Vaginal microbiota of asymptomatic bacterial vaginosis and vulvovaginal candidiasis: Are they different from normal microbiota?

Premature rupture of membranes and changes in the vaginal microbiome - Probiotics

Preterm birth affects approximately 15 million women worldwide, of which 30 % is due to preterm premature rupture of membranes (PPROM). The reasons for shortening the duration of pregnancy are seen in genetic, hormonal, immunological and socio-economic conditions. Recent years have provided a lot of evidence on the impact of the microbiota and whole microbiome on pregnant women, suggesting that the microorganisms inhabiting the vagina significantly affect the risk of preterm delivery. The aim of the study was to review studies evaluating the composition of the vaginal microflora and its role in the occurrence of preterm labor caused by PPROM, and to evaluate the potential beneficial effect of probiotics on preventing the development of preterm labor. Vaginal microbial dysbiosis is observed in PPROM, which, due to its association with a high risk of prematurity and infection, increases neonatal morbidity and mortality. Further research on biomarkers for screening, early prognosis and diagnosis of PPROM seems advisable. Probiotics as a potential intervention can prevent the development of pathological vaginal flora, reducing the risk of infection in women planning pregnancy and pregnant women.

Reconstructing the transcriptional regulatory network of probiotic L. reuteri is enabled by transcriptomics and machine learning

Limosilactobacillus reuteri, a probiotic microbe instrumental to human health and sustainable food production, adapts to diverse environmental shifts via dynamic gene expression. We applied the independent component analysis (ICA) to 117 RNA-seq data sets to decode its transcriptional regulatory network (TRN), identifying 35 distinct signals that modulate specific gene sets. Our findings indicate that the ICA provides a qualitative advancement and captures nuanced relationships within gene clusters that other methods may miss. This study uncovers the fundamental properties of L. reuteri's TRN and deepens our understanding of its arginine metabolism and the co-regulation of riboflavin metabolism and fatty acid conversion. It also sheds light on conditions that regulate genes within a specific biosynthetic gene cluster and allows for the speculation of the potential role of isoprenoid biosynthesis in L. reuteri's adaptive response to environmental changes. By integrating transcriptomics and machine learning, we provide a system-level understanding of L. reuteri's response mechanism to environmental fluctuations, thus setting the stage for modeling the probiotic transcriptome for applications in microbial food production.

IMPORTANCE

We have studied Limosilactobacillus reuteri, a beneficial probiotic microbe that plays a significant role in our health and production of sustainable foods, a type of foods that are nutritionally dense and healthier and have low-carbon emissions compared to traditional foods. Similar to how humans adapt their lifestyles to different environments, this microbe adjusts its behavior by modulating the expression of genes. We applied machine learning to analyze large-scale data sets on how these genes behave across diverse conditions. From this, we identified 35 unique patterns demonstrating how L. reuteri adjusts its genes based on 50 unique environmental conditions (such as various sugars, salts, microbial cocultures, human milk, and fruit juice). This research helps us understand better how L. reuteri functions, especially in processes like breaking down certain nutrients and adapting to stressful changes. More importantly, with our findings, we become closer to using this knowledge to improve how we produce more sustainable and healthier foods with the help of microbes.

An Indirect Fluorescence Microscopy Method to Assess Vaginal Lactobacillus Concentrations

Lactobacillus species are the main colonizers of the vaginal microbiota in healthy women. Their absolute quantification by culture-based methods is limited due to their fastidious growth. Flow cytometry can quantify the bacterial concentration of these bacteria but requires the acquisition of expensive equipment. More affordable non-culturable methods, such as fluorescence microscopy, are hampered by the small size of the bacteria. Herein, we developed an indirect fluorescence microscopy method to determine vaginal lactobacilli concentration by determining the correlation between surface area bacterial measurement and initial concentration of an easily cultivable bacterium (Escherichia coli) and applying it to lactobacilli fluorescence microscopy counts. In addition, vaginal lactobacilli were quantified by colony-forming units and flow cytometry in order to compare these results with the indirect method results. The colony-forming-unit values were lower than the results obtained from the other two techniques, while flow cytometry and fluorescence microscopy results agreed. Thus, our developed method was able to accurately quantify vaginal lactobacilli.

Bacterial Vaginosis and Vulvovaginal Candidiasis Pathophysiologic Interrelationship

Among the infectious causes of vulvovaginal symptoms, bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC) dominate. Apart from infrequent mixed infections, both are considered independent and caused by unrelated pathogenic mechanisms. Clinical experience, however, is strongly suggestive that in some populations these infections are linked with recurrent BV (RBV) serving as the dominant etiopathogenic trigger for development of recurrent VVC (RVVC) with profound clinical and therapeutic consequences. The biologic basis for this critical interrelationship is discussed and suggests that as a consequence of BV dysbiosis, and not necessarily because of antibiotics prescribed, immune defenses are compromised, neutralizing vaginal yeast tolerance. The consequent BV-induced vaginal proinflammatory environment predisposes to mixed infection or consecutive episodes of post-treatment VVC. Recurrent BV and repeated antimicrobial drug exposure also predispose to acquired fluconazole resistance in C. albicans isolates, contributing to refractory vulvovaginal candidiasis.

Comparison of databases useful for the analysis of vaginal microbiota in Japanese women using next-generation sequencing data (QIIME 2 software)

AIMS

Approximately 10% of children are born prematurely, and bacterial vaginosis during pregnancy is associated with preterm delivery. Highly accurate species-level vaginal microflora analysis helps control bacteria-induced preterm birth. Therefore, we aimed to conduct a bioinformatic analysis of gene sequences using 16S databases and compare their efficacy in comprehensively identifying potentially pathogenic vaginal microbiota in Japanese women.

