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Sample records for chlamydia intracellular survival

  1. Intracellular survival and persistence of Chlamydia muridarum is determined by macrophage polarization.

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    Eric Gracey

    Full Text Available Macrophages can display a number of distinct phenotypes, known collectively as polarized macrophages. The best defined of these phenotypes are the classically-activated, interferon gamma (IFNγ/LPS induced (M1 and alternatively-activated, IL-4 induced (M2 macrophages. The goal of this study is to characterize macrophage-Chlamydia interactions in the context of macrophage polarization. Here we use Chlamydia muridarum and murine bone-marrow derived macrophages to show Chlamydia does not induce M2 polarization in macrophages as a survival strategy. Unexpectedly, the infection of macrophages was silent with no upregulation of M1 macrophage-associated genes. We further demonstrate that macrophages polarized prior to infection have a differential capacity to control Chlamydia. M1 macrophages harbor up to 40-fold lower inclusion forming units (IFU than non-polarized or M2 polarized macrophages. Gene expression analysis showed an increase in 16sRNA in M2 macrophages with no change in M1 macrophages. Suppressed Chlamydia growth in M1 macrophages correlated with the induction of a bacterial gene expression profile typical of persistence as evident by increased Euo expression and decreased Omp1 and Tal expression. Observations of permissive Chlamydia growth in non-polarized and M2 macrophages and persistence in M1 macrophages were supported through electron microscopy. This work supports the importance of IFNγ in the innate immune response to Chlamydia. However, demonstration that the M1 macrophages, despite an antimicrobial signature, fail to eliminate intracellular Chlamydia supports the notion that host-pathogen co-evolution has yielded a pathogen that can evade cellular defenses against this pathogen, and persist for prolonged periods of time in the host.

  2. M2 Polarization of Human Macrophages Favors Survival of the Intracellular Pathogen Chlamydia pneumoniae.

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    Tanja Buchacher

    Full Text Available Intracellular pathogens have developed various strategies to escape immunity to enable their survival in host cells, and many bacterial pathogens preferentially reside inside macrophages, using diverse mechanisms to penetrate their defenses and to exploit their high degree of metabolic diversity and plasticity. Here, we characterized the interactions of the intracellular pathogen Chlamydia pneumoniae with polarized human macrophages. Primary human monocytes were pre-differentiated with granulocyte macrophage colony-stimulating factor or macrophage colony-stimulating factor for 7 days to yield M1-like and M2-like macrophages, which were further treated with interferon-γ and lipopolysaccharide or with interleukin-4 for 48 h to obtain fully polarized M1 and M2 macrophages. M1 and M2 cells exhibited distinct morphology with round or spindle-shaped appearance for M1 and M2, respectively, distinct surface marker profiles, as well as different cytokine and chemokine secretion. Macrophage polarization did not influence uptake of C. pneumoniae, since comparable copy numbers of chlamydial DNA were detected in M1 and M2 at 6 h post infection, but an increase in chlamydial DNA over time indicating proliferation was only observed in M2. Accordingly, 72±5% of M2 vs. 48±7% of M1 stained positive for chlamydial lipopolysaccharide, with large perinuclear inclusions in M2 and less clearly bordered inclusions for M1. Viable C. pneumoniae was present in lysates from M2, but not from M1 macrophages. The ability of M1 to restrict chlamydial replication was not observed in M1-like macrophages, since chlamydial load showed an equal increase over time for M1-like and M2-like macrophages. Our findings support the importance of macrophage polarization for the control of intracellular infection, and show that M2 are the preferred survival niche for C. pneumoniae. M1 did not allow for chlamydial proliferation, but failed to completely eliminate chlamydial infection

  3. Biology and intracellular life of chlamydia

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    Ranin Lazar

    2011-01-01

    Full Text Available Introduction. Chlamydiae are Gram-negative obligate intracellular bacteria. The developmental cycle of Chlamydiae is specific and different from other bacteria. The elementary body is the infectious form of the organism, responsible for attaching to the target host cell and promoting its entry. The reticulate body is the larger, metabolically active form of the organism, synthesizing deoxyribonucleic acid, ribonucleic acid and proteins. The elementary body and reticulate body represent evolutionary adaptations to extracellular and intracellular environments. Intracellular persistence of Chlamydia. Predisposition of Chlamydia to persist within the host cell has been recognized as a major factor in the pathogenesis of chlamydial disease. The persistence implies a long-term association between chlamydiae and their host cell that may not manifest as clinically recognizable disease. The ability of chlamydia to remain within one morphological state for a long time in response to exogenous factors suggests an innate ability of these organisms to persist intracellulary in a unique developmental form. Chlamydiae induce interferon γ and exhibit growth inhibition in their presence. While the high levels of interferon γ completely restrict the development of chlamydia, its low levels induce the development of morphologically aberrant intracellular forms. The persistent forms contain reduced levels of major outer membrane protein but high levels of chlamydial heat shock protein. Conclusion. Immunopathogenesis of chlamydial infection is one of the main focal points of current research into Chlamydia. Chlamydial infections are highly prevalent, usually asymptomatic and associated with serious sequelae. Screening programmes are the most important in the prevention of a long-term sequele.

  4. The Chlamydia psittaci genome: a comparative analysis of intracellular pathogens.

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    Anja Voigt

    Full Text Available BACKGROUND: Chlamydiaceae are a family of obligate intracellular pathogens causing a wide range of diseases in animals and humans, and facing unique evolutionary constraints not encountered by free-living prokaryotes. To investigate genomic aspects of infection, virulence and host preference we have sequenced Chlamydia psittaci, the pathogenic agent of ornithosis. RESULTS: A comparison of the genome of the avian Chlamydia psittaci isolate 6BC with the genomes of other chlamydial species, C. trachomatis, C. muridarum, C. pneumoniae, C. abortus, C. felis and C. caviae, revealed a high level of sequence conservation and synteny across taxa, with the major exception of the human pathogen C. trachomatis. Important differences manifest in the polymorphic membrane protein family specific for the Chlamydiae and in the highly variable chlamydial plasticity zone. We identified a number of psittaci-specific polymorphic membrane proteins of the G family that may be related to differences in host-range and/or virulence as compared to closely related Chlamydiaceae. We calculated non-synonymous to synonymous substitution rate ratios for pairs of orthologous genes to identify putative targets of adaptive evolution and predicted type III secreted effector proteins. CONCLUSIONS: This study is the first detailed analysis of the Chlamydia psittaci genome sequence. It provides insights in the genome architecture of C. psittaci and proposes a number of novel candidate genes mostly of yet unknown function that may be important for pathogen-host interactions.

  5. Emancipating Chlamydia: Advances in the Genetic Manipulation of a Recalcitrant Intracellular Pathogen.

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    Bastidas, Robert J; Valdivia, Raphael H

    2016-06-01

    Chlamydia species infect millions of individuals worldwide and are important etiological agents of sexually transmitted disease, infertility, and blinding trachoma. Historically, the genetic intractability of this intracellular pathogen has hindered the molecular dissection of virulence factors contributing to its pathogenesis. The obligate intracellular life cycle of Chlamydia and restrictions on the use of antibiotics as selectable markers have impeded the development of molecular tools to genetically manipulate these pathogens. However, recent developments in the field have resulted in significant gains in our ability to alter the genome of Chlamydia, which will expedite the elucidation of virulence mechanisms. In this review, we discuss the challenges affecting the development of molecular genetic tools for Chlamydia and the work that laid the foundation for recent advancements in the genetic analysis of this recalcitrant pathogen.

