Group B Streptococcus CAMP Factor Does Not Contribute to Interactions with the Vaginal Epithelium and Is Dispensable for Vaginal Colonization in Mice

Group B Streptococcus (GBS) remains a pervasive pathogen for pregnant women and their newborns. Maternal screening and intrapartum antibiotic prophylaxis to GBS-positive mothers have reduced, but not eliminated GBS neonatal disease, and have not impacted GBS-associated preterm birth or stillbirth.

Receptor-related aspects of reduced lubrication in women of reproductive age with hypoandrogenism

Aim — to investigate receptivity of the vaginal epithelium in women with the female sexual dysfunction and hypoandrogenism.Materials and methods. The immunohistochemical investigation has been performed to define the density of androgen receptors (AR) and estrogen receptors (ER) in the distal part of the vaginal tract of women of reproductive age with hypoandrogenic provision of their hormonal background. For immunohistological examination, a biopsy of the lower third of the vaginal mucosa was taken using a dermopunch with a diameter of 3 mm in 20 women with female sexual dysfunction (FSD) and hypo­andro­genism. The control group consisted of 20 women of reproductive age without FSDmanifestations and disturbances in their hormonal levels. The survey was carried out at the stage of pre-conceptional preparation. Location: Ukrainian Scientific and Prac­tical Center for Endocrine Surgery, Transplantation of Endocrine Organs and Tissues of the Ministry of Health of Ukraine.Results. Immunoreactivity of ERα in the epithelium in the main and control groupswas 47.2 ± 22.2 and 86.1 ± 8.0 (p < 0.001), in the stroma — respectively 13.9 ± 16.8 and 86.1 ± 8.3 (p < 0.001), that is, immunoreactivity in the epithelium was significantly higher thanin the stroma (p < 0,01). The ERα locationin the vaginal epithelium was the samein both groups: cellsof the basal-intermediate layer along the basement membrane and the intermediate layer. No cells, expressing ERα, were detected in the surface layer. In stromal cells, ERαcontained in fibroblasts and smooth muscle cells. ERβ was found in cellsof thebasal — parabasal layer, the intermediate layer, occasionally —on the surface layerof vaginal epithelium, as well as in fibroblasts, vascular endothelium, where both nuclear andcytoplasmic staining was revealed. According to the results of immunohistochemical study of AR invagina, the proportion of AR-positive cells in healthy women was negligible (3.8 ± 2.2), that is considerably less than in patients with androgen deficiency (18.8 ± 8.3) and compared withother receptors. AR were localized mainly in the basal layer alongbasement membrane. Single AR-positive fibroblasts occurred in the stroma.Conclusions. Estrogen receptors α (ERα) are involved in the regulation of the processes of proliferation and differentiation of the vaginal epithelium under the influence of estrogen, as evidenced by a 1.8-fold increase in the density of stained ERα in women of the control group. The absence of correlations between ЕRα and ЕRβ receptors (r = 0.24; p < 0.05) may indicate the ability to change in the same tissue depending on the strength of estrogen effects on the body of a woman. Topical localization of androgen receptors in the basal layer testifies in favour of the safe use of local formsof androgensto overcome the reduced lubrication.

Induced Dryness Stress on Human Vaginal Epithelium: The Efficacy of a New Vaginal Gel

An experimental model of dryness on vaginal mucosa is proposed to assess the efficacy of a new vaginal gel (Respecta® Hydragel Ref 17031). The dryness model was induced on reconstituted human vaginal epithelium (HVE) by incubating the tissues in modified environmental conditions (R.H. < 50% and T = 40 °C) for 48 h. The products were applied on the ‘Dry’ HVE models for 24 h (series 48 h + 24 h) in standard culture conditions (37 °C 5% CO2). Their efficacy in counteracting vaginal dryness was assessed and compared to tissues treated with saline solution and cultured in standard culture conditions (negative control) and to untreated tissues incubated in dryness conditions for 48 h and then recovered after 24 h in standard culture conditions (positive control). The products’ efficacy was quantified by measuring the following parameters: (1) water flux and direct moisturization by AQP3 immunohistochemical staining, and (2) maintenance of moisturization and elasticity of the mucosa by hyaluronic acid (CD44) immunofluorescence staining. Respecta® Hydragel demonstrated efficacy in regulating the water flux by inducing AQP3 expression thus determining a positive water balance within the vaginal epithelium. It induced a remodelling of the epithelium morphology with restored trophism compared to the dry HVE control. Furthermore, it demonstrated a significant increase of the expression of CD44, related to hyaluronic acid (HA) distribution in the extracellular matrix. HA has the ability to act on the cellular matrix composition and its renewal compared to the dry HVE control. Through these mechanisms it induces a deep hydration and elasticity of the vaginal mucosa.