METHODS AND RESULTS

The 16 s rRNA databases, Silva, Greengenes, and the basic local alignment search tool (BLAST) were compared to determine whether the classification quality could be improved using the V3-V4 region next-generation sequencing (NGS) sequences. It was found that NGS data were aligned using the BLAST database with the QIIME 2 platform, whose classification quality was higher than that of Silva, and the combined Silva and Greengenes databases based on the mutual complementarity of the two databases.

CONCLUSIONS

The reference database selected during the bioinformatic processing influenced the recognized sequence percentage, taxonomic rankings, and accuracy. This study showed that the BLAST database was the best choice for NGS data analysis of Japanese women's vaginal microbiota.

Vaginal microecology and its role in human papillomavirus infection and human papillomavirus associated cervical lesions

The vaginal microecology comprises the vaginal microbiome, immune microenvironment, vaginal anatomy, and the cervicovaginal fluid, which is rich in metabolites, enzymes, and cytokines. Investigating its role in the female reproductive system holds paramount significance. The advent of next-generation sequencing enabled a more profound investigation into the structure of the vaginal microbial community in relation to the female reproductive system. Human papillomavirus infection is prevalent among women of reproductive age, and persistent oncogenic HPV infection is widely recognized as a factor associated with cervical cancer. Extensive previous research has demonstrated that dysbiosis of vaginal microbiota characterized by a reduction in Lactobacillus species, heightens susceptivity to HPV infection, consequently contributing to persistent HPV infection and the progression of cervical lesion. Likewise, HPV infection can exacerbate dysbiosis. This review aims to provide a comprehensive summary of current literatures and to elucidate potential mechanisms underlying the interaction between vaginal microecology and HPV infection, with the intention of offering valuable insights for future clinical interventions.

Vaginal Microbiota Molecular Profiling in Women with Bacterial Vaginosis: A Novel Diagnostic Tool

Bacterial vaginosis (BV) is a most common microbiological syndrome. Multiplex next-generation sequencing (NGS) or molecular tests allow a complete and accurate vaginal microbiota profiling in order to determine the primary causative agent. Due to the high costs and limited availability of NGS, the multiplex real-time PCR draws more attention. The present study aimed to evaluate the microbial composition and dominant lactobacilli species in non-pregnant women with bacterial vaginosis using a multiplex RT-PCR test and determine its diagnostic significance. In total, 331 women complaining of vaginal discharge were included. BV was confirmed upon clinical examination and Nugent criteria. A real-time PCR test was carried out with a new Femoflor test, which identifies opportunistic bacteria, STD pathogens, and some viruses. According to the results, the rate of lactobacilli is significantly reduced in BV-affected patients when compared to healthy women. Moreover, the rate of L. crispatus significantly decreases, while the rate of L. iners remains high. Among obligate anaerobic bacteria, Gardnerella vaginalis was the most prevalent in women with BV. The Femoflor test demonstrated high sensitivity and specificity for diagnosing BV. Moreover, the test allows the identification of infection in women with intermediate vaginal microbiota, as well as STD pathogens, and viruses. Thus, the application of real-time PCR tests can be effectively used in vaginal microbiota evaluation in women with BV, intermediate vaginal microbiota, and healthy women. In addition, this test may be used as an alternative to the Amsel criteria and Nugent scoring method in diagnosing BV.

Association of Pregnancy and HIV Status With Molecular-Bacterial Vaginosis in Indian Women

BACKGROUND

Bacterial vaginosis (BV) is a highly prevalent disorder of the cervicovaginal microbiota. Molecular-BV may put women at increased risk for adverse reproductive and obstetric outcomes. We investigated the association of HIV and pregnancy on the vaginal microbiota and associations with molecular-BV in women of reproductive age from Pune, India.

SETTING

We studied vaginal samples from N = 170 women, including N = 44 nonpregnant HIV seronegative, N = 56 pregnant seronegative, N = 47 nonpregnant women with HIV (WWH), and N = 23 pregnant WWH, and collected data on clinical, behavioral, and demographic factors.

METHODS

We used 16S rRNA gene amplicon sequencing to characterize the composition of the vaginal microbiota. We classified the vaginal microbiota of these women into community state types based on bacterial composition and relative abundance and further categorized them into molecular-BV versus Lactobacillus -dominated states. To determine associations between pregnancy and HIV status with outcome of molecular-BV, logistic regression models were used.

RESULTS

There was a high prevalence of molecular-BV (30%) in this cohort. We found that pregnancy was associated with decreased odds of molecular-BV (adjusted OR = 0.35, 95% CI: 0.14 to 0.87), while HIV was associated with increased odds of molecular-BV (adjusted OR = 2.76, 95% CI: 1.33 to 5.73), even when controlling for multiple relevant factors such as age, number of sexual partners, condom use, and douching.

CONCLUSION

Larger and longitudinal studies are needed to further characterize molecular-BV and the vaginal microbiota in pregnant women and WWH and relate these factors to infectious, reproductive, and obstetric outcomes. In the long term, these studies may lead to novel microbiota-based therapeutics to improve women's reproductive and obstetric health.

