scholarly journals Coassociation between Group BStreptococcusandCandida albicansPromotes Interactions with Vaginal Epithelium

2018 ◽  
Vol 86 (4) ◽  
Author(s):  
Grace R. Pidwill ◽  
Sara Rego ◽  
Howard F. Jenkinson ◽  
Richard J. Lamont ◽  
Angela H. Nobbs
Keyword(s):  
Risk Factor ◽  
Opportunistic Pathogen ◽  
Vaginal Epithelium ◽  
Genitourinary Tract ◽  
Epithelial Cell Line ◽  
Vaginal Mucosa ◽  
Content Type ◽  
Vaginal Colonization ◽  
Group B ◽  
Vaginal Thrush

ABSTRACTGroup BStreptococcus(GBS) is a leading cause of neonatal sepsis, pneumonia, and meningitis worldwide. In the majority of cases, GBS is transmitted vertically from mother to neonate, making maternal vaginal colonization a key risk factor for neonatal disease. The fungusCandida albicansis an opportunistic pathogen of the female genitourinary tract and the causative agent of vaginal thrush. Carriage ofC. albicanshas been shown to be an independent risk factor for vaginal colonization by GBS. However, the nature of interactions between these two microbes is poorly understood. This study provides evidence of a reciprocal, synergistic interplay between GBS andC. albicansthat may serve to promote their cocolonization of the vaginal mucosa. GBS strains NEM316 (serotype III) and 515 (serotype Ia) are shown to physically interact withC. albicans, with the bacteria exhibiting tropism for candidal hyphal filaments. This interaction enhances association levels of both microbes with the vaginal epithelial cell line VK2/E6E7. The ability of GBS to coassociate withC. albicansis dependent upon expression of the hypha-specific adhesin Als3. In turn, expression of GBS antigen I/II family adhesins (Bsp polypeptides) facilitates this coassociation and confers upon surrogateLactococcus lactisthe capacity to exhibit enhanced interactions withC. albicanson vaginal epithelium. As genitourinary tract colonization is an essential first step in the pathogenesis of GBS andC. albicans, the coassociation mechanism reported here may have important implications for the risk of disease involving both of these pathogens.

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

2021 ◽  
Author(s):  
Mallory B. Ballard ◽  
Vicki Mercado-Evans ◽  
Madelynn G. Marunde ◽  
Hephzibah Nwanosike ◽  
Jacob Zulk ◽  
...  
Keyword(s):  
Preterm Birth ◽  
Antibiotic Prophylaxis ◽  
Pregnant Women ◽  
Group B Streptococcus ◽  
Vaginal Epithelium ◽  
Content Type ◽  
Vaginal Colonization ◽  
Camp Factor ◽  
Intrapartum Antibiotic ◽  
Group B

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.

scholarly journals Triclosan Promotes Staphylococcus aureus Nasal Colonization

mBio ◽  
2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Adnan K. Syed ◽  
Sudeshna Ghosh ◽  
Nancy G. Love ◽  
Blaise R. Boles
Keyword(s):  
Staphylococcus Aureus ◽  
Risk Factor ◽  
Human Microbiome ◽  
Opportunistic Pathogen ◽  
Unintended Consequences ◽  
Nasal Colonization ◽  
Content Type ◽  
Test Population ◽  
Human Proteins ◽  
Nasal Secretions

