Background. We sought to describe the temporal relationship between vaginal microbiota and human papillomavirus (HPV) detection. Methods. Thirty-two reproductive-age women self-collected midvaginal ...swabs twice weekly for 16 weeks (937 samples). Vaginal bacterial communities were characterized by pyrosequencing of barcoded 16S rRNA genes and clustered into 6 community state types (CSTs). Each swab was tested for 37 HPV types. The effects of CSTs on the rate of transition between HPV-negative and HPV-positive states were assessed using continuous-time Markov models. Results. Participants had an average of 29 samples, with HPV point prevalence between 58%-77%. CST was associated with changes in HPV status (P<.001). Lactobacillus gassen-dominated CSTs had the fastest HPV remission rate, and a low Lactobacillus community with high proportions of the genera Atopobium (CST IV-B) had the slowest rate compared to L. crispat ws-dominated CSTs (adjusted transition rate ratio aTRR, 4.43, 95% confidence interval CI, 1.11-17.7; aTRR, 0.33, 95% CI, .12-1.19, respectively). The rate ratio of incident HPV for low Lactobacillus CST IV-Awas 1.86 (95% CI, .52-6.74). Conclusions. Vaginal microbiota dominated by L. gasseri was associated with increased clearance of detectable HPV. Frequent longitudinal sampling is necessary for evaluation of the association between HPV detection and dynamic microbiota.
Cervical human papillomavirus (HPV) infection may increase HIV risk. Since other genital infections enhance HIV susceptibility by inducing inflammation, we assessed the impact of HPV infection and ...clearance on genital immunology and the cervico-vaginal microbiome. Genital samples were collected from 65 women for HPV testing, immune studies and microbiota assessment; repeat HPV testing was performed after 6 months. All participants were HIV-uninfected and free of bacterial STIs. Cytobrush-derived T cell and dendritic cell subsets were assessed by multiparameter flow cytometry. Undiluted cervico-vaginal secretions were used to determine cytokine levels by multiplex ELISA, and to assess bacterial community composition and structure by 16S rRNA gene sequence analysis. Neither HPV infection nor clearance were associated with broad differences in cervical T cell subsets or cytokines, although HPV clearance was associated with increased Langerhans cells and HPV infection with elevated IP-10 and MIG. Individuals with HPV more frequently had a high diversity cervico-vaginal microbiome (community state type IV) and were less likely to have an L. gasseri predominant microbiome. In summary, HPV infection and/or subsequent clearance was not associated with inflammation or altered cervical T cell subsets, but associations with increased Langerhans cells and the composition of the vaginal microbiome warrant further exploration.
Background. Genital inflammation is a key determinant of human immunodeficiency virus (HIV) transmission, and may increase HIV-susceptible target cells and alter epithelial integrity. Several genital ...conditions that increase HIV risk are more prevalent in African, Caribbean, and other black (ACB) women, including bacterial vaginosis and herpes simplex virus type-2 (HSV-2) infection. Therefore, we assessed the impact of the genital microbiota on mucosal immunology in ACB women and microbiome-HSV-2 interactions. Methods. Cervicovaginal secretions and endocervical cells were collected by cytobrush and Instead Softcup, respectively. T cells and dendritic cells were assessed by flow cytometry, cytokines by multiplex enzyme-linked immunosorbent assay (ELISA), and the microbiota by 16S ribosomal ribonucleic acid gene sequencing. Results. The cervicovaginal microbiota of 51 participants were composed of community state types (CSTs) showing diversity (20/51; 39%) or predominated by Lactobacillus iners (22/51; 42%), L. crispatus (7/51; 14%), or L. gasseri (2/51; 4%). High-diversity CSTs and specific bacterial phyla (Gardnerella vaginalis and Prevotella bivia) were strongly associated with cervicovaginal inflammatory cytokines, but not with altered endocervical immune cells. However, cervical CD4+ T-cell number was associated with HSV-2 infection and a distinct cytokine profile. Conclusions. This suggests that the genital microbiota and HSV-2 infection may influence HIV susceptibility through independent biological mechanisms.