  6. Characterizing the intracellular distribution of metabolites in intact Chlamydia-infected cells by Raman and two-photon microscopy.

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    Szaszák, Márta; Chang, Jiun Chiun; Leng, Weinan; Rupp, Jan; Ojcius, David M; Kelley, Anne Myers

    2013-06-01

    Chlamydia species are obligate intracellular pathogens that proliferate only within infected cells. Currently, there are no known techniques or systems that can probe the spatial distribution of metabolites of interest within intact Chlamydia-infected cells. Here we investigate the ability of Raman microscopy to probe the chemical composition of different compartments (nucleus, inclusion, and cytoplasm) of Chlamydia trachomatis-infected epithelial cells. The overall intensity of the Raman spectrum is greatest in the inclusions and lowest in the cytoplasm in fixed cells. Difference spectra generated by normalizing to the intensity of the strong 1004 cm(-1) phenylalanine line show distinct differences among the three compartments. Most notably, the concentrations of adenine are greater in both the inclusions and the nucleus than in the cytoplasm, as seen by Raman microscopy. The source of the adenine was explored through a complementary approach, using two-photon microscopy imaging. Autofluorescence measurements of living, infected cells show that the adenine-containing molecules, NAD(P)H and FAD, are present mainly in the cytoplasm, suggesting that these molecules are not the source of the additional adenine signal in the nucleus and inclusions. Experiments of infected cells stained with a DNA-binding dye, Hoechst 33258, reveal that most of the DNA is present in the nucleus and the inclusions, suggesting that DNA/RNA is the main source of the additional Raman adenine signal in the nucleus and inclusions. Thus, Raman and two-photon microscopy are among the few non-invasive methods available to investigate cells infected with Chlamydia and, together, should also be useful for studying infection by other intracellular pathogens that survive within intracellular vacuoles.

  7. A zebrafish model for Chlamydia infection with the obligate intracellular pathogen Waddlia chondrophila

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    Alexander Fehr

    2016-11-01

    Full Text Available Obligate intracellular chlamydial bacteria of the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC superphylum are important pathogens of terrestrial and marine vertebrates, yet many features of their pathogenesis and host specificity are still unknown. This is particularly true for families such as the Waddliacea which, in addition to epithelia, cellular targets for nearly all Chlamydia, can infect and replicate in macrophages, an important arm of the innate immune system or in their free-living amoebal counterparts. An ideal pathogen model system should include both host and pathogen, which led us to develop the first larval zebrafish model for chlamydial infections with Waddlia chondrophila. By varying the means and sites of application, epithelial cells of the swimbladder, endothelial cells of the vasculature and phagocytosing cells of the innate immune system became preferred targets for infection in zebrafish larvae. Through the use of transgenic zebrafish, we could observe recruitment of neutrophils to the infection site and demonstrate for the first time that W. chondrophila is taken up and replicates in these phagocytic cells and not only in macrophages. Furthermore, we present evidence that myeloid differentiation factor 88 (MyD88 mediated signalling plays a role in the innate immune reaction to W. chondrophila, eventually by Toll-like receptor (TLRs recognition. Infected larvae with depleted levels of MyD88 showed a higher infection load and a lower survival rate compared to control fish. This work presents a new and potentially powerful non-mammalian experimental model to study the pathology of chlamydial virulence in vivo and opens up new possibilities for investigation of other members of the PVC superphylum.

  8. An optimal method of iron starvation of the obligate intracellular pathogen, Chlamydia trachomatis

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    Christopher C. Thompson

    2011-02-01

    Full Text Available Iron is an essential cofactor in a number of critical biochemical reactions, and as such, its acquisition, storage, and metabolism is highly regulated in most organisms. The obligate intracellular bacterium, Chlamydia trachomatis experiences a developmental arrest when iron within the host is depleted. The nature of the iron starvation response in Chlamydia is relatively uncharacterized because of the likely inefficient method of iron depletion, which currently relies on the compound deferoxamine mesylate (DFO. Inefficient induction of the iron starvation response precludes the identification of iron-regulated genes. This report evaluated DFO with another iron chelator, 2,2’-bipyridyl (Bpdl and presented a systematic comparison of the two across a range of criteria in a single-treatment time-of-infection regimen. We demonstrate that the membrane permeable Bpdl was superior to DFO in the inhibition of chlamydia development, the induction of aberrant morphology, and the induction of an iron starvation transcriptional response in both host and bacteria. Furthermore, iron starvation using Bpdl identified the periplasmic iron binding protein-encoding ytgA gene as iron- responsive. Overall, the data present a compelling argument for the use of Bpdl, rather than DFO, in future iron starvation studies of chlamydia and other intracellular bacteria.

  9. Inhibitory activity of the isoflavone biochanin a on intracellular bacteria of genus Chlamydia and initial development of a buccal formulation

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    Hanski, Leena; Genina, Natalja; Uvell, Hanna

    2014-01-01

    Given the established role of Chlamydia spp. as causative agents of both acute and chronic diseases, search for new antimicrobial agents against these intracellular bacteria is required to promote human health. Isoflavones are naturally occurring phytoestrogens, antioxidants and efflux pump...

  10. Dibenzocyclooctadiene lignans from Schisandra spp. selectively inhibit the growth of the intracellular bacteria Chlamydia pneumoniae and Chlamydia trachomatis.

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    Hakala, Elina; Hanski, Leena; Uvell, Hanna; Yrjönen, Teijo; Vuorela, Heikki; Elofsson, Mikael; Vuorela, Pia Maarit

    2015-10-01

    Lignans from Schisandra chinensis berries show various pharmacological activities, of which their antioxidative and cytoprotective properties are among the most studied ones. Here, the first report on antibacterial properties of six dibenzocyclooctadiene lignans found in Schisandra spp. is presented. The activity was shown on two related intracellular Gram-negative bacteria Chlamydia pneumoniae and Chlamydia trachomatis upon their infection in human epithelial cells. All six lignans inhibited C. pneumoniae inclusion formation and infectious progeny production. Schisandrin B inhibited C. pneumoniae inclusion formation even when administered 8 h post infection, indicating a target that occurs relatively late within the infection cycle. Upon infection, lignan-pretreated C. pneumoniae elementary bodies had impaired inclusion formation capacity. The presence and substitution pattern of methylenedioxy, methoxy and hydroxyl groups of the lignans had a profound impact on the antichlamydial activity. In addition our data suggest that the antichlamydial activity is not caused only by the antioxidative properties of the lignans. None of the compounds showed inhibition on seven other bacteria, suggesting a degree of selectivity of the antibacterial effect. Taken together, the data presented support a role of the studied lignans as interesting antichlamydial lead compounds.

  11. Invasion and intracellular survival by protozoan parasites.

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    Sibley, L David

    2011-03-01

    Intracellular parasitism has arisen only a few times during the long ancestry of protozoan parasites including in diverse groups such as microsporidians, kinetoplastids, and apicomplexans. Strategies used to gain entry differ widely from injection (e.g. microsporidians), active penetration of the host cell (e.g. Toxoplasma), recruitment of lysosomes to a plasma membrane wound (e.g. Trypanosoma cruzi), to host cell-mediated phagocytosis (e.g. Leishmania). The resulting range of intracellular niches is equally diverse ranging from cytosolic (e.g. T. cruzi) to residing within a non-fusigenic vacuole (e.g. Toxoplasma, Encephalitozoon) or a modified phagolysosome (e.g. Leishmania). These lifestyle choices influence access to nutrients, interaction with host cell signaling pathways, and detection by pathogen recognition systems. As such, intracellular life requires a repertoire of adaptations to assure entry-exit from the cell, as well as to thwart innate immune mechanisms and prevent clearance. Elucidating these pathways at the cellular and molecular level may identify key steps that can be targeted to reduce parasite survival or augment immunologic responses and thereby prevent disease.