ABSTRACT The biocide triclosan is used in many personal care products, including toothpastes, soaps, clothing, and medical equipment. Consequently, it is present as a contaminant in the environment and has been detected in some human fluids, including serum, urine, and milk. Staphylococcus aureus is an opportunistic pathogen that colonizes the noses and throats of approximately 30% of the population. Colonization with S. aureus is known to be a risk factor for several types of infection. Here we demonstrate that triclosan is commonly found in the nasal secretions of healthy adults and the presence of triclosan trends positively with nasal colonization by S. aureus. We demonstrate that triclosan can promote the binding of S. aureus to host proteins such as collagen, fibronectin, and keratin, as well as inanimate surfaces such as plastic and glass. Lastly, triclosan-exposed rats are more susceptible to nasal colonization with S. aureus. These data reveal a novel factor that influences the ability of S. aureus to bind surfaces and alters S. aureus nasal colonization. IMPORTANCE Triclosan has been used as a biocide for over 40 years, but the broader effects that it has on the human microbiome have not been investigated. We demonstrate that triclosan is present in nasal secretions of a large portion of a test population and its presence correlates with Staphylococcus aureus nasal colonization. Triclosan also promotes the binding of S. aureus to human proteins and increases the susceptibility of rats to nasal colonization by S. aureus. These findings are significant because S. aureus colonization is a known risk factor for the development of several types of infections. Our data demonstrate the unintended consequences of unregulated triclosan use and contribute to the growing body of research demonstrating inadvertent effects of triclosan on the environment and human health.

scholarly journals Streptococcus salivarius K12 Limits Group B Streptococcus Vaginal Colonization

2015 ◽  
Vol 83 (9) ◽  
pp. 3438-3444 ◽  
Author(s):  
Kathryn A. Patras ◽  
Philip A. Wescombe ◽  
Berenice Rösler ◽  
John D. Hale ◽  
John R. Tagg ◽  
...  
Keyword(s):  
Group B Streptococcus ◽  
Neonatal Infection ◽  
Antibacterial Activities ◽  
Invasive Disease ◽  
Oral Microbiota ◽  
Streptococcus Salivarius ◽  
Content Type ◽  
Vaginal Colonization ◽  
Group B

Streptococcus agalactiae(group B streptococcus [GBS]) colonizes the rectovaginal tract in 20% to 30% of women and during pregnancy can be transmitted to the newborn, causing severe invasive disease. Current routine screening and antibiotic prophylaxis have fallen short of complete prevention of GBS transmission, and GBS remains a leading cause of neonatal infection. We have investigated the ability ofStreptococcus salivarius, a predominant member of the native human oral microbiota, to control GBS colonization. Comparison of the antibacterial activities of multipleS. salivariusstrains by use of a deferred-antagonism test showed thatS. salivariusstrain K12 exhibited the broadest spectrum of activity against GBS. K12 effectively inhibited all GBS strains tested, including disease-implicated isolates from newborns and colonizing isolates from the vaginal tract of pregnant women. Inhibition was dependent on the presence of megaplasmid pSsal-K12, which encodes the bacteriocins salivaricin A and salivaricin B; however, in coculture experiments, GBS growth was impeded by K12 independently of the megaplasmid. We also demonstrated that K12 adheres to and invades human vaginal epithelial cells at levels comparable to GBS. Inhibitory activity of K12 was examinedin vivousing a mouse model of GBS vaginal colonization. Mice colonized with GBS were treated vaginally with K12. K12 administration significantly reduced GBS vaginal colonization in comparison to nontreated controls, and this effect was partially dependent on the K12 megaplasmid. Our results suggest that K12 may have potential as a preventative therapy to control GBS vaginal colonization and thereby prevent its transmission to the neonate during pregnancy.

scholarly journals Transcriptomic Analysis ofStreptococcus pyogenesColonizing the Vaginal Mucosa IdentifieshupY, an MtsR-Regulated Adhesin Involved in Heme Utilization

mBio ◽  
2019 ◽  
Vol 10 (3) ◽  
Author(s):  
Laura C. C. Cook ◽  
Nilanjana Chatterjee ◽  
Yan Li ◽  
Jorge Andrade ◽  
Michael J. Federle ◽  
...  
Keyword(s):  
Streptococcus Pyogenes ◽  
Streptococcus Agalactiae ◽  
Iron Homeostasis ◽  
Vaginal Mucosa ◽  
Heme Binding ◽  
Human Pathogen ◽  
Intracellular Iron ◽  
Essential Information ◽  
Content Type ◽  
Vaginal Colonization

