cytokines and thereby could subsequently increase HIV risk, although the causal relationship requires confirmation. IMPORTANCE Sub-Saharan African female adolescents are globally at the highest risk of HIV acquisition, and genital inflammation, microbial dysbiosis, and cervical HIV target cell activation are thought to contribute to this risk. Previously, the relationship between these mucosal factors and subclinical vaginal Candida colonization or hyphae has not been described, and the role of HIV-susceptible Th17 cells in mediating anti-Candida immunity in the human female genital tract has not been clearly established. We show that presence of yeast hyphae was associated with increases in Th17 cell-related cytokines and the absence of microbial dysbiosis, and that persistent Candida colonization resulted in significant increases in Th17-related cytokines and highly activated Th17-like cell frequencies. Our results suggest that Th17 cells are important for anti-Candida immunity in the human female genital tract and that prolonged vaginal Candida colonization may contribute to increased HIV risk in Sub-Saharan African adolescents by increasing HIV target cell frequencies and activation.

The Effect Of Contraception On Genital Cytokines In Women Randomized To Copper Intrauterine Device, Intramuscular Depot Medroxyprogesterone Acetate Or Levonorgestrel Implant

BACKGROUND

The ECHO Trial randomized women to intramuscular depot medroxyprogesterone acetate (DMPA-IM), levonorgestrel implant (LNG-implant), or copper intrauterine device (Cu-IUD). In a sub-study of the ECHO Trial, we tested the hypothesis that contraceptives influence genital inflammation by comparing cervicovaginal cytokine changes following contraception initiation. In addition, we compared cytokine profiles in women who acquired HIV (cases) versus those remaining HIV-negative (controls).

METHODS

Women (n=251) from South Africa and Kenya were included. Twenty-seven cervicovaginal cytokines were measured by Luminex at baseline, 1- and 6-month post-contraceptive initiation. In addition, cytokines were measured pre-seroconversion in HIV cases (n=25) and controls (n=100).

RESULTS

At 6-months post-contraceptive initiation, women using Cu-IUD had increased concentrations of 25/27 cytokines compared to their respective baseline concentrations. In contrast, women initiating DMPA-IM and LNG-implant did not experience changes in cervicovaginal cytokines. Pre-seroconversion concentrations of IL-1β, IL-6, and TNF-α, previously associated with HIV risk, correlated with increased HIV risk in a logistic regression analysis, although not significantly after correcting for multiple comparisons. Adjusting for contraceptive arm did not alter these results.

CONCLUSION

Although Cu-IUD use broadly increased cervicovaginal cytokine concentrations at 6-months post-insertion, these inflammatory changes were found not to be a significant driver of HIV risk.

Comparison of Female Genital Tract Cytokine and Microbiota Signatures Induced by Initiation of Intramuscular DMPA and NET-EN Hormonal Contraceptives - a Prospective Cohort Analysis

Background

Cervicovaginal inflammation, bacterial microbiota and hormonal contraceptives all influence sexual and reproductive health. To date, the effects of intramuscular depo-medroxyprogesterone acetate (DMPA-IM) versus injectable norethisterone enanthate (NET-EN) on vaginal microbiota or cytokines have not been compared back-to-back, although in-vitro data suggest that DMPA-IM and NET-EN have different pharmacokinetic and biologic activities. This study aimed at comparing the effects of DMPA-IM versus NET-EN initiation on cervicovaginal cytokines and microbiota in women at high risk for sexually transmitted infections (STIs) assigned to the respective contraceptives.

Methods

We collected socio-demographic characteristics and vaginal samples from women initiating DMPA-IM (ECHO Trial; n = 53) and NET-EN (UChoose Trial; n = 44) at baseline and after two consecutive injections to assess cytokine concentrations by Luminex, vaginal microbiota by 16S rRNA gene sequencing, STIs, bacterial vaginosis (BV) and candidiasis.

