Impact of Dapivirine and Placebo Vaginal Rings on the Microbiota of Adolescent, Lactating, and Postmenopausal Females

Background A 25 mg dapivirine vaginal ring has been demonstrated to reduce risk of HIV acquisition in nonpregnant adult women. In this secondary analysis of studies conducted in US adolescent, lactating, and postmenopausal females, vaginal microbiota was assessed prior to and after ring use, and between dapivirine and placebo ring users. Methods Vaginal fluid swabs were collected before and after product use for the evaluation of microbiota using Nugent’s criteria, quantitative culture, and qPCR. Results Vaginal ring use did not impact bacterial vaginosis prevalence among the three populations and was associated with minimal shifts in microbiota. Adolescents in both arms demonstrated an increased prevalence of Lactobacillus crispatus and a decrease in quantity of Megasphaera lornae. Postmenopausal active and placebo ring users demonstrated an increased prevalence of lactobacilli and non-albicans yeast while dapivirine ring users demonstrated an increased prevalence of Candida albicans, and increased quantity of Group B Streptococcus (GBS) and non-albicans yeasts. Prevotella species were increased in lactating women while P. timonensis increased in prevalence and concentration among adolescent and postmenopausal women and P. bivia increased in prevalence among adolescent dapivirine ring users. Conclusions Dapivirine vaginal ring use was associated with minimal changes in the vaginal microbiota that are likely not clinically significant.

Vaginal Microbiota, Genital Inflammation and Extracellular Matrix Remodelling Collagenase: MMP-9 in Pregnant Women With HIV, a Potential Preterm Birth Mechanism Warranting Further Exploration

BackgroundPregnant women living with HIV infection (PWLWH) have elevated rates of preterm birth (PTB) in which HIV and cART are implicated. PWLWH also have a high prevalence of adverse vaginal microbiota, which associate with genital tract inflammation. The mechanism underlying PTB in PWLWH is unknown. We present the first data in PWLWH on genital-tract matrix-metalloproteinase-9(MMP-9), an important collagenase implicated in labour onset, and tissue inhibitor of metalloproteinases-1(TIMP-1) and explore correlations with local inflammation and vaginal bacteria.Material and MethodsCervical vaginal fluid (CVF) collected by a soft cup and high vaginal swabs (HVS) were obtained from PWLWH and HIV uninfected pregnant women (HUPW) at three antenatal time points. Maternal characteristics, combination antiretroviral therapy (cART) exposure, and pregnancy outcome were recorded. Concentrations of MMP-9, TIMP-1 and ten cytokines were measured by immunoassays. Vaginal microbiota composition was determined through 16S rRNA amplicon sequencing. MMP-9, TIMP-1 and cytokine concentrations were compared by HIV status, cART, and prematurity and in PWLWH correlations with polymorphonuclear leucocytes, cytokines and bacterial genera were explored.ResultsCVF was available for 50 PWLWH (108 samples) and 12 HUPW (20 samples) between gestation weeks 14-38. Thirty-six PWLWH conceived on cART and 14 initiated post-conception. There were five and one PTB outcomes in PWLWH and HUPW respectively. PWLWH had higher mean CVF concentrations of MMP-9 (p<0.001) and TIMP-1 (p=0.035) in the second trimester compared with HUPW with a similar trend in the third trimester. PWLWH also had higher CVF values of cytokines: IL-1β, IL-8, IL-12 and TNF-α in both trimesters compared to HUPW (p ≤ 0.003). In PWLWH, MMP-9 positively correlated with TIMP-1 (r=0.31, p=0.002) and CVF polymorphonuclear leucocytes (r=0.57, p=0.02). Correlations were observed between MMP-9 and three cytokines: IL-1β (r=0.61), IL-8 (r=0.57) and TNF-α (r=0.64), p<0.001, similarly for TIMP-1. Abundance of anaerobic pathobionts correlated with MMP-9: Gardnerella (r=0.44, p<0.001), Atopobium (r=0.33, p=0.005), and Prevotella genera (r=0.39, p<0.001). Conversely proportion of Lactobacillus genera negatively correlated with MMP-9 (rho=-0.46, p<0.001). MMP-9/TIMP-1 ratio increased with gestational age at sampling in PWLWH, but this was no longer significant after adjusting for confounders and no difference by prematurity was observed in this sub-study.ConclusionsHere we show strong correlations of MMP-9 to genital tract inflammation and sub-optimal bacterial genera in PWLWH indicating the ascending genital tract infection pathway may be a contributory mechanism to the high risk of PTB.

Maternal Vaginal Fluids Play A Major Role In The Colonization of The Neonatal Intestinal Microbiota

Background: Caesarean delivery (CD) is associated with newborns’ health risks due to the blocking of microbiome transfer. To understand the vertical bacterial seeding and reduce CD disadvantages, microbiome transmissions via anal and genital routes were investigated, and the efficiency of vaginal fluid swabbing treatment was evaluated using 16s rDNA sequencing-based techniques.Results: Pregnant women were recruited in the Women and Children’s Hospital, School of Medicine, Xiamen University from June 1st to August 15th, 2017. Maternal faeces (n = 26), maternal vaginal fluids (n = 26), and neonatal transitional stools (n = 26) were collected, while the participants underwent natural delivery (ND) (n = 6), CD (n = 4) and CD with vaginal fluid swabbing (CS) on their newborns (n = 16). 26 mothers with the median age 26.50 (25.00-27.25) years showed no substantial clinical differences. The newborns’ gut microbiota altered among ND, CD and CS, and clustered into two groups (PERMANOVA P < 0.01) of swabbing and no-swabbing exposure. Gut colonization of ND babies majorly originated from maternal vaginal microbes (PERMANOVA P = 0.08), no vertical transmission was observed via anal route in any group. The vaginal transfer partially occurred by swabbing, in which the phyla Firmicutes and Proteobacteria and the genera Lactobacillus, Bacteroides, and Escherichia-Shigella in newborns were similar to their mothers. The recovered taxa predicted KEGG functions of biosynthesis, metabolism, and DNA replication and repair with benefits of low risks of digestive, cardiovascular, and immune diseases.Conclusions: The newborn’s gut microbiota is mainly shaped by maternal vaginal microbiota, and aberrant colonization initiated by CD is partly mitigated by the swabbing treatment.

