Candida albicans Modulates Murine and Human Beta Defensin-1 during Vaginitis

Vulvovaginal candidiasis (VVC) and recurrent vulvovaginal candidiasis (RVVC) are two forms of a disease caused by Candida spp. β-defensin (BD) is one of the most important families of antimicrobial peptides in the female genital tract and includes molecules that exert essential local functions as antimicrobial and PMN chemoattractant peptides. However, the information on their role during murine and human VVC and RVVC is limited. Thus, we analyzed the behavior and contribution of BD1 to the local response in a VVC mice model and the local cytokine profile and human BD1 and BD3 expression in cervicovaginal lavage from patients with VVC and RVVC. We demonstrated that, in patients with RVVC BD1, mRNA and protein expression were severely diminished and that the aspartate proteinase and lipase secreted by C. albicans are involved in that decrease. This study provides novel information about the pathogenesis of VVC and describes a highly efficient C. albicans escape strategy for perpetuating the infection; these results may contribute to the development of new or combined treatment approaches.

Characterization of vaginal microbial enzymes identifies amylopullulanases that support growth of Lactobacillus crispatus on glycogen

The healthy human vaginal microbiota is generally dominated by Lactobacilli, and the transition to a more diverse community of anaerobic microbes is associated with a number of health risks. While the mechanisms underlying the stability of Lactobacillus-dominated vaginal communities are not fully understood, competition for nutrients is a likely contributing factor. Glycogen secreted by epithelial cells is widely believed to support the growth of vaginal microbes. However, the mechanism by which bacteria access sugars from this complex polymer is unclear, with evidence to support a role for both microbial and human enzymes. To shed light on the potential contribution from microbial enzymes, here we biochemically characterize six glycogen-degrading enzymes predicted to be secreted by vaginal bacteria and confirm their ability to support the growth of an amylase-deficient strain of L. crispatus on glycogen. We reveal significant differences in the pH tolerance between enzymes from different organisms, suggesting the adaptation of Lactobacilli to an acidic vaginal environment. Using a simple assay specific for the microbial enzymes, we confirm their presence in cervicovaginal lavage samples. Finally, we demonstrate the selective inhibition of glycogen-degrading enzymes from two vaginal microbes associated with dysbiosis. This work provides biochemical evidence to support the role of vaginal bacterial amylase enzymes in the breakdown of glycogen, providing insight into factors that shape the vaginal microbiota and highlighting the possibility of manipulating community structure via non-antibiotic small molecules.

Association between cervical dysplasia and female genital schistosomiasis diagnosed by genital PCR in Zambian women

Background Female genital schistosomiasis (FGS) is a neglected tropical gynaecological disease that affects millions of women in sub-Saharan Africa (SSA). FGS is caused by Schistosoma haematobium, a parasitic carcinogen involved in the pathogenesis of squamous cell carcinoma of the bladder. Cervical cancer incidence and mortality are highest in SSA, where pre-cancerous cervical dysplasia is often detected on screening with visual inspection with acetic acid (VIA). There are no studies evaluating the association between VIA positivity and FGS diagnosed by genital PCR. Methods Women were recruited from the Bilharzia and HIV (BILHIV) study in Zambia a community-based study comparing genital self-sampling to provider obtained cervicovaginal-lavage for the diagnosis of FGS in women aged 18–31. FGS was defined as positive Schistosoma DNA from any genital PCR. Urogenital schistosomiasis diagnostics included urine circulating anodic antigen, urine microscopy and portable colposcopy. Participants were offered cervical cancer screening using VIA at Livingstone Central Hospital. Associations of PCR confirmed FGS and other diagnostics with VIA positivity were assessed using multivariable logistic regression. Results VIA results were available from 237 BILHIV participants. A positive Schistosoma PCR in any genital specimen was detected in 14 women (5.9%), 28.6% (4/14) of these women had positive VIA compared to 9.0% without PCR evidence of schistosome infection (20/223). Schistosoma PCR positivity in any genital specimen was strongly associated with VIA positivity (OR: 6.08, 95% CI: 1.58–23.37, P = 0.02). Conclusions This is the first study to find an association between FGS and positive VIA, a relationship that may be causal. Further longitudinal studies are needed.