Results

Cytokine concentrations did not change significantly after initiating DMPA-IM or NET-EN, although NET-EN versus DMPA-IM-associated profiles were distinct. While the abundance of bacterial taxa associated with optimal and non-optimal microbiota fluctuated with DMPA-IM use, overall community composition did not significantly change with either contraceptive. HSV-2 serology, chlamydial infection, gonorrhoea and candidiasis did not influence the associations between contraceptive type and cervicovaginal cytokines or microbiota.

Conclusions

Both DMPA-IM and NET-EN use did not lead to broad inflammatory or microbiota changes in the female genital tract of sub-Saharan African women. This suggests that NET-EN is likely a viable option for contraception in African women at high risk of BV and STIs.

The Complex Link between the Female Genital Microbiota, Genital Infections, and Inflammation

The female genital tract microbiota is part of a complex ecosystem influenced by several physiological, genetic, and behavioral factors. It is uniquely linked to a woman's mucosal immunity and plays a critical role in the regulation of genital inflammation. A vaginal microbiota characterized by a high abundance of lactobacilli and low overall bacterial diversity is associated with lower inflammation. On the other hand, a more diverse microbiota is linked to high mucosal inflammation levels, a compromised genital epithelial barrier, and an increased risk of sexually transmitted infections and other conditions. Several bacterial taxa such as Gardnerella spp., Prevotella spp., Sneathia spp., and Atopobium spp. are well known to have adverse effects; however, the definitive cause of this microbial dysbiosis is yet to be fully elucidated. The aim of this review is to discuss the multiple ways in which the microbiota influences the overall genital inflammatory milieu and to explore the causes and consequences of this inflammatory response. While there is abundant evidence linking a diverse genital microbiota to elevated inflammation, understanding the risk factors and mechanisms through which it affects genital health is essential. A robust appreciation of these factors is important for identifying effective prevention and treatment strategies.

Pandemic-Related Instructor Talk: How New Instructors Supported Students at the Onset of the COVID-19 Pandemic

At the same time that COVID-19 cases in the United States first began to increase, fellows in a mentored teaching apprenticeship for postdoctoral scientists began to teach undergraduate seminars. The fellows suddenly needed to support students emotionally and switch to online instruction. They were encouraged to acknowledge and address the pandemic during each class and decided to do so. In this case study, we examined the language fellows used in response to this encouragement, hypothesizing that they would engage in a variety of pandemic-related instructor talk, i.e., language that instructors use in the classroom that is not directly tied to educational content. We analyzed transcripts from 17 2-hour undergraduate biology seminar courses and found 167 instances of pandemic-related instructor talk. We used grounded theory to identify categories that emerged from these quotations: Positive coping mechanisms and self-care; Adjusting to online learning; Compassionate instruction; Personal impacts; COVID-19 and society; Dreaming; and Biology of COVID-19. Talk in these categories may help build relationships among instructors and students. The category about quickly Adjusting to online learning is unique, in that it is unlikely that there will be another time that will require simultaneous and rapid national movement to online instruction. In addition, four of the seven categories are direct consequences of COVID-19 specifically, and thus are unique to this time. Analyzing pandemic-related instructor talk has shed light on how new instructors navigated the trials of teaching in 2020.

Microbial function and genital inflammation in young South African women at high risk of HIV infection

BACKGROUND

Female genital tract (FGT) inflammation is an important risk factor for HIV acquisition. The FGT microbiome is closely associated with inflammatory profile; however, the relative importance of microbial activities has not been established. Since proteins are key elements representing actual microbial functions, this study utilized metaproteomics to evaluate the relationship between FGT microbial function and inflammation in 113 young and adolescent South African women at high risk of HIV infection. Women were grouped as having low, medium, or high FGT inflammation by K-means clustering according to pro-inflammatory cytokine concentrations.