ABSTRACTStreptococcus pyogenes(group A streptococcus [GAS]) is a serious human pathogen with the ability to colonize mucosal surfaces such as the nasopharynx and vaginal tract, often leading to infections such as pharyngitis and vulvovaginitis. We present genome-wide transcriptome sequencing (RNASeq) data showing the transcriptomic changes GAS undergoes during vaginal colonization. These data reveal that the regulon controlled by MtsR, a master metal regulator, is activated during vaginal colonization. This regulon includes two genes highly expressed during vaginal colonization,hupYZ. Here we show that HupY binds hemein vitro, affects intracellular concentrations of iron, and is essential for proper growth of GAS using hemoglobin or serum as the sole iron source. HupY is also important for murine vaginal colonization of both GAS and the related vaginal colonizer and pathogenStreptococcus agalactiae(group B streptococcus [GBS]). These data provide essential information on the link between metal regulation and mucosal colonization in both GAS and GBS.IMPORTANCEColonization of the host requires the ability to adapt to an environment that is often low in essential nutrients such as iron. Here we present data showing that the transcriptome of the important human pathogenStreptococcus pyogenesshows extensive remodeling duringin vivogrowth, resulting in, among many other differentially expressed genes and pathways, a significant increase in genes involved in acquiring iron from host heme. Data show that HupY, previously characterized as an adhesin in bothS. pyogenesand the related pathogenStreptococcus agalactiae, binds heme and affects intracellular iron concentrations. HupY, a protein with no known heme binding domains, represents a novel heme binding protein playing an important role in bacterial iron homeostasis as well as vaginal colonization.

scholarly journals Murine Vaginal Colonization Model for Investigating Asymptomatic Mucosal Carriage of Streptococcus pyogenes

2013 ◽  
Vol 81 (5) ◽  
pp. 1606-1617 ◽  
Author(s):  
Michael E. Watson ◽  
Hailyn V. Nielsen ◽  
Scott J. Hultgren ◽  
Michael G. Caparon
Keyword(s):  
Streptococcus Pyogenes ◽  
Critical Role ◽  
Protein A ◽  
Vaginal Fluid ◽  
Vaginal Mucosa ◽  
Lactate Oxidase ◽  
Content Type ◽  
Vaginal Colonization ◽  
Colonization Model

ABSTRACTWhile many virulence factors promotingStreptococcus pyogenesinvasive disease have been described, specific streptococcal factors and host properties influencing asymptomatic mucosal carriage remain uncertain. To address the need for a refined model of prolongedS. pyogenesasymptomatic mucosal colonization, we have adapted a preestrogenized murine vaginal colonization model forS. pyogenes. In this model, derivatives of strains HSC5, SF370, JRS4, NZ131, and MEW123 established a reproducible, asymptomatic colonization of the vaginal mucosa over a period of typically 3 to 4 weeks' duration at a relatively high colonization efficiency. Prior treatment with estradiol prolonged streptococcal colonization and was associated with reduced inflammation in the colonized vaginal epithelium as well as a decreased leukocyte presence in vaginal fluid compared to the levels of inflammation and leukocyte presence in non-estradiol-treated control mice. The utility of our model for investigatingS. pyogenesfactors contributing to mucosal carriage was verified, as a mutant with a mutation in the transcriptional regulator catabolite control protein A (CcpA) demonstrated significant impairment in vaginal colonization. An assessment ofin vivotranscriptional activity in the CcpA−strain for several known CcpA-regulated genes identified significantly elevated transcription of lactate oxidase (lctO) correlating with excessive generation of hydrogen peroxide to self-lethal levels. Deletion oflctOdid not impair colonization, but deletion oflctOin a CcpA−strain prolonged carriage, exceeding even that of the wild-type strain. Thus, while LctO is not essential for vaginal colonization, its dysregulation is deleterious, highlighting the critical role of CcpA in promoting mucosal colonization. The vaginal colonization model should prove effective for future analyses ofS. pyogenesmucosal colonization.