Fractional CO2 laser treatment effect on cervicovaginal lavage zinc and copper levels: a prospective cohort study

Background The basic principle of vaginal laser therapy is the rejuvenation of the affected tissue. Zinc and copper are essential nutritional trace elements and have a key role in connective tissue homeostasis. We aimed to investigate the effect of vaginal, fractional CO2 laser treatment on cervicovaginal lavage (CVL) zinc and copper levels. Methods Twenty-nine postmenopausal women with symptoms of vaginal dryness were enrolled in our prospective cohort study. Three treatments with MonaLisa Touch CO2 laser system were performed four weeks apart. At each treatment CVL was collected, Vaginal Health Index (VHI) was obtained, and Visual Analog Scale (VAS) for vaginal dryness was assigned by patients. Zinc and copper concentrations were measured with optical emission spectrometry before each treatment and six weeks after the 3rd treatment. Results The VHI scores significantly improved after each laser treatment (mean ± SD VHI score, 13.03 ± 4.49 before vs. 15.55 ± 4.35 after the 1st, 17.79 ± 4.57 after the 2nd and 19.38 ± 4.39 after the 3rd treatment, P < 0.01). Similarly, VAS scores reflected improvement (mean ± SD VAS score 6.59 ± 2.86 before vs. 4.17 ± 2.86 after the 1st, 2.45 ± 2.43 after the 2nd and 1.41 ± 1.94 after the 3rd treatment, P < 0.01). CVL zinc levels were significantly higher compared to copper levels (0.06 ± 0.04 vs. 0.006 ± 0.006 mg/L, P < 0.01) at baseline. While copper levels remained the same through treatments, the CVL zinc level was significantly higher after the second laser treatment compared to the baseline. Conclusions Fractional CO2 laser treatment of the vagina impacts CVL zinc and copper levels differently. While CVL copper levels were not different after each laser treatment, zinc levels were significantly higher after the second treatment before returning to baseline values.

Association Between Cervical Dysplasia and Female Genital Schistosomiasis Diagnosed by Genital PCR in Zambian Women

Background: Female genital schistosomiasis (FGS) is a neglected tropical gynaecological disease that affects millions of women in sub-Saharan Africa (SSA). FGS is caused by Schistosoma (S.) haematobium, a parasitic carcinogen involved in the pathogenesis of squamous cell carcinoma of the bladder. Cervical cancer incidence and mortality are highest in SSA, where pre-cancerous cervical dysplasia is often detected on screening with visual inspection with acetic acid (VIA). No studies have evaluated the association between VIA positivity and FGS diagnosed by genital PCR. Methods: Women were recruited from the BILHIV study in Zambia, which compared genital self-sampling to provider obtained cervicovaginal-lavage for the diagnosis of FGS in women aged 18-31. FGS was defined as positive Schistosoma DNA from any genital PCR. Urogenital schistosomiasis diagnostics included urine circulating anodic antigen, urine microscopy and portable colposcopy. Participants were offered cervical cancer screening using VIA at Livingstone Central Hospital. Associations of PCR confirmed FGS and other diagnostics with VIA positivity were assessed using multivariable logistic regression.Results: VIA results were available from 237 BILHIV participants. A positive Schistosoma PCR in any genital specimen was detected in 14 women (5.9%), 28.6% (4/14) of these women had positive VIA compared to 9.0% (20/223) without PCR evidence of schistosome infection. Schistosoma PCR positivity in any genital specimen was strongly associated with VIA positivity (OR: 6.08, 95% CI: 1.58-23.37, P=0.02). Conclusions: This is the first study to find an association between FGS and positive VIA, a relationship that may be causal. Further longitudinal studies are needed.