RESULTS

A total of 3186 microbial and human proteins were identified in lateral vaginal wall swabs using liquid chromatography-tandem mass spectrometry, while 94 microbial taxa were included in the taxonomic analysis. Both metaproteomics and 16S rRNA gene sequencing analyses showed increased non-optimal bacteria and decreased lactobacilli in women with FGT inflammatory profiles. However, differences in the predicted relative abundance of most bacteria were observed between 16S rRNA gene sequencing and metaproteomics analyses. Bacterial protein functional annotations (gene ontology) predicted inflammatory cytokine profiles more accurately than bacterial relative abundance determined by 16S rRNA gene sequence analysis, as well as functional predictions based on 16S rRNA gene sequence data (p < 0.0001). The majority of microbial biological processes were underrepresented in women with high inflammation compared to those with low inflammation, including a Lactobacillus-associated signature of reduced cell wall organization and peptidoglycan biosynthesis. This signature remained associated with high FGT inflammation in a subset of 74 women 9 weeks later, was upheld after adjusting for Lactobacillus relative abundance, and was associated with in vitro inflammatory cytokine responses to Lactobacillus isolates from the same women. Reduced cell wall organization and peptidoglycan biosynthesis were also associated with high FGT inflammation in an independent sample of ten women.

CONCLUSIONS

Both the presence of specific microbial taxa in the FGT and their properties and activities are critical determinants of FGT inflammation. Our findings support those of previous studies suggesting that peptidoglycan is directly immunosuppressive, and identify a possible avenue for biotherapeutic development to reduce inflammation in the FGT. To facilitate further investigations of microbial activities, we have developed the FGT-DB application that is available at http://fgtdb.org/ . Video Abstract.

Initiation of Antiretroviral Therapy Differentially Influences Genital and Systemic Immune Activation in HIV-Infected Women

Antiretroviral therapy (ART) has significantly improved the quality of life of HIV-infected individuals: reducing plasma viremia, restoring CD4⁺ T cell numbers, and correcting imbalances in blood memory T cell subsets. While ART improves immune correlates at mucosal sites, including the lower female genital tract (FGT), ART initiation has been associated with reactivation of common FGT infections. We investigated the effect of ART on immune activation and inflammation in the genital tract. We measured blood and genital T cell activation, proliferation, and immunosenescence (CD38, HLADR, Ki67, CD127, and CD57), and cytokine levels in women on ART for ∼7 years (cross-sectional analysis) or initiating ART (immediately before and 1 month after). Effector memory T cells predominated in blood and FGT during chronic infection, irrespective of ART status. In women initiating ART, 1 month was insufficient for T cell reconstitution, or alterations in T cell subset distribution, despite both plasma and genital viral loads decreasing to undetectable levels in most participants. Initiating ART was accompanied by a decline in plasma IP-10 that correlated with decreased blood CD38 expression in blood (p = .0204) but not in the FGT. The reduction in plasma (but not genital) cytokine levels due to ART initiation was dependent on their concentrations before treatment. While T cell activation decreased significantly in blood (CD4: p = .032; CD8: p = .0137), activation levels remained similar in the genital tract despite 1 month of treatment. Overall, the decrease in cellular activation and inflammation seen in blood with ART initiation was not evident in the FGT.

Exploring potential of vaginal Lactobacillus isolates from South African women for enhancing treatment for bacterial vaginosis