Acetate modulates the inhibitory effect of Lactobacillus gasseri against the pathogenic yeasts Candida albicans and Candida glabrata

The exploration of the interference prompted by commensal bacteria over fungal pathogens is an interesting alternative to develop new therapies. In this work we scrutinized how the presence of the poorly studied vaginal species Lactobacillus gasseri affects relevant pathophysiological traits of Candida albicans and Candida glabrata. L. gasseri was found to form mixed biofilms with C. albicans and C. glabrata resulting in pronounced death of the yeast cells, while bacterial viability was not affected. Reduced viability of the two yeasts was also observed upon co-cultivation with L. gasseri under planktonic conditions. Either in planktonic cultures or in biofilms, the anti-Candida effect of L. gasseri was augmented by acetate in a concentration-dependent manner. During planktonic co-cultivation the two Candida species counteracted the acidification prompted by L. gasseri thus impacting the balance between dissociated and undissociated organic acids. This feature couldn't be phenocopied in single-cultures of L. gasseri resulting in a broth enriched in acetic acid, while in the co-culture the non-toxic acetate prevailed. Altogether the results herein described advance the design of new anti-Candida therapies based on probiotics, in particular, those based on vaginal lactobacilli species, helping to reduce the significant burden that infections caused by Candida have today in human health.

The bacterial communities in vagina of different Candida species-associated vulvovaginal candidiasis

The incidence of vaginal infection caused by Candida species has considerably increased over the past two decades. Candida albicans is the main cause of vulvovaginal candidiasis (VVC); however, non-albicans Candida (NAC) species, such as Candida glabrata and Candida tropicalis, are now frequently identified in VVC patients. Although the vaginal microbiome (VMB) was well studied in Candida albicans-associated VVC patients, the fungal influence on bacterial communities of NAC species-associated VVC and potential microbial interplay contributing to VVC pathology remain elusive. We characterized VMB via Candida albicans and NAC species-associated VVC patients, as Candida albicans (CA, n = 16), Candida glabrata (CG, n = 16), Candida tropicalis (CT, n = 4), and recruiting healthy (CON, n = 20) women as references of dysbiosis and eubiosis. The bacterial diversity of the vagina in the CG group significantly declined. Further, all VVC patients have a higher abundance of Lactobacillus iners, especially for the CG group. Meanwhile, the predicted functions in all VVC are toned which may be associated with a disruption in the bacterial network. In conclusion, according to the taxonomic analysis, we found that the vaginal microbiome in C. glabrata-associated VVC women is different from that of other Candida species-associated VVC women, implying a different pathogenesis.

Comparison of Metagenomic Sequencing and the NanoString nCounter Analysis System for the Characterization of Bacterial and Viral Communities in Vaginal Samples

DNA sequencing assays have been used to characterize the vaginal microbiome and to identify associations with clinical outcomes. The purpose of this study was to evaluate the utility of the NanoString nCounter platform, a more efficient assay compared to sequencing, for the characterization of vaginal microbial communities. A panel of NanoString nCounter probes was designed to detect common vaginal bacteria and viruses with relevance to reproductive health. A defined synthetic community of microbes and 43 clinical samples were interrogated with NanoString nCounter assays and compared to known compositions or metagenomic shotgun sequencing (MSS) results. The NanoString nCounter platform and MSS were able to distinguish closely related microbes. In clinical samples, the relative abundance of bacterial species was similar between the two assays. The assays sometimes disagreed when targets were present at low abundance. More viruses were detected by MSS than by nCounter. However, the nCounter assays are able to provide results in about 30 h with minimal hands-on time, whereas MSS requires at least 138 to 178 h with extensive hands-on time. The reagent cost for the two assays was similar, but the overall cost of the nCounter was lower due to the minimal hands-on time. MSS can be used to inform the design of a targeted multiplex panel for the assessment of vaginal microbial communities, thereby allowing for more cost-effective and rapid screening of patient samples for research studies. The sensitivity for low abundance microbes could be improved, possibly by adding additional target amplification cycles before nCounter assessment. This approach has potential as an assay with both research and clinical applications. IMPORTANCE Metagenomic shotgun sequencing can inform the design of a targeted multiplex panel by which the NanoString nCounter platform can assess vaginal microbial communities, thereby allowing for more cost-effective and rapid screening of patient samples.

Natural progress history of asymptomatic bacterial vaginosis in Chinese Han women and associated risk factors

OBJECTIVE

Asymptomatic bacterial vaginosis (aBV) is prevalent in the general population, while a previous study only investigated the natural history of aBV in women at high-risk. This stage study was to investigate the natural history of aBV in Chinese Han women at general risk and examine risk factors associated with different outcomes.

METHODS

Women of reproductive age with aBV were enrolled and prospectively followed up with for four months. Participants were classified into one of three outcomes: progress, self-cure or no-change. Univariate and multivariate analyses were used to determine the association between potential risk factors and outcomes.

RESULTS

A total of 3420 subjects were screened and 1014 women with aBV were enrolled. Eventually, 984 participants completed the study, with 30 patients dropped out. Among the 984 cases, 42 cases self-cured spontaneously, while 433 cases progressed and 509 cases did not change significantly. Of the 433 cases that progressed, several types of mixed infections were observed in addition to 196 symptomatic bacterial vaginosis. According to univariate analysis, frequent travel (OR, 95% CI, 2.73 [2.09 ~ 3.55]) and history of bacterial vaginosis (BV) (5.47, [4.15 ~ 7.21]) exhibited significant associations with aBV progression, while condom contraception (0.46 [0.36 ~ 0.61]) and lower Nugent score (0.49, [0.37 ~ 0.64]) demonstrated protective effects for self-cure. According to multivariate regression analysis, the risk factors for aBV progression were history of BV (6.67, [4.86 ~ 9.15]) and frequent travel (3.57, 2.59 ~ 4.92). Condom contraception (0.36, 0.26 ~ 0.49) exhibited a protective effect against aBV progression.