  12. Chlamydia cell biology and pathogenesis.

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    Elwell, Cherilyn; Mirrashidi, Kathleen; Engel, Joanne

    2016-06-01

    Chlamydia spp. are important causes of human disease for which no effective vaccine exists. These obligate intracellular pathogens replicate in a specialized membrane compartment and use a large arsenal of secreted effectors to survive in the hostile intracellular environment of the host. In this Review, we summarize the progress in decoding the interactions between Chlamydia spp. and their hosts that has been made possible by recent technological advances in chlamydial proteomics and genetics. The field is now poised to decipher the molecular mechanisms that underlie the intimate interactions between Chlamydia spp. and their hosts, which will open up many exciting avenues of research for these medically important pathogens.

  13. Human female genital tract infection by the obligate intracellular bacterium Chlamydia trachomatis elicits robust Type 2 immunity.

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    Rodolfo D Vicetti Miguel

    Full Text Available While Chlamydia trachomatis infections are frequently asymptomatic, mechanisms that regulate host response to this intracellular Gram-negative bacterium remain undefined. This investigation thus used peripheral blood mononuclear cells and endometrial tissue from women with or without Chlamydia genital tract infection to better define this response. Initial genome-wide microarray analysis revealed highly elevated expression of matrix metalloproteinase 10 and other molecules characteristic of Type 2 immunity (e.g., fibrosis and wound repair in Chlamydia-infected tissue. This result was corroborated in flow cytometry and immunohistochemistry studies that showed extant upper genital tract Chlamydia infection was associated with increased co-expression of CD200 receptor and CD206 (markers of alternative macrophage activation by endometrial macrophages as well as increased expression of GATA-3 (the transcription factor regulating TH2 differentiation by endometrial CD4(+ T cells. Also among women with genital tract Chlamydia infection, peripheral CD3(+ CD4(+ and CD3(+ CD4(- cells that proliferated in response to ex vivo stimulation with inactivated chlamydial antigen secreted significantly more interleukin (IL-4 than tumor necrosis factor, interferon-γ, or IL-17; findings that repeated in T cells isolated from these same women 1 and 4 months after infection had been eradicated. Our results thus newly reveal that genital infection by an obligate intracellular bacterium induces polarization towards Type 2 immunity, including Chlamydia-specific TH2 development. Based on these findings, we now speculate that Type 2 immunity was selected by evolution as the host response to C. trachomatis in the human female genital tract to control infection and minimize immunopathological damage to vital reproductive structures.

  14. The Francisella intracellular life cycle: towards molecular mechanisms of intracellular survival and proliferation

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    Audrey eChong

    2010-12-01

    Full Text Available The tularemia-causing bacterium Francisella tularensis is a facultative intracellular organism with a complex intracellular lifecycle that ensures its survival and proliferation in a variety of mammalian cell types, including professional phagocytes. Because this cycle is essential to Francisella pathogenesis and virulence, much research has focused on deciphering the mechanisms of its intracellular survival and replication and characterizing both bacterial and host determinants of the bacterium’s intracellular cycle. Studies of various strains and host cell models have led to the consensual paradigm of Francisella as a cytosolic pathogen, but also to some controversy about its intracellular cycle. In this review, we will detail major findings that have advanced our knowledge of Francisella intracellular survival strategies and also attempt to reconcile discrepancies that exist in our molecular understanding of the Francisella-phagocyte interaction.

  15. Inhibitory activity of the isoflavone biochanin A on intracellular bacteria of genus Chlamydia and initial development of a buccal formulation.

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    Leena Hanski

    Full Text Available Given the established role of Chlamydia spp. as causative agents of both acute and chronic diseases, search for new antimicrobial agents against these intracellular bacteria is required to promote human health. Isoflavones are naturally occurring phytoestrogens, antioxidants and efflux pump inhibitors, but their therapeutic use is limited by poor water-solubility and intense first-pass metabolism. Here, we report on effects of isoflavones against C. pneumoniae and C. trachomatis and describe buccal permeability and initial formulation development for biochanin A. Biochanin A was the most potent Chlamydia growth inhibitor among the studied isoflavones, with an IC50 = 12 µM on C. pneumoniae inclusion counts and 6.5 µM on infectious progeny production, both determined by immunofluorescent staining of infected epithelial cell cultures. Encouraged by the permeation of biochanin A across porcine buccal mucosa without detectable metabolism, oromucosal film formulations were designed and prepared by a solvent casting method. The film formulations showed improved dissolution rate of biochanin A compared to powder or a physical mixture, presumably due to the solubilizing effect of hydrophilic additives and presence of biochanin A in amorphous state. In summary, biochanin A is a potent inhibitor of Chlamydia spp., and the in vitro dissolution results support the use of a buccal formulation to potentially improve its bioavailability in antichlamydial or other pharmaceutical applications.

  16. NAD+-Glycohydrolase Promotes Intracellular Survival of Group A Streptococcus.

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    Onkar Sharma

    2016-03-01

    Full Text Available A global increase in invasive infections due to group A Streptococcus (S. pyogenes or GAS has been observed since the 1980s, associated with emergence of a clonal group of strains of the M1T1 serotype. Among other virulence attributes, the M1T1 clone secretes NAD+-glycohydrolase (NADase. When GAS binds to epithelial cells in vitro, NADase is translocated into the cytosol in a process mediated by streptolysin O (SLO, and expression of these two toxins is associated with enhanced GAS intracellular survival. Because SLO is required for NADase translocation, it has been difficult to distinguish pathogenic effects of NADase from those of SLO. To resolve the effects of the two proteins, we made use of anthrax toxin as an alternative means to deliver NADase to host cells, independently of SLO. We developed a novel method for purification of enzymatically active NADase fused to an amino-terminal fragment of anthrax toxin lethal factor (LFn-NADase that exploits the avid, reversible binding of NADase to its endogenous inhibitor. LFn-NADase was translocated across a synthetic lipid bilayer in vitro in the presence of anthrax toxin protective antigen in a pH-dependent manner. Exposure of human oropharyngeal keratinocytes to LFn-NADase in the presence of protective antigen resulted in cytosolic delivery of NADase activity, inhibition of protein synthesis, and cell death, whereas a similar construct of an enzymatically inactive point mutant had no effect. Anthrax toxin-mediated delivery of NADase in an amount comparable to that observed during in vitro infection with live GAS rescued the defective intracellular survival of NADase-deficient GAS and increased the survival of SLO-deficient GAS. Confocal microscopy demonstrated that delivery of LFn-NADase prevented intracellular trafficking of NADase-deficient GAS to lysosomes. We conclude that NADase mediates cytotoxicity and promotes intracellular survival of GAS in host cells.

  17. Chlamydia trachomatis co-opts GBF1 and CERT to acquire host sphingomyelin for distinct roles during intracellular development.