Antibiotics continue to be the standard-of-care for bacterial vaginosis (BV), although recurrence rates are high. Vaginal probiotics may improve durability of BV treatment, although few probiotics for vaginal health contain Lactobacillus spp. that commonly colonize the lower female genital tract. Characteristics of vaginal Lactobacillus strains from South African women were evaluated for their probiotic potential in vitro compared to strains from commercial vaginal products, including growth at varying pHs, ability to lower pH, produce D-/L-lactate and H2O2, influence growth of BV-associated Gardnerella vaginalis and Prevotella bivia, adherence to cervical cells and susceptibility to antibiotics. Fifty-seven Lactobacillus strains were purified from cervico-vaginal fluid, including L. crispatus, L. jensenii, L. gasseri, L. mucosae, and L. vaginalis. L crispatus strains grew better at pHs below 4.5 and lowered pH more effectively than other strains. Production of D-/L-lactate and H2O2 varied between Lactobacillus species and strains. Lactobacillus strains generally inhibited P. bivia more uniformly than G. vaginalis isolates. All vaginal Lactobacillus isolates were resistant to metronidazole while susceptibility to clindamycin varied. Furthermore, vaginal Lactobacillus strains tended to be broadly susceptible to penicillin, amoxicillin, rifampicin and rifabutin. Whole-genome-sequencing of five of the best-performing vaginal Lactobacillus strains confirmed their likely safety, due to antimicrobial resistance elements being largely absent, while putative intact prophages were present in the genomes of two of the five strains. Overall, vaginal Lactobacillus strains largely performed better in these in vitro assays than probiotic strains currently used in probiotics for vaginal health. Including the best-performing vaginal Lactobacillus isolates in a region-specific probiotic for vaginal health may result in improved BV treatment options.

HIV Research for Prevention 2018: From Research to Impact Conference Summary and Highlights

The HIV Research for Prevention (HIVR4P) conference is dedicated to advancing HIV prevention research, responding to a growing consensus that effective and durable prevention will require a combination of approaches as well as unprecedented collaboration among scientists, practitioners, and community workers from different fields and geographic areas. The conference theme in 2018, "From Research to Impact," acknowledged an increasing focus on translation of promising research findings into practical, accessible, and affordable HIV prevention options for those who need them worldwide. HIVR4P 2018 was held in Madrid, Spain, on 21-25 October, with >1,400 participants from 52 countries around the globe, representing all aspects of HIV prevention research and implementation. The program included 137 oral and 610 poster presentations. This article presents a brief summary of highlights from the conference. More detailed information, complete abstracts as well as webcasts and daily Rapporteur summaries may be found on the conference website.

Schistosomiasis Burden and Its Association With Lower Measles Vaccine Responses in School Children From Rural Cameroon

Background and Methods: Schistosomiasis is debilitating and reported to impair immune responsiveness of infected hosts. In Cameroon, mass drug administration (MDA) is used in schoolchildren to reduce transmission of S. haematobium and S. mansoni. The effects of MDA and the impact of schistosomiasis on the titers of antibodies in vaccinated children have been poorly studied. We therefore assessed the prevalence of schistosomiasis in schoolchildren, eight months after MDA, in two locations: Barombi Koto (BK), endemic for S. haematobium (N = 169) and Yoro (Y), endemic for S. mansoni (N = 356). Age, gender, residence time and frequency of contact with river water were assessed as risk factors for infection and morbidity in both localities. In 70 schoolchildren from BK and 83 from Y, ultrasound was used to assess morbidity according to the WHO guidelines. Evaluation of measles antibodies was performed in previously vaccinated schoolchildren (14 with S. haematobium and 12 egg-negative controls from BK and 47 with S. mansoni and12 egg-negative controls from Y).

Principal Findings and conclusions: The prevalence of S. haematobium was 25. 4% in BK (43/169) and 34.8% for S. mansoni in Y (124/356), indicating the persistent transmission of schistosomiasis despite MDA. Older age (AOR 1.31; 95%CI 1.12–1.54) and higher frequencies of exposure to river water (AOR 1.99; 95%CI 1.03–3.86) were identified as risks for infection in BK whereas only older age (OR 1.15; 95%CI 1.04–1.27) was a risk for infection in Y. Bladder pathology (score 2 to 5) was observed in 29.2% (7/24) of egg-positive children in BK and liver pathology (pattern C) in 31.1% (19/61) of egg-positive children in Y. There was a positive correlation between S. haematobium egg burden and bladder pathology (AOR 1.01; 95% CI 0.99–1.02) and positive correlation between S. mansoni-driven liver pathology and female gender (AOR 3.01; 95% CI 0.88–10.26). Anti-measles antibodies in vaccinated children were significantly lower in S. mansoni-infected when compared to egg-negative controls (p = 0.001), which was not observed in the S. haematobium-infected group from BK. Our results demonstrate a questionable efficacy of MDA alone in halting schistosomiasis transmission and confirm a possible immunomodulatory effect of S. mansoni on response to vaccines.