Vaginal delivery of clotrimazole by mucoadhesion for treatment of candidiasis

The aim of this study was to prepare mucoadhesive vaginal tablets of clotrimazole for treatment of vaginal candidiasis. A combination of mucoadhesive polymers like HPMC K100M, Sodium CMC, and Eudragit L100 were used in different ratios prepare solid dispersions to enhance its solubility. Tablets were prepared by the wet granulation method. Solid dispersions were evaluated for saturation solubility. All tablet batches were evaluated for weight variation, hardness, friability, drug content, swelling index, in vitro drug release study, ex vivo diffusion and mucoadhesive strength. FTIR spectra showed there was no interaction between the drug and the excipients. HPMC K100 M increased the solubility of clotrimazole in simulated vaginal fluid at pH 4.5. Eudragit L100 was shown to increase the swelling and mucoadhesive strength of the tablet, i.e., 3.03 and 3.29 g. The in vitro and ex vivo release of all 9 batches showed between 61 to 78% release in 8h. Ex vivo diffusion studies using sheep vaginal membrane showed 43 to 59% in 6h in simulated vaginal fluid. The release and flux were nearly comparable to marketed tablet i.e., Candid-V6. The drug release of all batches followed the Korsmeyer-Peppas kinetic model, and the mechanism was found to be non‐Fickian/anomalous. Keywords: Clotrimazole, solid dispersion, HPMC K100M, Eudragit L100, Sodium CMC.

Design and Optimization of Novel Vaginal Microsphere Gel of Clotrimazole

The objective of the study was to develop and evaluate sustained release microsphere gel for the drug clotrimazole to be administered through the vaginal route. The effect of polymer ethylcellulose and carbopol 934 on entrapment efficiency and diffusion behavior were investigated respectively. A 32 full-factorial design was used to optimize the formulation of Microsphere gel. Microspheres were characterized by SEM, FTIR, Entrapment efficiency, and particle size. Gels were evaluated for in-vitro drug release in simulated vaginal fluid. The microsphere loaded with clotrimazole in bioadhesive carbopol gel formulation was evaluated for various physicochemical studies and was found to be satisfactory. The rheological profile shows the gel formation at desired condition. It is evaluated for spreadability, drug content, In-vitro drug diffusion, stability study, and bioadhesive study. It may be concluded that spray drying is a suitable method for microsphere preparation and microsphere gel can be used as a novel drug delivery system to prolonge release of clotrimazole for vaginal candidiasis.

Optimization of Streptococcus agalactiae Biofilm Culture in a Continuous Flow System for Photoinactivation Studies

Streptococcus agalactiae is a relevant cause of neonatal mortality. It can be transferred to infants via the vaginal tract and cause meningitis, pneumonia, arthritis, or sepsis, among other diseases. The cause of therapy ineffectiveness and infection recurrence is the growth of bacteria as biofilms. To date, several research teams have attempted to find a suitable medium for the cultivation of S. agalactiae biofilms. Among others, simulated vaginal fluid has been used; however, biofilm production in this medium has been found to be lower than that in tryptic soy broth. We have previously shown that S. agalactiae can be successfully eradicated by photoinactivation in planktonic culture, but there have been no studies on biofilms. The aim of this study was to optimize S. agalactiae biofilm culture conditions to be used in photoinactivation studies. We compared biofilm production by four strains representing the most common serotypes in four different broth media with crystal violet staining. Then, we evaluated stationary biofilm culture in microtiter plates and biofilm growth in a CDC Biofilm Reactor® (BioSurface Technologies, Bozeman, MT, USA) under continuous flow conditions. Subsequently, we applied Rose Bengal-mediated photoinactivation to both biofilm models. We have shown that photoinactivation is efficient in biofilm eradication and is not cyto/phototoxic to human keratinocytes. We found conditions allowing for stable and repetitive S. agalactiae biofilm growth in continuous flow conditions, which can be successfully utilized in photoinactivation assays and potentially in all other antibacterial studies.

The Potential of Metabolomic Analyses as Predictive Biomarkers of Preterm Delivery: A Systematic Review

Scopeas the leading cause of perinatal mortality and morbidity worldwide, the impact of premature delivery is undisputable. Thus far, non-invasive, cost-efficient and accurate biochemical markers to predict preterm delivery are scarce. The aim of this systematic review is to investigate the potential of non-invasive metabolomic biomarkers for the prediction of preterm delivery.Methods and ResultsDatabases were systematically searched from March 2019 up to May 2020 resulting in 4062 articles, of which 45 were retrieved for full-text assessment. The resulting metabolites used for further analyses, such as ferritin, prostaglandin and different vitamins were obtained from different human anatomical compartments or sources (vaginal fluid, serum, urine and umbilical cord) and compared between groups of women with preterm and term delivery. None of the reported metabolites showed uniform results, however, a combination of metabolomics biomarkers may have potential to predict preterm delivery and need to be evaluated in future studies.