In this study, we evaluated the association between high-risk human papillomavirus (hrHPV) and the vaginal microbiome. Participants were recruited in Nigeria between April and August 2012. Vaginal ...bacterial composition was characterized by deep sequencing of barcoded 16S rRNA gene fragments (V4) on Illumina MiSeq and HPV was identified using the Roche Linear Array® HPV genotyping test. We used exact logistic regression models to evaluate the association between community state types (CSTs) of vaginal microbiota and hrHPV infection, weighted UniFrac distances to compare the vaginal microbiota of individuals with prevalent hrHPV to those without prevalent hrHPV infection, and the Linear Discriminant Analysis effect size (LEfSe) algorithm to characterize bacteria associated with prevalent hrHPV infection. We observed four CSTs: CST IV-B with a low relative abundance of Lactobacillus spp. in 50% of participants; CST III (dominated by L. iners) in 39·2%; CST I (dominated by L. crispatus) in 7·9%; and CST VI (dominated by proteobacteria) in 2·9% of participants. LEfSe analysis suggested an association between prevalent hrHPV infection and a decreased abundance of Lactobacillus sp. with increased abundance of anaerobes particularly of the genera Prevotella and Leptotrichia in HIV-negative women (P < 0·05). These results are hypothesis generating and further studies are required.
Elucidating the factors that impinge on the stability of bacterial communities in the vagina may help in predicting the risk of diseases that affect women's health. Here, we describe the temporal ...dynamics of the composition of vaginal bacterial communities in 32 reproductive-age women over a 16-week period. The analysis revealed the dynamics of five major classes of bacterial communities and showed that some communities change markedly over short time periods, whereas others are relatively stable. Modeling community stability using new quantitative measures indicates that deviation from stability correlates with time in the menstrual cycle, bacterial community composition, and sexual activity. The women studied are healthy; thus, it appears that neither variation in community composition per se nor higher levels of observed diversity (co-dominance) are necessarily indicative of dysbiosis.
By using information from an assembly of a genome, a new program called AutoEditor significantly improves base calling accuracy over that achieved by previous algorithms. This in turn improves the ...overall accuracy of genome sequences and facilitates the use of these sequences for polymorphism discovery. We describe the algorithm and its application in a large set of recent genome sequencing projects. The number of erroneous base calls in these projects was reduced by 80%. In an analysis of over one million corrections, we found that AutoEditor made just one error per 8828 corrections. By substantially increasing the accuracy of base calling, AutoEditor can dramatically accelerate the process of finishing genomes, which involves closing all gaps and ensuring minimum quality standards for the final sequence. It also greatly improves our ability to discover single nucleotide polymorphisms (SNPs) between closely related strains and isolates of the same species.
Topical microbicides are being explored as an HIV prevention method for individuals who practice receptive anal intercourse. In vivo studies of these microbicides are critical to confirm safety. ...Here, we evaluated the impact of a rectal microbicide containing the antiviral lectin, Griffithsin (GRFT), on the rectal mucosal proteome and microbiome. Using a randomized, crossover placebo-controlled design, six rhesus macaques received applications of hydroxyethylcellulose (HEC)- or carbopol-formulated 0.1% GRFT gels. Rectal mucosal samples were then evaluated by label-free tandem MS/MS and 16 S rRNA gene amplicon sequencing, for proteomics and microbiome analyses, respectively. Compared to placebo, GRFT gels were not associated with any significant changes to protein levels at any time point (FDR < 5%), but increased abundances of two common and beneficial microbial taxa after 24 hours were observed in HEC-GRFT gel (p < 2E-09). Compared to baseline, both placebo formulations were associated with alterations to proteins involved in proteolysis, activation of the immune response and inflammation after 2 hours (p < 0.0001), and increases in beneficial Faecalibacterium spp. after 24 hours in HEC placebo gel (p = 4.21E-15). This study supports the safety profile of 0.1% GRFT gel as an anti-HIV microbicide and demonstrates that current placebo formulations may associate with changes to rectal proteome and microbiota.
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