Vaginal mucus in mice: Developmental and gene expression features of epithelial mucous cells during pregnancy

The vagina is the site of copulation and serves as the birth canal. It also provides protection against external pathogens. In mice, due to the absence of cervical glands, the vaginal epithelium is the main producer of vaginal mucus. The development and differentiation of vaginal epithelium-constituting cells and the molecular characteristics of vaginal mucus have not been thoroughly examined. Here, we characterized vaginal mucous cell development and the expression of mucus-related factors in pregnant mice. The vaginal mucous epithelium layer thickened and became multilayered after day 12 of pregnancy and secreted increasing amounts of mucus until early postpartum. Using histochemistry and transmission electron microscopy, we found supra-basal mucous cells as probable candidates for precursor cells. In vaginal mucous cells, the expression of TFF1, a stabilizer of mucus, was high, and some members of mucins and antimicrobial peptides (MUC5B and DEFB1) were expressed in a stage-dependent manner. In summary, this study presents the partial characterization of vaginal epithelial mucous cell lineage and expression of genes encoding several peptide substances that may affect vaginal tissue homeostasis and mucosal immunity during pregnancy and parturition.

Observational cohort study of the effect of a single lubricant exposure during transvaginal ultrasound on cell-shedding from the vaginal epithelium

The outer layers of the vaginal epithelium (VE) are important because they accumulate glycogen which, under optimal conditions, Lactobacillus spp. consume to grow and acidify the vaginal microenvironment with lactic acid. We hypothesized that exposure to lubricant, for example in the conduct of a transvaginal ultrasound (TVUS), may contribute to the shedding of mature epithelial cells, exposing immature cells. Cervicovaginal fluid (CVF) was sampled at four time points by menstrual cup (Softdisc™) from 50 women referred for TVUS, during which a controlled volume of lubricant was applied to the TVUS wand. Samples were collected (1) immediately before TVUS and (2) 6–12 hours, (3) within one week, and (4) two weeks after TVUS. Clinical vaginal lubricants are similar to commercial lubricants, and often have a high osmolality or pH, and contain bactericides such as methylparaben and propylparaben. The number and maturity of epithelial cells in each CVF sample were measured by quantitative and differential fluorimetry (maturity index, MI). Comparisons of cell-counts and maturity were made by paired Wilcoxon signed-rank tests. Among women with a high pre-TVUS MI (> 3), there was a decrease in median cell-count and mean MI in the sample collected 6–12 hours after TVUS (p<0.001, n = 26 and p < 0.001, n = 26, respectively). For these women, cell-count and MI remained lower in the sample collected within the subsequent week (p<0.001, n = 29 and p<0.01, n = 29, respectively), and MI remained lower in the sample collected within two weeks of TVUS (p<0.01, n = 25), compared to the pre-TVUS sample. Among participants with a low pre-TVUS MI (< 3), cell-count was higher in the sample collected within two weeks of TVUS compared to the pre-TVUS sample (p = 0.03, n = 15), but no significant changes in MI were observed. Results were similar when restricted to reproductive-age women. This preliminary data indicates hypertonic vaginal lubricants may increase vaginal epithelial cell shedding.