CONCLUSION

Without intervention, a large proportion of aBV would progress, compared to the very few patients whose aBV self-cured spontaneously. It is necessary to clinically intervene aBV patients. Condom utilization can be used as an effective method to improve the outcome of aBV.

The role of probiotics in vaginal health

Probiotics have been widely used in the treatment of intestinal diseases, but the effect of probiotics on female reproductive tract health is still controversial. Lactobacillus is the most abundant microorganism in the vagina, which is related to the vaginal mucosal barrier. Lactobacillus adheres to the vaginal epithelium and can competitively antagonize the colonization of pathogens. The factors produced by Lactobacillus, such as bacteriocin and hydrogen peroxide (H₂O₂), can inhibit the growth of pathogenic microorganisms and maintain the low pH environment of the vagina. Probiotics play an important role in maintaining the stability of vaginal microenvironment, improving immune defense and blocking the progression of cervical cancer. We review the research progress of probiotics represented by Lactobacillus in gynecological diseases such as human papilloma virus (HPV) infection, bacterial vaginosis (BV) and Genitourinary Syndrome of Menopause (GSM), so as to provide basis for further exerting the role of probiotics in women’s health.

Metagenomic Shotgun Sequencing of Endocervical, Vaginal, and Rectal Samples among Fijian Women with and without Chlamydia trachomatis Reveals Disparate Microbial Populations and Function across Anatomic Sites: a Pilot Study

Chlamydia trachomatis is a sexually transmitted pathogen and a global public health concern. Little is known about the microbial composition and function across endocervical, vaginal, and rectal microbiomes in the context of C. trachomatis infection. We evaluated the microbiomes of 10 age-matched high-risk Fijian women with and without C. trachomatis using metagenomic shotgun sequencing (MSS). Lactobacillus iners and Lactobacillus crispatus dominated the vagina and endocervix of uninfected women. Species often found in higher relative abundance in bacterial vaginosis (BV)-Mageeibacillus indolicus, Prevotella spp., Sneathia spp., Gardnerella vaginalis, and Veillonellaceae spp.-were dominant in C. trachomatis-infected women. This combination of BV pathogens was unique to Pacific Islanders compared to previously studied groups. The C. trachomatis-infected endocervix had a higher diversity of microbiota and microbial profiles that were somewhat different from those of the vagina. However, community state type III (CST-III) and CST-IV predominated, reflecting pathogenic microbiota regardless of C. trachomatis infection status. Rectal microbiomes were dominated by Prevotella and Bacteroides, although four women had unique microbiomes with Gardnerella, Akkermansia, Bifidobacterium, and Brachyspira. A high level of microbial similarity across microbiomes in two C. trachomatis-infected women suggested intragenitorectal transmission. A number of metabolic pathways in the endocervix, driven by BV pathogens and C. trachomatis to meet nutritional requirements for survival/growth, 5-fold higher than that in the vagina indicated that endocervical microbial functions are likely more diverse and complex than those in the vagina. Our novel findings provide the impetus for larger prospective studies to interrogate microbial/microbiome interactions that promote C. trachomatis infection and better define the unique genitorectal microbiomes of Pacific Islanders. IMPORTANCE Chlamydia trachomatis is the primary cause of bacterial sexually transmitted infections worldwide, with a disturbing increase in annual rates. While there is a plethora of data on healthy and pathogenic vaginal microbiomes-defining microbial profiles and associations with sexually transmitted infections (STIs)-far fewer studies have similarly examined the endocervix or rectum. Further, vulnerable populations, such as Pacific Islanders, remain underrepresented in research. We investigated the microbial composition, structure, and function of these anatomic microbiomes using metagenomic shotgun sequencing among a Fijian cohort. We found, primarily among C. trachomatis-infected women, unique microbial profiles in endocervical, vaginal, and rectal microbiomes with an increased diversity and more complex microbial pathways in endocervical than vaginal microbiomes. Similarities in microbiome composition across sites for some women suggested intragenitorectal transmission. These novel insights into genitorectal microbiomes and their purported function require prospective studies to better define Pacific Islander microbiomes and microbial/microbiome interactions that promote C. trachomatis infection.