Electron microscope study of the microgranules in human vaginal epithelium

1978 ◽  
Vol 36 (2) ◽  
pp. 568-569
Author(s):  
A. Campos ◽  
J. Vilches ◽  
J. Gomez
Keyword(s):  
Electron Microscope ◽  
Microscope Study ◽  
Intercellular Space ◽  
Electron Microscope Study ◽  
Vaginal Epithelium ◽  
Vaginal Mucosa ◽  
Secretory Phase ◽  
Cervical Epithelium ◽  
Keratinized Epithelium ◽  
Fertile Women

Microgranules have been described with different names in keratinized and in nonkeratinized epithelium. In keratinized epithelium it seems clear that the microgranules are lamellated bodies bounded by a membrane which empty their contents into the intercellular space. Their existence in nonkeratinized epithelium is more debatable. Until now the so-called microgranules have been described in nonkeratinized bucal, lingual and cervical epithelium. In the present work we describe the morphology and nature of such structures in human vaginal epithelium.Biopsies from the midlevel of the vaginal mucosa were taken from voluntary fertile women. The specimens were divided into three groups with four vaginal specimens. The first group was obtained in the folicular phase; those of the second in the postovulatory phase and, finally, the last group corresponded to the secretory phase.

Combined stereotactic split-course fractionated gamma knife radiosurgery and conventional radiation therapy for unfavorable gliomas: a phase I study

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 37-41 ◽  
Author(s):  
William F. Regine ◽  
Roy A. Patchell ◽  
James M. Strottmann ◽  
Ali Meigooni ◽  
Michael Sanders ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Disease Progression ◽  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
External Beam Radiation ◽  
Low Grade ◽  
Beam Radiation ◽  
Content Type ◽  
Group B ◽  
Fine Print

Object. This investigation was performed to determine the tolerance and toxicities of split-course fractionated gamma knife radiosurgery (FSRS) given in combination with conventional external-beam radiation therapy (CEBRT). Methods. Eighteen patients with previously unirradiated, gliomas treated between March 1995 and January 2000 form the substrate of this report. These included 11 patients with malignant gliomas, six with low-grade gliomas, and one with a recurrent glioma. They were stratified into three groups according to tumor volume (TV). Fifteen were treated using the initial FSRS dose schedule and form the subject of this report. Group A (four patients), had TV of 5 cm3 or less (7 Gy twice pre- and twice post-CEBRT); Group B (six patients), TV greater than 5 cm3 but less than or equal to 15 cm3 (7 Gy twice pre-CEBRT and once post-CEBRT); and Group C (five patients), TV greater than 15 cm3 but less than or equal to 30 cm3 (7 Gy once pre- and once post-CEBRT). All patients received CEBRT to 59.4 Gy in 1.8-Gy fractions. Dose escalation was planned, provided the level of toxicity was acceptable. All patients were able to complete CEBRT without interruption or experiencing disease progression. Unacceptable toxicity was observed in two Grade 4/Group B patients and two Grade 4/Group C patients. Eight patients required reoperation. In three (38%) there was necrosis without evidence of tumor. Neuroimaging studies were available for evaluation in 14 patients. Two had a partial (≥ 50%) reduction in volume and nine had a minor (> 20%) reduction in size. The median follow-up period was 15 months (range 9–60 months). Six patients remained alive for 3 to 60 months. Conclusions. The imaging responses and the ability of these patients with intracranial gliomas to complete therapy without interruption or experiencing disease progression is encouraging. Excessive toxicity derived from combined FSRS and CEBRT treatment, as evaluated thus far in this study, was seen in patients with Group B and C lesions at the 7-Gy dose level. Evaluation of this novel treatment strategy with dose modification is ongoing.

scholarly journals Poor Adherence to the Screening-Based Strategy of Group B Streptococcus Despite Colonization of Pregnant Women in Greece

Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 418
Author(s):  
Maria Maroudia Berikopoulou ◽  
Aikaterini Pana ◽  
Theodota Liakopoulou-Tsitsipi ◽  
Nikos F. Vlahos ◽  
Vasiliki Papaevangelou ◽  
...  
Keyword(s):  
Risk Factors ◽  
Risk Factor ◽  
Pregnant Women ◽  
Late Onset ◽  
Group B Streptococcus ◽  
Culture Collection ◽  
Carrier Status ◽  
Cross Sectional ◽  
Screening Guidelines ◽  
Group B