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    Cherilyn A Elwell

    2011-09-01

    Full Text Available The strain designated Chlamydia trachomatis serovar that was used for experiments in this paper is Chlamydia muridarum, a species closely related to C. trachomatis (and formerly termed the Mouse Pneumonitis strain of C. trachomatis. [corrected]. The obligate intracellular pathogen Chlamydia trachomatis replicates within a membrane-bound inclusion that acquires host sphingomyelin (SM, a process that is essential for replication as well as inclusion biogenesis. Previous studies demonstrate that SM is acquired by a Brefeldin A (BFA-sensitive vesicular trafficking pathway, although paradoxically, this pathway is dispensable for bacterial replication. This finding suggests that other lipid transport mechanisms are involved in the acquisition of host SM. In this work, we interrogated the role of specific components of BFA-sensitive and BFA-insensitive lipid trafficking pathways to define their contribution in SM acquisition during infection. We found that C. trachomatis hijacks components of both vesicular and non-vesicular lipid trafficking pathways for SM acquisition but that the SM obtained from these separate pathways is being utilized by the pathogen in different ways. We show that C. trachomatis selectively co-opts only one of the three known BFA targets, GBF1, a regulator of Arf1-dependent vesicular trafficking within the early secretory pathway for vesicle-mediated SM acquisition. The Arf1/GBF1-dependent pathway of SM acquisition is essential for inclusion membrane growth and stability but is not required for bacterial replication. In contrast, we show that C. trachomatis co-opts CERT, a lipid transfer protein that is a key component in non-vesicular ER to trans-Golgi trafficking of ceramide (the precursor for SM, for C. trachomatis replication. We demonstrate that C. trachomatis recruits CERT, its ER binding partner, VAP-A, and SM synthases, SMS1 and SMS2, to the inclusion and propose that these proteins establish an on-site SM biosynthetic

  18. CRISPR System Acquisition and Evolution of an Obligate Intracellular Chlamydia-Related Bacterium

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    Bertelli, Claire; Cissé, Ousmane H.; Rusconi, Brigida; Kebbi-Beghdadi, Carole; Croxatto, Antony; Goesmann, Alexander; Collyn, François; Greub, Gilbert

    2016-01-01

    Recently, a new Chlamydia-related organism, Protochlamydia naegleriophila KNic, was discovered within a Naegleria amoeba. To decipher the mechanisms at play in the modeling of genomes from the Protochlamydia genus, we sequenced the full genome of Pr. naegleriophila, which includes a 2,885,090 bp chromosome and a 145,285 bp megaplasmid. For the first time within the Chlamydiales order, we describe the presence of a clustered regularly interspaced short palindromic repeats (CRISPR) system, the immune system of bacteria, located on the chromosome. It is composed of a small CRISPR locus comprising eight repeats and associated cas-cse genes of the subtype I-E. A CRISPR locus is also present within Chlamydia sp. Diamant, another Pr. naegleriophila strain, suggesting that the CRISPR system was acquired by a common ancestor of Pr. naegleriophila, after its divergence from Pr. amoebophila. Both nucleotide bias and comparative genomics approaches identified probable horizontal gene acquisitions within two and four genomic islands in Pr. naegleriophila KNic and Diamant genomes, respectively. The plasmid encodes an F-type conjugative system highly similar to 1) that found in the Pam100G genomic island of Pr. amoebophila UWE25 chromosome, as well as on the plasmid of Rubidus massiliensis and 2) to the three genes remaining in the chromosome of Parachlamydia acanthamoebae strains. Therefore, this conjugative system was likely acquired on an ancestral plasmid before the divergence of Parachlamydiaceae. Overall, this new complete Pr. naegleriophila genome sequence enables further investigation of the dynamic processes shaping the genomes of the family Parachlamydiaceae and the genus Protochlamydia. PMID:27516530

  19. Bordetella pertussis entry into respiratory epithelial cells and intracellular survival.

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    Lamberti, Yanina; Gorgojo, Juan; Massillo, Cintia; Rodriguez, Maria E

    2013-12-01

    Bordetella pertussis is the causative agent of pertussis, aka whooping cough. Although generally considered an extracellular pathogen, this bacterium has been found inside respiratory epithelial cells, which might represent a survival strategy inside the host. Relatively little is known, however, about the mechanism of internalization and the fate of B. pertussis inside the epithelia. We show here that B. pertussis is able to enter those cells by a mechanism dependent on microtubule assembly, lipid raft integrity, and the activation of a tyrosine-kinase-mediated signaling. Once inside the cell, a significant proportion of the intracellular bacteria evade phagolysosomal fusion and remain viable in nonacidic lysosome-associated membrane-protein-1-negative compartments. In addition, intracellular B. pertussis was found able to repopulate the extracellular environment after complete elimination of the extracellular bacteria with polymyxin B. Taken together, these data suggest that B. pertussis is able to survive within respiratory epithelial cells and by this means potentially contribute to host immune system evasion.

  20. Survival of chlamydiae in human semen prepared for artificial insemination by donor

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    Thorsen, Poul; Møller, Birger R.; Halkier-Sørensen, Lars;

    1991-01-01

    after storage when examined by enzyme immunoassay (Chlamydiazyme). When examined by cell culture, four proved chlamydia- positive before storage and two afterwards. The results indicate that testing for C. trachomatis has to be performed from the urethra of all donors of semen used for artificial...... insemination before the inoculation takes place. Udgivelsesdato: 1991...

  1. A new role of the complement system: C3 provides protection in a mouse model of lung infection with intracellular Chlamydia psittaci.

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    Jenny Bode

    Full Text Available The complement system modulates the intensity of innate and specific immunity. While it protects against infections by extracellular bacteria its role in infection with obligate intracellular bacteria, such as the avian and human pathogen Chlamydia (C. psittaci, is still unknown. In the present study, knockout mice lacking C3 and thus all main complement effector functions were intranasally infected with C. psittaci strain DC15. Clinical parameters, lung histology, and cytokine levels were determined. A subset of infections was additionally performed with mice lacking C5 or C5a receptors. Complement activation occurred before symptoms of pneumonia appeared. Mice lacking C3 were ∼100 times more susceptible to the intracellular bacteria compared to wild-type mice, with all C3(-/- mice succumbing to infection after day 9. At a low infective dose, C3(-/- mice became severely ill after an even longer delay, the kinetics suggesting a so far unknown link of complement to the adaptive, protective immune response against chlamydiae. The lethal phenotype of C3(-/- mice is not based on differences in the anti-chlamydial IgG response (which is slightly delayed as demonstrated by serum transfer experiments. In addition, during the first week of infection, the absence of C3 was associated with partial protection characterized by reduced weight loss, better clinical score and lower bacterial burden, which might be explained by a different mechanism. Lack of complement functions downstream of C5 had little effect. This study demonstrates for the first time a strong and complex influence of complement effector functions, downstream of C3 and upstream of C5, on the outcome of an infection with intracellular bacteria, such as C. psittaci.

  2. Chlamydia bacteriophages.

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    Śliwa-Dominiak, Joanna; Suszyńska, Ewa; Pawlikowska, Małgorzata; Deptuła, Wiesław

    2013-11-01

    Phages are called "good viruses" due to their ability to infect and kill pathogenic bacteria. Chlamydia are small, Gram-negative (G-) microbes that can be dangerous to human and animals. In humans, these bacteria are etiological agents of diseases such as psittacosis or respiratory tract diseases, while in animals, the infection may result in enteritis in cattle and chronic bowel diseases, as well as miscarriages in sheep. The first-known representative of chlamydiaphages was Chp1. It was discovered in Chlamydia psittaci isolates. Since then, four more species of chlamydiaphages have been identified [Chp2, Chp3, φCPG1 φCPAR39 (φCpn1) and Chp4]. All of them were shown to infect Chlamydia species. This paper described all known chlamydiaphages. They were characterised in terms of origin, host range, and their molecular structure. The review concerns the characterisation of bacteriophages that infects pathogenic and dangerous bacteria with unusual, intracellular life cycles that are pathogenic. In the era of antibiotic resistance, it is difficult to cure chlamydophilosis. Those bacteriophages can be an alternative to antibiotics, but before this happens, we need to get to know chlamydiaphages better.