Vaginal Dysbiotic Microbiome in Women With No Symptoms of Genital Infections

The vaginal microbiome plays a critical role in determining the progression of female genital tract infections; however, little is known about the vaginal microbiota of Indian women. We aimed to investigate the vaginal microbial architecture of women with asymptomatic bacterial vaginosis (BV) (n=20) and normal microbiota (n=19). Microbial diversity was analyzed in vaginal swabs from regularly menstruating women (18-45yrs) by 16S rRNA V3-V4 amplicon (MiSeq Illumina) sequencing. Rarefaction analysis showed a higher number of species in normal flora compared to BV. Alpha diversity as measured by Pielou’s evenness revealed microbial diversity was significantly greater in BV samples than normal microbiota (p= 0.0165). Beta diversity comparison using UniFrac metrics indicated distinct microbial communities clustering between normal and BV flora. Firmicutes were the major phyla observed in vaginal specimens of normal microbiota whereas Actinobacteria, Fusobacteria, Bacteroidetes were significantly abundant in BV samples. Notably, the relative abundance of Lactobacillus was significantly high in normal microbiota. Conversely Gardnerella, Sneathia, Prevotella, Atopobium, Ureaplasma, Dialister significantly dominated dysbiotic microbiota. Relative frequency of Lactobacillus decreased significantly in BV (6%) as compared to normal microbiota (35.2%). L. fermentum, L. gasseri, L. iners, L. jensenii, L. mucosae, L. ruminis, L. salivarius, L. coleohominis was more exclusively present in normal microbiota. L. iners was detected from both the groups with a relative frequency of 50.4% and 17.2% in normal and BV microbiota respectively. Lefse analysis indicated Atopobium vaginae, Sneathia amnii, Mycoplasma hominis Prevotella disiens in the vaginal microbiota as a biomarker for dysbiosis and L. jensenii as a biomarker of a healthy microbiota. Firmicutes were negatively correlated to Tenericutes, Actinobacteria, Bacteroidetes, and Fusobacteria. Proteobacteria positively correlated to Tenericutes, and Bacteroidetes were shown to be positively correlated to Fusobacteria. Predicted functional analysis indicated differences in the functional profiles between BV and normal microbiota. Normal microbiota utilized pathways essential for phosphatidylglycerol biosynthesis I & II, peptidoglycan biosynthesis, geranylgeranyl diphosphate biosynthesis I, mevalonate pathway, CoA biosynthesis pathway I and pyrimidine nucleotide salvage; whereas BV bacteria had characteristic aromatic amino acid biosynthesis, pentose phosphate pathway, carbohydrate degradation. In conclusion, women with asymptomatic BV have vaginal microbiota significantly different than women with normal microbiota. Furthermore, the study provides insights into the vaginal microbial structure of Indian women that will enable us to explore the prospective candidates for restoring the vaginal microbiota.

Diagnosis of bacterial vaginosis: Comparison of Nugent´s and novel microscopic method

Background/Aim. Bacterial vaginosis (BV) is a common cause of vaginal discomfort in women. The aim of this study was to compare Nugent?s scoring system and novel microscopy method, introduced in our laboratory and used in BV diagnosis. Methods. This study included 705 pregnant and asymptomatic women between 24 and 28 weeks of pregnancy. The degree of agreement between methods was determined by the kappa (?) index. The sensitivity, specificity, positive and negative predictive value of the novel microscopy method was compared to Nugent?s score as standard. Results. Based on the scoring system of both methods, Nugent?s and novel microscopy method, BV was diagnosed in 21% and 25% of women, respectively. Despite the disparities among diagnostic criteria, which mainly concerned classification of intermediary samples, the degree of agreement between categories, determined by ? index, was satisfactory: Nugent?s vs. novel microscopy method (? = 0.68; good agreement), and Nugent?s vs. novel microscopy method without intermediary results (? = 0.83; very good agreement). We also demonstrated that compared to Nugent?s method, as the golden standard, the novel microscopy method had high sensitivity and specificity (ranging from 75%?99.3%) and positive and negative predictive values (ranging from 88.8%?99.5%). Our method is based on a relative number of bacterial morphotypes, either rod forms (? 1.5 ?m, lactobacilli) or non-rod forms (< 1.5 ?m, bacterial vaginosis associated bacteria) under 200? magnification, which extends the surface of examined preparation, but without prolongation of observer?s working time. Conclusion. The novel microscopy method in diagnosing BV corresponded well with Nugent?s scoring system which allows it to be an alternative method in diagnosing BV. Further-more, the novel microscopy method is based on a relative number of bacterial morphotypes that appeared to be flexible and can be reorganized in the way to categorize findings into only two groups: normal and BV, which makes it comparable to dichotomous Amsel?s clinical criterion.

Genomic Analysis of Limosilactobacillus fermentum ATCC 23271, a Potential Probiotic Strain with Anti-Candida Activity

Limosilactobacillus fermentum (ATCC 23271) was originally isolated from the human intestine and has displayed antimicrobial activity, primarily against Candida species. Complete genome sequencing and comparative analyses were performed to elucidate the genetic basis underlying its probiotic potential. The ATCC 23271 genome was found to contain 2,193,335 bp, with 2123 protein-coding sequences. Phylogenetic analysis revealed that the ATCC 23271 strain shares 941 gene clusters with six other probiotic strains of L. fermentum. Putative genes known to confer probiotic properties have been identified in the genome, including genes related to adhesion, tolerance to acidic pH and bile salts, tolerance to oxidative stress, and metabolism and transport of sugars and other compounds. A search for bacteriocin genes revealed a sequence 48% similar to that of enterolysin A, a protein from Enterococcus faecalis. However, in vitro assays confirmed that the strain has inhibitory activity on the growth of Candida species and also interferes with their adhesion to HeLa cells. In silico analyses demonstrated a high probability of the protein with antimicrobial activity. Our data reveal the genome features of L. fermentum ATCC 23271, which may provide insight into its future use given the functional benefits, especially against Candida infections.