Group B streptococcus (GBS) is a leading cause of serious neonatal infections. Maternal GBS colonization is associated with early- and late-onset neonatal disease (EOD/LOD). In Greece, a screening-based strategy is recommended, in which concurrent vaginal-rectal cultures should be obtained between 36 0/7 and 37 6/7 weeks’ gestation. We sought to examine the level of adherence to the GBS screening guidelines and estimate the prevalence of GBS colonization among pregnant women. Although in Greece the screening-based strategy is followed, we also examined known EOD risk factors and linked them to GBS colonization. A cross-sectional study of 604 women postpartum in three hospitals and maternity clinics was conducted. Following written informed consent, data were collected via a short self-completed questionnaire and review of patients’ records. In 34.6% of the enrolled pregnant women, no culture had been taken. Of the remaining, 12.8% had proper vaginal-rectal sample collections. The overall maternal colonization rate was 9.6%. At least one risk factor for EOD was identified in 12.6% of participants. The presence of risk factors was associated with positive cultures (p = 0.014). The rate of culture collection did not differ between women with or without an EOD risk factor. Adherence to a universal screening of pregnant women with vaginal-rectal cultures was poor. Despite probable underestimation of GBS carrier status, almost 1 in 10 participants were GBS positive during pregnancy. Screening of women with risk factors for EOD should, at least, be prioritized to achieve prevention and prompt intervention of EOD.

scholarly journals Differential Response of the Human Renal Proximal Tubular Epithelial Cell Line HK-2 to Shiga Toxin Types 1 and 2

2011 ◽  
Vol 79 (9) ◽  
pp. 3527-3540 ◽  
Author(s):  
Erin K. Lentz ◽  
Dinorah Leyva-Illades ◽  
Moo-Seung Lee ◽  
Rama P. Cherla ◽  
Vernon L. Tesh
Keyword(s):  
Epithelial Cell ◽  
Cell Line ◽  
Shiga Toxin ◽  
Renal Damage ◽  
Diarrheal Disease ◽  
Shigella Dysenteriae ◽  
Parp Cleavage ◽  
Epithelial Cell Line ◽  
Cytotoxic Action ◽  
Content Type

ABSTRACTShiga toxins (Stxs) are expressed by the enteric pathogensShigella dysenteriaeserotype 1 and certain serotypes ofEscherichia coli. Stx-producing bacteria cause bloody diarrhea with the potential to progress to acute renal failure. Stxs are potent protein synthesis inhibitors and are the primary virulence factors responsible for renal damage that may follow diarrheal disease. We explored the use of the immortalized human proximal tubule epithelial cell line HK-2 as anin vitromodel of Stx-induced renal damage. We showed that these cells express abundant membrane Gb3and are differentially susceptible to the cytotoxic action of Stxs, being more sensitive to Shiga toxin type 1 (Stx1) than to Stx2. At early time points (24 h), HK-2 cells were significantly more sensitive to Stxs than Vero cells; however, by 72 h, Vero cell monolayers were completely destroyed while some HK-2 cells survived toxin challenge, suggesting that a subpopulation of HK-2 cells are relatively toxin resistant. Fluorescently labeled Stx1 B subunits localized to both lysosomal and endoplasmic reticulum (ER) compartments in HK-2 cells, suggesting that differences in intracellular trafficking may play a role in susceptibility to Stx-mediated cytotoxicity. Although proinflammatory cytokines were not upregulated by toxin challenge, Stx2 selectively induced the expression of two chemokines, macrophage inflammatory protein-1α (MIP-1α) and MIP-1β. Stx1 and Stx2 differentially activated components of the ER stress response in HK-2 cells. Finally, we demonstrated significant poly(ADP-ribose) polymerase (PARP) cleavage after exposure to Stx1 or Stx2. However, procaspase 3 cleavage was undetectable, suggesting that HK-2 cells may undergo apoptosis in response to Stxs in a caspase 3-independent manner.

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