Inflammatory cytokine biomarkers of asymptomatic sexually transmitted infections and vaginal dysbiosis: a multicentre validation study

OBJECTIVES

Vaginal dysbiosis and STIs are important drivers of the HIV epidemic and reproductive complications. These conditions remain prevalent, partly because most cases are asymptomatic. We have shown that inflammatory cytokines interleukin (IL)-1α, IL-1β and interferon-γ-induced protein (IP)-10 are biomarkers for detecting asymptomatic STIs and vaginal dysbiosis (bacterial vaginosis (BV) or intermediate microbiota). This study aimed to validate the performance of these biomarkers in African women recruited regardless of symptoms.

METHODS

IL-1α, IL-1β and IP-10 were measured in menstrual cup secretions, endocervical, lateral vaginal wall and vulvovaginal swabs from 550 women from Pretoria, Soweto and Cape Town, South Africa and Bondo, Kenya using Luminex and ELISA. STIs were assessed by PCR, BV by Nugent scoring and vaginal microbiota by 16S rRNA sequencing.

RESULTS

Across four study populations and four types of genital specimens, the performance of IL-1α, IL-1β and IP-10 for identification of women with STIs, BV or intermediate microbiota was consistent. Of the genital samples assessed, biomarkers measured in lateral vaginal wall swabs performed best, correctly classifying 76%(95% CI 70% to 81%) of women according to STI, BV or intermediate microbiota status (sensitivity 77%, specificity 71%) and were more accurate than clinical symptoms (sensitivity 41%, specificity 57%) (p=0.0003). Women incorrectly classified as STI/BV positive using the biomarkers had more abundant dysbiosis-associated bacteria, including Prevotella bivia and Gardnerella sp, detected by 16S rRNA sequencing, but not Nugent scoring. Including vaginal pH with the cytokine biomarkers improved the accuracy of the test (82% (95% CI 75% to 88%) correctly classified), although pH alone had poor specificity (61%).

CONCLUSIONS

An inexpensive, point-of-care screening test including IL-1α, IL-1β and IP-10 (and potentially pH) could be used in resource-limited settings to identify women with asymptomatic STIs and dysbiosis. These women could then be referred for aetiological testing, followed by specific treatment.

High human papillomavirus (HPV) prevalence in South African adolescents and young women encourages expanded HPV vaccination campaigns

The objectives of the study were to investigate prevalence of cervical human papillomavirus (HPV) genotypes to inform HPV vaccination strategy in South Africa and to study factors associated with HPV prevalence. Sexually active, HIV-negative women, aged 16-22 years recruited from Soweto (n = 143) and Cape Town (n = 148) were tested for cervical HPV and other genital infections. Overall HPV prevalence was 66.7% (194/291) in young women. Cape Town women were more likely to have multiple HPV infections than the Soweto women (48.0%, 71/148 versus 35.0%, 50/143 respectively, p = 0.033) and probable HR-HPV types (34.5%, 51/148 versus 21.7%, 31/143 respectively, p = 0.022). The most frequently detected HPV types were HPV-16 (11.7%), HPV-58 (10.3%), HPV-51 (8.9%), HPV-66 (8.6%), HPV-18 and HPV-81 (7.6% each). HPV types targeted by the bivalent HPV vaccine (HPV-16/18) were detected in 18.6% (54/291) of women, while those in the quadrivalent vaccine (HPV-6/11/16/18) were detected in 24.7% (72/291) of women; and those in the nonavalent vaccine (HPV-6/11/16/18/31/33/45/52/58) were detected in 38.5% (112/291) of women. In a multivariable analysis, bacterial vaginosis remained significantly associated with HPV infection (OR: 4.0, 95% CI: 1.4-12.6). Women were more likely to be HPV positive if they had received treatment for STI during the past 6-months (OR: 3.4, 95% CI: 1.1-12.4) or if they had ever been pregnant (OR: 2.3, 95% CI: 1.1-5.5). Compared to women who reported only one sexual partner, those with increased number of lifetime sex partners were more likely to have HPV (4-10 partners: OR: 2.9, 95% CI: 1.1-8.0). The high prevalence of HPV types targeted by the nonavalent HPV vaccine encourages the introduction of this vaccine and catch-up HPV vaccination campaigns in South Africa. The high burden of BV and concurrent STIs also highlights the need to improve the prevention and appropriate management of sexually-acquired and other genital tract infections in South African youth.