Trichomonas vaginalis infection impairs anion secretion in vaginal epithelium

Trichomonas vaginalis is a common protozoan parasite, which causes trichomoniasis associated with severe adverse reproductive outcomes. However, the underlying pathogenesis has not been fully understood. As the first line of defense against invading pathogens, the vaginal epithelial cells are highly responsive to environmental stimuli and contribute to the formation of the optimal luminal fluid microenvironment. The cystic fibrosis transmembrane conductance regulator (CFTR), an anion channel widely distributed at the apical membrane of epithelial cells, plays a crucial role in mediating the secretion of Cl− and HCO3−. In this study, we investigated the effect of T. vaginalis on vaginal epithelial ion transport elicited by prostaglandin E2 (PGE2), a major prostaglandin in the semen. Luminal administration of PGE2 triggered a remarkable and sustained increase of short-circuit current (ISC) in rat vaginal epithelium, which was mainly due to Cl− and HCO3− secretion mediated by the cAMP-activated CFTR. However, T. vaginalis infection significantly abrogated the ISC response evoked by PGE2, indicating impaired transepithelial anion transport via CFTR. Using a primary cell culture system of rat vaginal epithelium and a human vaginal epithelial cell line, we demonstrated that the expression of CFTR was significantly down-regulated after T. vaginalis infection. In addition, defective Cl− transport function of CFTR was observed in T. vaginalis-infected cells by measuring intracellular Cl− signals. Conclusively, T. vaginalis restrained exogenous PGE2-induced anion secretion through down-regulation of CFTR in vaginal epithelium. These results provide novel insights into the intervention of reproductive complications associated with T. vaginalis infection such as infertility and disequilibrium in vaginal fluid microenvironment.

The Immunolocalization of Cadherins and Beta-Catenin in the Cervix and Vagina of Cycling Cows

The adherens junction (AJ) maintains the structural integrity and barrier function of the epithelial cell layers. AJs also play a key role in a variety of biological and pathological processes, from morphogenesis to tumor progression. AJs perform these functions through the cadherin-catenin adhesion complex. In this study, we investigated the presence, cell-specific localization, and temporal distribution of AJ components such as cadherins and beta-catenin in the cow cervix and vagina during the oestrous cycle using immunohistochemistry. The cow genitalia (n = 30) were collected from an abattoir and the cervix and vagina were categorized into the follicular and luteal groups based on cyclicity. Results demonstrated constitutive expression of beta-catenin and placental (P)- and epithelial (E)-cadherins, but not neural (N)-cadherin, in ciliated and non-ciliated columnar cervical cells, the luminal, parabasal, intermediate, and basal layers of the stratified vaginal epithelium of the bovine cervix and vagina throughout the oestrous cycle. The honeycomb-like membrane staining pattern for selected junctional molecules was observed in the epithelial cells. While there were no noticeable variations in the immunostaining intensity of P- and E-cadherin and beta-catenin proteins in the cervical and vaginal epithelium between the oestrous phases, the immunolocalization patterns altered by structural changes that occurred in response to oestrogen and progesterone hormone levels during the oestrous cycle. These results may indicate that P- and E-cadherin and beta-catenin participate in maintaining the integrity and barrier function of the cervical and vaginal epithelium throughout the oestrous cycle, thus helping to maintain the sterility of the uterine cavity.

Physiological Features of the Reproductive System of Female Nutria

This article provides information about a promising alternative field of animal husbandry – nutria breeding. This involves the production of fur and high-quality meat products, which contain a large amount of nitrogenous extractives and muscle hemoglobin. This study examined the sexual system of female nutria, and the dynamics, duration and features of each stage of the female nutria’s sexual cycle, including estrus, sexual arousal, hunting, braking and phase balancing. The methods of observation, clinical examination, research of smears and fingerprints, and analysis of the cytogram of the vaginal epithelium at different stages of sexual and physiological maturity of female nutria were used. When analyzing the cytogram of the vaginal epithelium, the structure, color, and percentage of basal, parabasal, superficial, and keratinized cells were indicated. Information about the timing of sexual and physiological maturity, their features, processes and signs of manifestation, and different timing of sexual and physiological maturity in summer and winter is provided. Keywords: nutria, female, puberty, physiological maturity