  3. The role of autophagy in the intracellular survival of Campylobacter concisus

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    Jose A. Burgos-Portugal

    2014-01-01

    Full Text Available Campylobacter concisus is an emerging pathogen that has been associated with gastrointestinal diseases. Given the importance of autophagy for the elimination of intracellular bacteria and the subversion of this process by pathogenic bacteria, we investigated the role of autophagy in C. concisus intracellular survival. Gentamicin protection assays were employed to assess intracellular levels of C. concisus within Caco-2 cells, following autophagy induction and inhibition. To assess the interaction between C. concisus and autophagosomes, confocal microscopy, scanning electron microscopy, and transmission electron microscopy were employed. Expression levels of 84 genes involved in the autophagy process were measured using qPCR. Autophagy inhibition resulted in two- to four-fold increases in intracellular levels of C. concisus within Caco-2 cells, while autophagy induction resulted in a significant reduction in intracellular levels or bacterial clearance. C. concisus strains with low intracellular survival levels showed a dramatic increase in these levels upon autophagy inhibition. Confocal microscopy showed co-localization of the bacterium with autophagosomes, while transmission electron microscopy identified intracellular bacteria persisting within autophagic vesicles. Further, qPCR showed that following infection, 13 genes involved in the autophagy process were significantly regulated, and a further five showed borderline results, with an overall indication towards a dampening effect exerted by the bacterium on this process. Our data collectively indicates that while autophagy is important for the clearance of C. concisus, some strains may manipulate this process to benefit their intracellular survival.

  4. Chlamydia Exploit the Mammalian Tryptophan-Depletion Defense Strategy as a Counter-Defensive Cue to Trigger a Survival State of Persistence.

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    Carol A Bonner

    2014-02-01

    Full Text Available We previously proposed that in Chlamydiaceae rapid vegetative growth and a quiescent state of survival (persistence depend upon alternative protein translational profiles dictated by host tryptophan (Trp availability. These alternative profiles correspond, respectively, with a set of chlamydial proteins having higher-than-predicted contents of Trp (Up-Trp selection, or with another set exhibiting lower-than-predicted contents of Trp (Down-Trp selection. A comparative evaluation of Chlamydiaceae proteomes for Trp content has now been extended to a number of other taxon families within the Chlamydiales Order. At the Order level, elevated Trp content occurs for transporters of nucleotides, S-adenosylmethionine, dicarboxylate substrates, and Trp itself. For Trp and nucleotide transporters, this is even more pronounced in other chlamydiae families (Parachlamydiaceae, Waddliaceae, and Simkaniaceae due to extensive paralog expansion. This suggests that intracellular Trp availability served as an ancient survival cue for enhancement or restraint of chlamydial metabolism in the common Chlamydiales ancestor. The Chlamydiaceae Family further strengthened Up-Trp selection for proteins that function in cell division, lipopolysaccharide biosynthesis, and methyltransferase reactions. Some proteins that exhibit Up-Trp selection are uniquely present in the Chlamydiaceae, e.g., cytotoxin and the paralog families of polymorphic membrane proteins. A striking instance of Down-Trp selection in the Chlamydiaceae is the chorismate biosynthesis pathway and the connecting menaquinone pathway. The newly recognized 1,4-dihydroxy-6-napthoate pathway of menaquinone biosynthesis operates in Chlamydiaceae, whereas the classic 2-napthoate pathway is used in the other Chlamydiales families. Because of the extreme Down-Trp selection, it would appear that menaquinone biosynthesis is particularly important to the integrity of the persistent state maintained under conditions of

  5. Burkholderia cepacia complex isolates survive intracellularly without replication within acidic vacuoles of Acanthamoeba polyphaga.

    Science.gov (United States)

    Lamothe, Julie; Thyssen, Sandra; Valvano, Miguel A

    2004-12-01

    We have previously demonstrated that isolates of the Burkholderia cepacia complex can survive intracellularly in murine macrophages and in free-living Acanthamoeba. In this work, we show that the clinical isolates B. vietnamiensis strain CEP040 and B. cenocepacia H111 survived but did not replicate within vacuoles of A. polyphaga. B. cepacia-containing vacuoles accumulated the fluid phase marker Lysosensor Blue and displayed strong blue fluorescence, indicating that they had low pH. In contrast, the majority of intracellular bacteria within amoebae treated with the V-ATPse inhibitor bafilomycin A1 localized in vacuoles that did not fluoresce with Lysosensor Blue. Experiments using bacteria fluorescently labelled with chloromethylfluorescein diacetate demonstrated that intracellular bacteria remained viable for at least 24 h. In contrast, Escherichia coli did not survive within amoebae after 2 h post infection. Furthermore, intracellular B. vietnamiensis CEP040 retained green fluorescent protein within the bacterial cytoplasm, while this protein rapidly escaped from the cytosol of phagocytized heat-killed bacteria into the vacuolar lumen. Transmission electron microscopy analysis confirmed that intracellular Burkholderia cells were structurally intact. In addition, both Legionella pneumophila- and B. vietnamiensis-containing vacuoles did not accumulate cationized ferritin, a compound that localizes within the lysosome. Thus, our observations support the notion that B. cepacia complex isolates can use amoebae as a reservoir in the environment by surviving without intracellular replication within an acidic vacuole that is distinct from the lysosomal compartment.

  6. Andrographolide inhibits intracellular Chlamydia trachomatis multiplication and reduces secretion of proinflammatory mediators produced by human epithelial cells.

    Science.gov (United States)

    Hua, Ziyu; Frohlich, Kyla M; Zhang, Yan; Feng, Xiaogeng; Zhang, Jiaxing; Shen, Li

    2015-02-01

    Chlamydia trachomatis is the most common sexually transmitted bacterial disease worldwide. Untreated C. trachomatis infections may cause inflammation and ultimately damage tissues. Here, we evaluated the ability of Andrographolide (Andro), a natural diterpenoid lactone component of Andrographis paniculata, to inhibit C. trachomatis infection in cultured human cervical epithelial cells. We found that Andro exposure inhibited C. trachomatis growth in a dose- and time-dependent manner. The greatest inhibitory effect was observed when exponentially growing C. trachomatis was exposed to Andro. Electron micrographs demonstrated the accumulation of unusual, structurally deficient chlamydial organisms, correlated with a decrease in levels of OmcB expressed at the late stage of infection. Additionally, Andro significantly reduced the secretion of interleukin6, CXCL8 and interferon-γ-induced protein10 produced by host cells infected with C. trachomatis. These results indicate the efficacy of Andro to perturb C. trachomatis transition from the metabolically active reticulate body to the infectious elementary body and concurrently reduce the production of a proinflammatory mediator by epithelial cells in vitro. Further dissection of Andro's anti-Chlamydia action may provide identification of novel therapeutic targets.