Quantitative and specific detection of viable pathogens on a portable microfluidic chip system by combining improved propidium monoazide (PMAxx) and loop-mediated isothermal amplification (LAMP)

An accurate and specific detection of viable Candida albicans (C. albicans) in vaginal discharge is crucial for the diagnosis of vulvovaginal candidiasis (VVC) and assessment of antifungal effects. In this study, improved propidium monoazide (PMAxx) and loop-mediated isothermal amplification (LAMP) were used for the first time to distinguish between viable and dead C. albicans. A portable microfluidic chip system was developed to detect multiple viable pathogens in parallel. The consumption of samples and reagents in per reaction cell were only 0.94 μL, less than 1/25 of the conventional 25 μL Eppendorf tubular test method, both significantly reducing testing cost and greatly simplifying the detection of multiple viable pathogens. The concentration of PMAxx was optimized against C. albicans at 4.0 log CFU mL^-1 to 5.0 log CFU mL^-1, and 1 μM PMAxx was proven to be suitable for the detection of C. albicans in clinical samples. When testing mixtures containing different ratios of viable to dead C. albicans, PMAxx-LAMP could circumvent the signal arising from dead cells and, therefore, reflected the abundance of viable cells precisely. Furthermore, the suitability of this technique to evaluate the effects of antifungal agents, including clotrimazole, miconazole, and tioconazole, was assessed. Finally, the viability of Escherichia coli (E. coli) and C. albicans were detected on the portable microfluidic chip system. PMAxx-LAMP based portable microfluidic chip system was determined to be a feasible technique for assessing the viability of multiple pathogens in gynecology and might provide insights into new VVC treatment strategies.

Prevalence of vulvovaginal candidiasis in Brazil: a systematic review

Vulvovaginal candidiasis (CVV) is a condition whose signs and symptoms are related to inflammation caused by Candida spp infection. It is the second leading cause of vaginitis in the world, representing a public health problem. The present systematic review comes with the proposal of analyze and identify the available evidence on CVV prevalence in Brazil, pointing out its variability by regions. For this, a systematic literature review was carried out with meta-analysis of cross-sectional and cohort studies, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guide recommendations, and was registered in the International Prospective Register of Systematic Reviews (PROSPERO 2020 CRD42020181695). The databases used for survey were LILACS, Scielo, Scopus, PUBMED, Web of Science and CINAHL. Fifteen studies were selected to estimate CVV prevalence in the Brazilian territory. South and Southeast regions have higher prevalences than the North and Northeast regions, no data were found for the Midwest region. The estimated prevalence for Brazil is 18%, however, it is suggested that this number is higher due to underreporting and the presence of asymptomatic cases. Therefore, new epidemiological studies are recommended throughout Brazil, to elucidate the profile of this disease in the country, in addition to assisting in the elaboration of an appropriate prevention plan by state.

LAY ABSTRACT

Data found in the literature regarding the epidemiological profile of VVC in Brazil are obsolete and incomplete, so the present systematic review has the proposal to analyze and identify the evidence on VVC prevalence in Brazil. The estimated prevalence is 18%, however, this number can be higher.

Short communication: Characterization of vaginal fungal communities in healthy women and women with bacterial vaginosis (BV); a pilot study

The role of the vaginal fungal community, the mycobiota, in women's health is an emerging area of research. Utilization of novel molecular technology enables more in-depth characterization and identification of fungal diversity, and their potential associations to health. The present study is a substudy of a larger observational clinical trial investigating the vaginal microbiota composition before and after antibiotic treatment for Bacterial Vaginosis (BV) infection in comparison to the microbiota of healthy women (Clinicaltrials.gov identifier: NCT03187). Here, we characterized the vaginal mycobiota by sequencing the internal transcribed spacer (ITS) 2 region from vaginal microbial DNA collected from healthy women and women with BV and in relation to their treatment with oral metronidazole. Interestingly, both ascomycetous and basidiomycetous yeasts and filamentous fungi consisting of more than 30 different species were detectable from 21 out of 94 vaginal swab samples. The mycobiota was dominated by Candida species (>60% of relative abundance) and especially with Candida albicans in both study groups. The abundance of C. albicans was inversely correlated with fungal diversity but did not correlate with Nugent scores. Metronidazole did not seem to have a major effect on the relative abundance of C. albicans. The results revealed the diversity of the fungal community within healthy and BV-infected women, which is worth exploring further.

Escherichia coli enhances the virulence factors of Candida albicans, the cause of vulvovaginal candidiasis, in a dual bacterial/fungal biofilm

Co-infection with other microorganisms can promote the Candida albicans to be invasive. In this study, Escherichia coli and C. albicans were co-isolated from the women with candidiasis symptoms. The in vitro effects of E. coli on C. albicans hypha development, biofilm formation, antibiotic susceptibility, dispersion from the biofilm, expression of Als3, Hwp1, and Tup1 genes, and pathogenesis in Galleria mellonella were investigated. Electron microscopic images revealed that hypha induction was markedly increased in the bacteria-fungi co-culture. Biofilm formation was increased 2.2 fold in the presence of E. coli. The minimum inhibitory concentration of nystatin against Candida was increased from (μg mL^-1) 25 to 50 in the dual biofilm. Candida dissemination was increased up to 2.7 fold from the mixed fungi/bacteria biofilm. The expression of ALS3 and HWP1 genes was increased (5.9 and 2.0 fold, respectively) while the TUP1 gene expression was decreased (0.4 fold) when C. albicans was incubated with E. coli. The simultaneous injection of C. albicans and E. coli to the insect larvae increased Galleria mortality up to 40%. This study demonstrated the effects of E. coli to promote fungi virulence factors, which suggest polymicrobial interaction should be considered during treatment of fungal infections.