Genetic variation in Toll-like receptor-5 and colonization with flagellated bacterial vaginosis-associated bacteria

Bacterial vaginosis (BV) is a vaginal dysbiotic condition linked to negative gynecological and reproductive sequelae. Flagellated bacteria have been identified in women with BV, including Mobiluncus spp. and BV-associated bacterium-1 (BVAB1), an uncultivated, putatively flagellated species. The host response to flagellin mediated through toll-like receptor-5 (TLR5) has not been explored in BV. Using independent discovery and validation cohorts, we examined the hypothesis that TLR5 deficiency–defined by a dominant negative stop codon polymorphism rs5744168–is associated with an increased risk for BV and increased colonization with flagellated bacteria associated with BV (BVAB1, Mobiluncus curtisii, Mobiluncus mulieris). TLR5 deficiency was not associated with BV status and TLR5 deficient women had decreased colonization with BVAB1 in both cohorts. We stimulated HEK-hTLR5-overexpressing, NF-kB reporter cells with whole, heat-killed M. mulieris or M. curtisii, and with partially purified flagellin from these species; as BVAB1 is uncultivated, we used cervicovaginal lavage (CVL) supernatant from women colonized with BVAB1 for stimulation. While heat-killed M. mulieris and CVL from women colonized with BVAB1 stimulate a TLR5-mediated response, heat-killed M. curtisii did not. In contrast, partially purified flagellin from both Mobiluncus species stimulated a TLR5-mediated response in vitro. We observed no correlation between vaginal IL-8 and flagellated BVAB concentrations among TLR5 sufficient women. Inter-species variation in accessibility of flagellin recognition domains may be responsible for these observations as reflected in the potentially novel flagellin products encoded by Mobiluncus species versus those encoded by BVAB1.

Acceptability and feasibility of genital self-sampling for the diagnosis of female genital schistosomiasis: a cross-sectional study in Zambia

Background: Female genital schistosomiasis (FGS) is a neglected and disabling gynaecological disorder that is difficult to diagnose and is part of the wider spectrum of urogenital disease caused by the waterborne parasite Schistosoma haematobium. Over 90% of human schistosomiasis cases are found in sub-Saharan Africa with 3.8 million people infected with schistosomes in Zambia. Reported FGS prevalence ranges from 33-75% of those with urinary schistosomiasis in endemic areas, suggesting a potentially high FGS burden in Zambia alone. The Bilharzia and HIV (BILHIV) study evaluated home self-sampling genital collection methods for the diagnosis of FGS. Methods: Eligible participants included non-pregnant, sexually active women aged 18-31 who were previously recruited for the HPTN 071 (PopART) trial in Livingstone, Zambia. Household demographic and symptom questionnaires were administered by community workers. Participants were offered vaginal and cervical self-swabs and a urine cup. Cervicovaginal lavage (CVL) was performed in clinic by midwives. Information was collected from participants on the acceptability and feasibility of genital self-sampling. Results: From January-August 2018, 603 women were enrolled, and 87.3% (527/603) completed clinic follow up. A high proportion of participants indicated that self-collection of specimens was “easy” or “very easy” on a 5-point Likert scale. A high proportion of women would be willing to self-collect all three specimens again in future: vaginal swab 96.7% (583/603), cervical swab 96.5% (582/603), and urine 96.2% (580/603). Overall, 90.0% (543/603) preferred to self-collect samples at home, compared with sampling in the clinic Home-based self-sampling was preferred over provider-based sampling in the clinic due to greater privacy 65.0% (353/543), convenience 51.4% (279/543) and lack of needed transportation 17.7% (96/543). Conclusions: Home based genital self-sampling for FGS diagnosis is highly acceptable. This scalable method may inform future efforts for community-based diagnosis of FGS