  7. Intracellular survival of Clostridium chauvoei in bovine macrophages.

    Science.gov (United States)

    Pires, Prhiscylla Sadanã; Santos, Renato Lima; da Paixão, Tatiane Alves; de Oliveira Bernardes, Laura Cristina; de Macêdo, Auricélio Alves; Gonçalves, Luciana Aramuni; de Oliveira Júnior, Carlos Augusto; Silva, Rodrigo Otávio Silveira; Lobato, Francisco Carlos Faria

    2017-02-01

    Clostridium chauvoei is the etiological agent of blackleg, a severe disease of domestic ruminants, causing myonecrosis and serious toxemia with high mortality. Despite the known importance of this agent, studies evaluating its pathogenesis of blackleg are scarce, and many are based on an unproven hypothesis that states that macrophages are responsible for carrying C. chauvoei spores from the intestines to muscles in the early stages of blackleg. Therefore, the present study aimed to investigate the survival of C. chauvoei vegetative cells or spores after phagocytosis by a murine macrophage cell line (RAW 264.7) and bovine monocyte-derived macrophages and to profile inflammatory and anti-inflammatory cytokine transcripts of bovine macrophages infected with C. chauvoei vegetative cells or spores. Both vegetative cells and spores of C. chauvoei remain viable after internalization by murine and bovine macrophages. Bovine macrophages infected with vegetative cells showed a pro-inflammatory profile, while those infected with spores displayed an anti-inflammatory profile. Together, these results corroborate the classical hypothesis that macrophages may play a role in the early pathogenesis of blackleg. Moreover, this is the first study to evaluate the infection kinetics and cytokine profile of bovine monocyte-derived macrophages infected with a Clostridium species.

  8. The role of TREM-2 in internalization and intracellular survival of Brucella abortus in murine macrophages.

    Science.gov (United States)

    Wei, Pan; Lu, Qiang; Cui, Guimei; Guan, Zhenhong; Yang, Li; Sun, Changjiang; Sun, Wanchun; Peng, Qisheng

    2015-02-15

    Triggering receptor expressed on myeloid cells-2 (TREM-2) is a cell surface receptor primarily expressed on macrophages and dendritic cells. TREM-2 functions as a phagocytic receptor for bacteria as well as an inhibitor of Toll like receptors (TLR) induced inflammatory cytokines. However, the role of TREM-2 in Brucella intracellular growth remains unknown. To investigate whether TREM-2 is involved in Brucella intracellular survival, we chose bone marrow derived macrophages (BMDMs), in which TREM-2 is stably expressed, as cell model. Colony formation Units (CFUs) assay suggests that TREM-2 is involved in the internalization of Brucella abortus (B. abortus) by macrophages, while silencing of TREM-2 decreases intracellular survival of B. abortus. To further study the underlying mechanisms of TREM-2-mediated bacterial intracellular survival, we examined the activation of B. abortus-infected macrophages through determining the kinetics of activation of the three MAPKs, including ERK, JNK and p38, and measuring TNFα production in response to lipopolysaccharide (LPS) of Brucella (BrLPS) or B. abortus stimulation. Our data show that TREM-2 deficiency promotes activation of Brucella-infected macrophages. Moreover, our data also demonstrate that macrophage activation promotes killing of Brucella by enhancing nitric oxygen (NO), but not reactive oxygen species (ROS) production, macrophage apoptosis or cellular death. Taken together, these findings provide a novel interpretation of Brucella intracellular growth through inhibition of NO production produced by TREM-2-mediated activated macrophages.

  9. Synthesis of protein in host-free reticulate bodies of Chlamydia psittaci and Chlamydia trachomatis.

    OpenAIRE

    Hatch, T P; Miceli, M; Silverman, J A

    1985-01-01

    Synthesis of protein by the obligate intracellular parasitic bacteria Chlamydia psittaci (6BC) and Chlamydia trachomatis (serovar L2) isolated from host cells (host-free chlamydiae) was demonstrated for the first time. Incorporation of [35S]methionine and [35S]cysteine into trichloroacetic acid-precipitable material by reticulate bodies of chlamydiae persisted for 2 h and was dependent upon a exogenous source of ATP, an ATP-regenerating system, and potassium or sodium ions. Magnesium ions and...

  10. Chlamydia Infections

    Science.gov (United States)

    ... You can get chlamydia during oral, vaginal, or anal sex with someone who has the infection. A woman ... to prevent chlamydia is to not have vaginal, anal, or oral sex. Correct usage of latex condoms greatly reduces, but ...

  11. Intracellular trehalose improves the survival of human red blood cells by freeze-drying

    Institute of Scientific and Technical Information of China (English)

    HE Hui; LIU Baolin; HUA Zezhao; LI Chuan; WU Zhengzheng

    2007-01-01

    Freeze-drying of human red blood cells has a potential important application for blood transfusion.The aim of this study was to investigate the effects ofintracellular trehalose on the survival of red blood cells after freeze-drying and rehydration.Fresh red blood cells were incubated in trehalose solutions of various concentrations at 37℃ for 7 h following freeze-drying.Polyvinylpyrrolidone,Trehalose,sodium citrate,and human serum albumin were used as extracellular protective agents for the freeze-drying of red blood cells.The results indicated that the intracellular trehalose concentration was increased with increasing concentration of extracellular trehalose solution,and the maximum concen tration of intracellular trehalose reached 35 mmol/L.The viability of freeze-dried red blood cells increased with the increment of intracellular trehalose concentration.

  12. Intracellular survival of Staphylococcus aureus during persistent infection in the insect Tenebrio molitor.

    Science.gov (United States)

    McGonigle, John E; Purves, Joanne; Rolff, Jens

    2016-06-01

    Survival of bacteria within host cells and tissues presents a challenge to the immune systems of higher organisms. Escape from phagocytic immune cells compounds this issue, as immune cells become potential vehicles for pathogen dissemination. However, the duration of persistence within phagocytes and its contribution to pathogen load has yet to be determined. We investigate the immunological significance of intracellular persistence within the insect model Tenebrio molitor, assessing the extent, duration and location of bacterial recovery during a persistent infection. Relative abundance of Staphylococcus aureus in both intracellular and extracellular fractions was determined over 21 days, and live S. aureus were successfully recovered from both the hemolymph and within phagocytic immune cells across the entire time course. The proportion of bacteria recovered from within phagocytes also increased over time. Our results show that to accurately estimate pathogen load it is vital to account for bacteria persisting within immune cells.

  13. Swedish isolates of Vibrio cholerae enhance their survival when interacted intracellularly with Acanthamoeba castellanii

    Directory of Open Access Journals (Sweden)

    Salah Shanan

    2016-04-01

    Full Text Available Vibrio cholerae is a Gram-negative bacterium that occurs naturally in aquatic environment. Only V. cholerae O1 and V. cholerae O139 produce cholera toxin and cause cholera, other serogroups can cause gastroenteritis, open wounds infection, and septicaemia. V. cholerae O1 and V. cholerae O139 grow and survive inside Acanthamoeba castellanii. The aim of this study is to investigate the interactions of the Swedish clinical isolates V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11, and V. cholerae O160 with A. castellanii. The interaction between A. castellanii and V. cholerae strains was studied by means of amoeba cell counts, viable counts of the bacteria in the absence or presence of amoebae, and of the intracellularly growing bacteria, visualised by electron microscopy. These results show that all V. cholerae can grow and survive outside and inside the amoebae, disclosing that V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11, and V. cholerae O160 all can be considered as facultative intracellular bacteria.

  14. Swedish isolates of Vibrio cholerae enhance their survival when interacted intracellularly with Acanthamoeba castellanii.