Vaginal Probiotics for Reproductive Health and Related Dysbiosis: Systematic Review and Meta-Analysis

The use of probiotics in reproductive-related dysbiosis is an area of continuous progress due to the growing interest from clinicians and patients suffering from recurrent reproductive microbiota disorders. An imbalance in the natural colonization sites related to reproductive health—vaginal, cervicovaginal, endometrial, and pregnancy-related altered microbiota—could play a decisive role in reproductive outcomes. Oral and vaginal administrations are in continuous discussion regarding the clinical effects pursued, but the oral route is used and studied more often despite the need for further transference to the colonization site. The aim of the present review was to retrieve the standardized protocols of vaginal probiotics commonly used for investigating their microbiota modulation capacities. Most of the studies selected focused on treating bacterial vaginosis (BV) as the most common dysbiosis; a few studies focused on vulvovaginal candidiasis (VVC) and on pretreatment during in vitro fertilization (IVF). Vaginal probiotic doses administered were similar to oral probiotics protocols, ranging from ≥10⁷ CFU/day to 2.5 × 10¹⁰ CFU/day, but were highly variable regarding the treatment duration timing. Moderate vaginal microbiota modulation was achieved; the relative abundance of abnormal microbiota decreased and Lactobacillus species increased.

Vaginotypes of the human vaginal microbiome

The human vaginal environment harbours a community of bacteria that plays an important role in maintaining vaginal health and in protecting this environment from various urogenital infections. This bacterial population, also known as vaginal microbiota, has been demonstrated to be dominated by members of the Lactobacillus genus. Several studies employing 16S rRNA gene-based amplicon sequencing have classified the vaginal microbiota into five distinct community state types (CSTs) or vaginotypes. To deepen our understanding of the vaginal microbiota we performed an in-depth meta-analysis of 1312 publicly available datasets concerning healthy vaginal microbiome information obtained by metagenomics sequencing. The analysis confirmed the predominance of taxa belonging to the Lactobacillus genus, followed by members of the genera Gardnerella, Vibrio and Atopobium. Moreover, the statistical robustness offered by this meta-analysis allowed us to disentangle the species-level composition of dominant and accessory taxa constituting each vaginotype and to revisit and refine the previously proposed CST classification. In addition, a functional characterization of the metagenomic datasets revealed particular genetic features associated with each assigned vaginotype.

Promising Drug Delivery Approaches to Treat Microbial Infections in the Vagina: A Recent Update

An optimal host-microbiota interaction in the human vagina governs the reproductive health status of a woman. The marked depletion in the beneficial Lactobacillus sp. increases the risk of infection with sexually transmitted pathogens, resulting in gynaecological issues. Vaginal infections that are becoming increasingly prevalent, especially among women of reproductive age, require an effective concentration of antimicrobial drugs at the infectious sites for complete disease eradication. Thus, topical treatment is recommended as it allows direct therapeutic action, reduced drug doses and side effects, and self-insertion. However, the alterations in the physiological conditions of the vagina affect the effectiveness of vaginal drug delivery considerably. Conventional vaginal dosage forms are often linked to low retention time in the vagina and discomfort which significantly reduces patient compliance. The lack of optimal prevention and treatment approaches have contributed to the unacceptably high rate of recurrence for vaginal diseases. To combat these limitations, several novel approaches including nano-systems, mucoadhesive polymeric systems, and stimuli-responsive systems have been developed in recent years. This review discusses and summarises the recent research progress of these novel approaches for vaginal drug delivery against various vaginal diseases. An overview of the concept and challenges of vaginal infections, anatomy and physiology of the vagina, and barriers to vaginal drug delivery are also addressed.

Distinct Functional Traits of Lactobacilli from Women with Asymptomatic Bacterial Vaginosis and Normal Microbiota

Asymptomatic bacterial vaginosis (BV) in reproductive-age women has serious obstetric and gynecological consequences. Despite its high incidence, the behavior of vaginal lactobacilli in asymptomatic BV is unknown. We analyzed the functional properties of previously isolated vaginal lactobacilli from asymptomatic women with normal, intermediate, and BV microbiota. Lactic acid and antimicrobial activity against seven urogenital pathogens were evaluated from lactobacilli cell-free culture supernatants (CFCs) (n = 207) after 48 h incubation in MRS. Lactobacilli isolates were used to evaluate H2O2, autoaggregation and coaggregation with C. albicans. Lactobacilli from normal microbiota produced more d-lactate than lactobacilli from intermediate and asymptomatic BV (p = 0.007). L. plantarum, L. fermentum and L. reuteri produced greater d-lactate whereas L. rhamnosus, L. crispatus, L. johnsonii were greater producers of l-lactate. Interspecies positive correlation was observed in the lactic acid contents of CFCs. Distribution of H2O2-producing lactobacilli did not vary significantly among the groups. When lactic acid isomers were considered, species from intermediate and BV microbiota clustered together with each other and distinctly from species of normal microbiota. Broad-spectrum antagonism (≥90% inhibition) against E. coli, C. albicans, S. aureus, P. aeruginosa, G. vaginalis, N. gonorrhoeae, S. agalactiae were displayed by 46.86% (97) of isolates. Our study highlights the differential functional properties of vaginal lactobacilli from women with normal microbiota and asymptomatic BV.

Probiotic intervention as a potential therapeutic for managing gestational disorders and improving pregnancy outcomes

Recent molecular investigations have significantly developed our knowledge of the characteristics of the reproductive microbiome and their associations with host responses to provide an ideal milieu for the development of the embryo during the peri-implantation period and throughout pregnancy as well as to provide a successful in vitro fertilization and appropriate reproductive outcomes. In this context, the establishment of microbial homeostasis in the female reproductive tract, in various physiological periods, is a substantial challenge, which appears the application of probiotics can facilitate the achievement of this goal. So that, currently, probiotics due to its safe and natural features can be considered as a novel biotherapeutic approach. In this review, we comprehensively discuss the bacterial, fungal, and viral diversity detected in the reproductive tract, and their associations with the establishment of dysbiosis/eubiosis conditions as well as we present the significant outcomes on probiotic intervention as an efficient biotherapeutic strategy for management of gestational disorders and improve pregnancy outcomes.