Microbial Composition Predicts Genital Tract Inflammation and Persistent Bacterial Vaginosis in South African Adolescent Females

Young African females are at an increased risk of HIV acquisition, and genital inflammation or the vaginal microbiome may contribute to this risk. We studied these factors in 168 HIV-negative South African adolescent females aged 16 to 22 years. Unsupervised clustering of 16S rRNA gene sequences revealed three clusters (subtypes), one of which was strongly associated with genital inflammation. In a multivariate model, the microbiome compositional subtype and hormonal contraception were significantly associated with genital inflammation. We identified 40 taxa significantly associated with inflammation, including those reported previously (Prevotella, Sneathia, Aerococcus, Fusobacterium, and Gemella) as well as several novel taxa (including increased frequencies of bacterial vaginosis-associated bacterium 1 [BVAB1], BVAB2, BVAB3, Prevotella amnii, Prevotella pallens, Parvimonas micra, Megasphaera, Gardnerella vaginalis, and Atopobium vaginae and decreased frequencies of Lactobacillus reuteri, Lactobacillus crispatus, Lactobacillus jensenii, and Lactobacillus iners). Women with inflammation-associated microbiomes had significantly higher body mass indices and lower levels of endogenous estradiol and luteinizing hormone. Community functional profiling revealed three distinct vaginal microbiome subtypes, one of which was characterized by extreme genital inflammation and persistent bacterial vaginosis (BV); this subtype could be predicted with high specificity and sensitivity based on the Nugent score (≥9) or BVAB1 abundance. We propose that women with this BVAB1-dominated subtype may have chronic genital inflammation due to persistent BV, which may place them at a particularly high risk for HIV infection.

Converging epidemics of sexually transmitted infections and bacterial vaginosis in southern African female adolescents at risk of HIV

Adolescents in Africa are at high risk for HIV infection, other sexually transmitted infections (STIs) and bacterial vaginosis (BV). Since behavior and burden of STIs/BV may influence HIV risk, behavioral risk factors and prevalence of STIs/BV were compared in HIV-seronegative adolescent females (n = 298; 16-22 years) from two South African communities (Soweto and Cape Town). STIs ( Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Mycoplasma genitalium, herpes simplex virus (HSV)-1, HSV-2, Treponema pallidum, and Haemophilus ducreyi) were detected by multiplex polymerase chain reaction, human papillomavirus (HPV) by Roche Linear Array, and BV by Nugent scoring. Rates of BV (Nugent ≥7; 46.6%) and HPV (66.8%) were high in both communities. Prevalence of C. trachomatis and N. gonorrhoeae were >2-fold higher in Cape Town than Soweto (Chlamydia: 42% [62/149] versus 18% [26/148], p < 0.0001; gonorrhoea 11% [17/149] versus 5% [7/148], p = 0.05). Only 24% of adolescents with vaginal discharge-causing STIs or BV were symptomatic. In South African adolescents, clinical symptoms compatible with vaginal discharge syndrome had a sensitivity of 23% and specificity of 85% for the diagnosis of discharge-causing STI or BV. In a region with high HIV prevalence and incidence, >70% of young women with treatable conditions that could enhance HIV risk would have been missed because they lacked symptoms associated with syndromic management.