    Science.gov (United States)

    Shanan, Salah; Bayoumi, Magdi; Saeed, Amir; Sandström, Gunnar; Abd, Hadi

    2016-01-01

    Vibrio cholerae is a Gram-negative bacterium that occurs naturally in aquatic environment. Only V. cholerae O1 and V. cholerae O139 produce cholera toxin and cause cholera, other serogroups can cause gastroenteritis, open wounds infection, and septicaemia. V. cholerae O1 and V. cholerae O139 grow and survive inside Acanthamoeba castellanii. The aim of this study is to investigate the interactions of the Swedish clinical isolates V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11, and V. cholerae O160 with A. castellanii. The interaction between A. castellanii and V. cholerae strains was studied by means of amoeba cell counts, viable counts of the bacteria in the absence or presence of amoebae, and of the intracellularly growing bacteria, visualised by electron microscopy. These results show that all V. cholerae can grow and survive outside and inside the amoebae, disclosing that V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11, and V. cholerae O160 all can be considered as facultative intracellular bacteria.

  15. The opportunistic pathogen Enterococcus faecalis resists phagosome acidification and autophagy to promote intracellular survival in macrophages.

    Science.gov (United States)

    Zou, Jun; Shankar, Nathan

    2016-06-01

    While many strains of Enterococcus faecalis have been reported to be capable of surviving within macrophages for extended periods, the exact mechanisms involved are largely unknown. In this study, we found that after phagocytosis by macrophages, enterococci-containing vacuoles resist acidification, and E. faecalis is resistant to low pH. Ultrastructural examination of the enterococci-containing vacuole by transmission electron microscopy revealed a single membrane envelope, with no evidence of the classical double-membraned autophagosomes. Western blot analysis further confirmed that E. faecalis could trigger inhibition of the production of LC3-II during infection. By employing cells transfected with RFP-LC3 plasmid and infected with GFP-labelled E. faecalis, we also observed that E. faecalis was not delivered into autophagosomes during macrophage infection. While these observations indicated no role for autophagy in elimination of intracellular E. faecalis, enhanced production of reactive oxygen species and nitric oxide were keys to this process. Stimulation of autophagy suppressed the intracellular survival of E. faecalis in macrophages in vitro and decreased the burden of E. faecalis in vivo. In summary, the results from this study offer new insights into the interaction of E. faecalis with host cells and may provide a new approach to treatment of enterococcal infections.

  16. Salmonella Engages Host MicroRNAs To Modulate SUMOylation: a New Arsenal for Intracellular Survival.

    Science.gov (United States)

    Verma, Smriti; Mohapatra, Gayatree; Ahmad, Salman Mustfa; Rana, Sarika; Jain, Swati; Khalsa, Jasneet Kaur; Srikanth, C V

    2015-09-01

    Posttranslational modifications (PTMs) can alter many fundamental properties of a protein. One or combinations of them have been known to regulate the dynamics of many cellular pathways and consequently regulate all vital processes. Understandably, pathogens have evolved sophisticated strategies to subvert these mechanisms to achieve instantaneous control over host functions. Here, we present the first report of modulation by intestinal pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) of host SUMOylation, a PTM pathway central to all fundamental cellular processes. Both in cell culture and in a mouse model, we observed that S. Typhimurium infection led to a dynamic SUMO-conjugated proteome alteration. The intracellular survival of S. Typhimurium was dependent on SUMO status as revealed by reduced infection and Salmonella-induced filaments (SIFs) in SUMO-upregulated cells. S. Typhimurium-dependent SUMO modulation was seen as a result of depletion of crucial SUMO pathway enzymes Ubc-9 and PIAS1, at both the protein and the transcript levels. Mechanistically, depletion of Ubc-9 relied on upregulation of small noncoding RNAs miR30c and miR30e during S. Typhimurium infection. This was necessary and sufficient for both down-modulation of Ubc-9 and a successful infection. Thus, we demonstrate a novel strategy of pathogen-mediated perturbation of host SUMOylation, an integral mechanism underlying S. Typhimurium infection and intracellular survival.

  17. The Salmonella effector AvrA mediates bacterial intracellular survival during infection in vivo.

    Science.gov (United States)

    Wu, Huixia; Jones, Rheinallt M; Neish, Andrew S

    2012-01-01

    The enteric pathogen Salmonella typhimurium secretes the preformed AvrA effector protein into host cells. This acetyltransferase has been shown to modulate mammalian intestinal immune and survival responses by inhibition of JNK MAPK. To study the role of this effector in natural enteric infection, we used a mouse model to compare wild-type S. typhimurium to an isogenic AvrA null Salmonella mutant. Salmonella lacking AvrA induced increased intestinal inflammation, more intense systemic cytokine responses, and increased apoptosis in epithelial cells. Increased apoptosis was also observed in extra epithelial macrophages. AvrA null-infected mice consistently showed higher bacterial burden within mucosal lymphoid tissues, spleen and liver by 5 days post infection, which indicated a more severe clinical course. To study the molecular mechanisms involved, recombinant adenoviruses expressing AvrA or mutant AvrA proteins were constructed, which showed appropriate expression and mediated the expected inhibition of JNK signalling. Cultured epithelial cells and macrophages transduced with AvrA expressing adenovirus were protected from apoptosis induced by exogenous stimuli. In conclusion, the results demonstrated that Salmonella AvrA modulates survival of infected macrophages likely via JNK suppression, and prevents macrophage death and rapid bacterial dissemination. AvrA suppression of apoptosis in infected macrophages may allow for establishment of a stable intracellular niche typical of intracellular pathogens.

  18. The β-hemolysin and intracellular survival of Streptococcus agalactiae in human macrophages.

    Directory of Open Access Journals (Sweden)

    Anubha Sagar

    Full Text Available S. agalactiae (group B streptococci, GBS is a major microbial pathogen in human neonates and causes invasive infections in pregnant women and immunocompromised individuals. The S. agalactiae β-hemolysin is regarded as an important virulence factor for the development of invasive disease. To examine the role of β-hemolysin in the interaction with professional phagocytes, the THP-1 monocytic cell line and human granulocytes were infected with a serotype Ia S. agalactiae wild type strain and its isogenic nonhemolytic mutant. We could show that the nonhemolytic mutants were able to survive in significantly higher numbers than the hemolytic wild type strain, in THP-1 macrophage-like cells and in assays with human granulocytes. Intracellular bacterial multiplication, however, could not be observed. The hemolytic wild type strain stimulated a significantly higher release of Tumor Necrosis Factor-α than the nonhemolytic mutant in THP-1 cells, while similar levels of the chemokine Interleukin-8 were induced. In order to investigate bacterial mediators of IL-8 release in this setting, purified cell wall preparations from both strains were tested and found to exert a potent proinflammatory stimulus on THP-1 cells. In conclusion, our results indicate that the β-hemolysin has a strong influence on the intracellular survival of S. agalactiae and that a tightly controlled regulation of β-hemolysin expression is required for the successful establishment of S. agalactiae in different host niches.

  19. Chlamydia infections in women

    Science.gov (United States)

    ... Alternative Names Cervicitis - chlamydia; STI - chlamydia; STD - chlamydia; Sexually transmitted - chlamydia; ... for Disease Control and Prevention. Chlamydial infections in adolescents and adults. Updated June 4, 2015. www.cdc. ...