Perinuclear Anti-Neutrophil Cytoplasmic Antibodies (pANCA) Impair Neutrophil Candidacidal Activity and Are Increased in the Cellular Fraction of Vaginal Samples from Women with Vulvovaginal Candidiasis

Vulvovaginal candidiasis (VVC) is primarily caused by Candida albicans and affects 75% of childbearing age women. Although C. albicans can colonize asymptomatically, disease is associated with an increased Candida burden, a loss of epithelial tolerance and a breakdown in vaginal microbiota homeostasis. VVC symptoms have been ascribed to a powerful inflammatory response associated with the infiltration of non-protective neutrophils (PMN). Here, we compared the immunological characteristics of vaginal fluids and cellular protein extracts obtained from 28 VVC women and from 23 healthy women colonized by Candida spp. We measured the levels of antibodies against fungal antigens and human autoantigens (anti-Saccharomyces cerevisiae antibodies (ASCA), C. albicans germ tube antibodies (CAGTAs) and perinuclear anti-neutrophil cytoplasmic antibodies (pANCA)), in addition to other immunological markers. Our results show that the pANCA levels detected in the cellular protein extracts from the vaginal fluids of symptomatic women were significantly higher than those obtained from healthy colonized women. Consistent with a potential physiologically relevant role for this pANCA, we found that specific anti-myeloperoxidase antibodies could completely neutralize the ex vivo killing capacity of polymorphonuclear cells. Collectively, this preliminary study suggests for the first time that pANCA are found in the pathogenic vaginal environment and can promptly impair neutrophil function against Candida, potentially preventing a protective response.

Probiotics Dietary Supplementation for Modulating Endocrine and Fertility Microbiota Dysbiosis

Human microbiota seems to play a key role in endocrine and reproductive systems. Fortunately, microbiota reproductive dysbiosis start to be treated by probiotics using typical species from genus Lactobacillus. This work presents the compiled and analysed results from the most up-to-date information from clinical trials regarding microbiota, fertility, probiotics and oral route administration, reviewing open access scientific documents. These studies analyse the clinical impact of probiotics administered on several endocrine disorders' manifestations in women: mastitis; vaginal dysbiosis; pregnancy complication disorders; and polycystic ovary syndrome. In all cases, the clinical modulation achieved by probiotics was evaluated positively through the improvement of specific disease outcomes with the exception of the pregnancy disorders studies, where the sample sizes results were statistically insufficient. High amounts of studies were discarded because no data were provided on specific probiotic strains, doses, impact on the individual autochthon microbiota, or data regarding specific hormonal values modifications and endocrine regulation effects. However, most of the selected studies with probiotics contained no protocolised administration. Therefore, we consider that intervention studies with probiotics might allocate the focus, not only in obtaining a final outcome, but in how to personalise the administration according to the disorder to be palliated.

Vulvovaginal Candidiasis: A Current Understanding and Burning Questions

Candida albicans, along with other closely related Candida species, are the primary causative agents of vulvovaginal candidiasis (VVC)-a multifactorial infectious disease of the lower female reproductive tract resulting in pathologic inflammation. Unlike other forms of candidiasis, VVC is a disease of immunocompetent and otherwise healthy women, most predominant during their child-bearing years. While VVC is non-lethal, its high global incidence and profound negative impact on quality-of-life necessitates further understanding of the host and fungal factors that drive disease pathogenesis. In this review, we cover the current state of our understanding of the epidemiology, host response, fungal pathogenicity mechanisms, impact of the microbiome, and novel approaches to treatment of this most prevalent human candidal infection. We also offer insight into the latest advancements in the VVC field and identify important questions that still remain.

Effect of Oral Probiotic Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 on the Vaginal Microbiota, Cytokines and Chemokines in Pregnant Women

Spontaneous preterm birth is associated with vaginal microbial dysbiosis. As certain strains of lactobacilli help restore homeostasis in non-pregnant women, the goal was to determine the effect of Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 administered orally, twice daily for 12 weeks on the vaginal microbiota, cytokines and chemokines of low-risk pregnant women. A double-blind, placebo-controlled, randomized trial comparing probiotic lactobacilli to placebo daily was performed in 86 asymptomatic pregnant women who had an Intermediate or Bacterial Vaginosis Nugent score at 13 weeks. After drop outs, 32 women receiving probiotics and 34 receiving placebo completed the study. The Nugent score returned to normal in 30% of the women in both groups at 28 weeks and was maintained until 35 weeks. The majority of subjects had normal pregnancy outcomes. Ninety-three bacterial species were detected at 13 weeks, with Lactobacillus iners, Lactobacillus crispatus, Gardnerella vaginalis and Atopobium vaginae being the most abundant across pregnancy. There was no difference in the Shannon diversity index between the probiotic and placebo groups at 13, 28 or 35 weeks. Almost all subjects consumed fermented foods and many of the organisms in the vagina are also known to be present in fermented foods. Interleukin-4 in the placebo group and Interleukin-10 in both probiotic and placebo groups increased slightly at 28 weeks but were not different at 35 weeks when compared to 13 weeks. In conclusion, this study showed no adverse issues resulting from 12 week use of probiotic Lactobacillus strains GR-1 and RC-14 during pregnancy in women at low risk for premature birth. The vaginal microbiota demonstrated flux irrespective of this oral probiotic administration.