  20. Leishmania panamensis infection and antimonial drugs modulate expression of macrophage drug transporters and metabolizing enzymes: impact on intracellular parasite survival

    Science.gov (United States)

    Gómez, Maria Adelaida; Navas, Adriana; Márquez, Ricardo; Rojas, Laura Jimena; Vargas, Deninson Alejandro; Blanco, Victor Manuel; Koren, Roni; Zilberstein, Dan; Saravia, Nancy Gore

    2014-01-01

    Objectives Treatment failure is multifactorial. Despite the importance of host cell drug transporters and metabolizing enzymes in the accumulation, distribution and metabolism of drugs targeting intracellular pathogens, their impact on the efficacy of antileishmanials is unknown. We examined the contribution of pharmacologically relevant determinants in human macrophages in the antimony-mediated killing of intracellular Leishmania panamensis and its relationship with the outcome of treatment with meglumine antimoniate. Methods Patients with cutaneous leishmaniasis who failed (n = 8) or responded (n = 8) to treatment were recruited. Gene expression profiling of pharmacological determinants in primary macrophages was evaluated by quantitative RT–PCR and correlated to the drug-mediated intracellular parasite killing. Functional validation was conducted through short hairpin RNA gene knockdown. Results Survival of L. panamensis after exposure to antimonials was significantly higher in macrophages from patients who failed treatment. Sixteen macrophage drug-response genes were modulated by infection and exposure to meglumine antimoniate. Correlation analyses of gene expression and intracellular parasite survival revealed the involvement of host cell metallothionein-2A and ABCB6 in the survival of Leishmania during exposure to antimonials. ABCB6 was functionally validated as a transporter of antimonial compounds localized in both the cell and phagolysosomal membranes of macrophages, revealing a novel mechanism of host cell-mediated regulation of intracellular drug exposure and parasite survival within phagocytes. Conclusions These results provide insight into host cell mechanisms regulating the intracellular exposure of Leishmania to antimonials and variations among individuals that impact parasite survival. Understanding of host cell determinants of intracellular pharmacokinetics/pharmacodynamics opens new avenues to improved drug efficacy for intracellular

  1. In vitro phagocytosis and intracellular survival of Campylobacter jejuni with phagocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kiehlbauch, J.A.

    1986-01-01

    In vitro phagocytosis and intracellular survival of Campylobacter jejuni was studied using three types of mononuclear phagocytes: a J774G8 peritoneal macrophage line, resident BABL/c peritoneal macrophages and human peripheral blood monocytes. In phagocytosis assays using CFU determinations, phagocytosis increased steadily over an 8 hr time period. Results obtained using a /sup 51/Cr assay indicated no consistent significant difference between phagocytosis of C. jejuni between the three mononuclear phagocytes or PMN's and that maximum infection occurred prior to 0.5 hr and maintained throughout the 4 hr assay. Further investigation of the mechanism of attachment and entry of C. jejuni revealed this process required the expenditure of energy by the phagocyte, but was not inhibited by inhibitors of microfilament functions. In addition, phagocytosis was enhanced by the presence of 20% FCS,

  2. Intracellular Uropathogenic E. coli Exploits Host Rab35 for Iron Acquisition and Survival within Urinary Bladder Cells.

    Science.gov (United States)

    Dikshit, Neha; Bist, Pradeep; Fenlon, Shannon N; Pulloor, Niyas Kudukkil; Chua, Christelle En Lin; Scidmore, Marci A; Carlyon, Jason A; Tang, Bor Luen; Chen, Swaine L; Sukumaran, Bindu

    2015-08-01

    Recurrent urinary tract infections (UTIs) caused by uropathogenic E. coli (UPEC) are common and morbid infections with limited therapeutic options. Previous studies have demonstrated that persistent intracellular infection of bladder epithelial cells (BEC) by UPEC contributes to recurrent UTI in mouse models of infection. However, the mechanisms employed by UPEC to survive within BEC are incompletely understood. In this study we aimed to understand the role of host vesicular trafficking proteins in the intracellular survival of UPEC. Using a cell culture model of intracellular UPEC infection, we found that the small GTPase Rab35 facilitates UPEC survival in UPEC-containing vacuoles (UCV) within BEC. Rab35 plays a role in endosomal recycling of transferrin receptor (TfR), the key protein responsible for transferrin-mediated cellular iron uptake. UPEC enhance the expression of both Rab35 and TfR and recruit these proteins to the UCV, thereby supplying UPEC with the essential nutrient iron. Accordingly, Rab35 or TfR depleted cells showed significantly lower intracellular iron levels and reduced ability to support UPEC survival. In the absence of Rab35, UPEC are preferentially trafficked to degradative lysosomes and killed. Furthermore, in an in vivo murine model of persistent intracellular infection, Rab35 also colocalizes with intracellular UPEC. We propose a model in which UPEC subverts two different vesicular trafficking pathways (endosomal recycling and degradative lysosomal fusion) by modulating Rab35, thereby simultaneously enhancing iron acquisition and avoiding lysosomal degradation of the UCV within bladder epithelial cells. Our findings reveal a novel survival mechanism of intracellular UPEC and suggest a potential avenue for therapeutic intervention against recurrent UTI.

  3. Intracellular Uropathogenic E. coli Exploits Host Rab35 for Iron Acquisition and Survival within Urinary Bladder Cells.

    Directory of Open Access Journals (Sweden)

    Neha Dikshit

    2015-08-01

    Full Text Available Recurrent urinary tract infections (UTIs caused by uropathogenic E. coli (UPEC are common and morbid infections with limited therapeutic options. Previous studies have demonstrated that persistent intracellular infection of bladder epithelial cells (BEC by UPEC contributes to recurrent UTI in mouse models of infection. However, the mechanisms employed by UPEC to survive within BEC are incompletely understood. In this study we aimed to understand the role of host vesicular trafficking proteins in the intracellular survival of UPEC. Using a cell culture model of intracellular UPEC infection, we found that the small GTPase Rab35 facilitates UPEC survival in UPEC-containing vacuoles (UCV within BEC. Rab35 plays a role in endosomal recycling of transferrin receptor (TfR, the key protein responsible for transferrin-mediated cellular iron uptake. UPEC enhance the expression of both Rab35 and TfR and recruit these proteins to the UCV, thereby supplying UPEC with the essential nutrient iron. Accordingly, Rab35 or TfR depleted cells showed significantly lower intracellular iron levels and reduced ability to support UPEC survival. In the absence of Rab35, UPEC are preferentially trafficked to degradative lysosomes and killed. Furthermore, in an in vivo murine model of persistent intracellular infection, Rab35 also colocalizes with intracellular UPEC. We propose a model in which UPEC subverts two different vesicular trafficking pathways (endosomal recycling and degradative lysosomal fusion by modulating Rab35, thereby simultaneously enhancing iron acquisition and avoiding lysosomal degradation of the UCV within bladder epithelial cells. Our findings reveal a novel survival mechanism of intracellular UPEC and suggest a potential avenue for therapeutic intervention against recurrent UTI.

  4. Effects of interferon gamma on Chlamydia trachomatis serovar A and L2 protein expression investigated by two-dimensional gel electrophoresis

    DEFF Research Database (Denmark)

    Shaw, A; Christiansen, Gunna; Birkelund, Svend

    1999-01-01

    Chlamydia trachomatis is an obligate intracellular bacterium causing human ocular and genital disease. The lymphokine interferon gamma (IFN-gamma) is an important immune effector exerting antimicrobial effects towards several intracellular parasites, the chlamydia included. IFN-gamma has been...

  5. Chlamydia causes fragmentation of the Golgi compartment to ensure reproduction.

    Science.gov (United States)

    Heuer, Dagmar; Rejman Lipinski, Anette; Machuy, Nikolaus; Karlas, Alexander; Wehrens, Andrea; Siedler, Frank; Brinkmann, Volker; Meyer, Thomas F

    2009-02-05

    The obligate intracellular bacterium Chlamydia trachomatis survives and replicates within a membrane-bound vacuole, termed the inclusion, which intercepts host exocytic pathways to obtain nutrients. Like many other intracellular pathogens, C. trachomatis has a marked requirement for host cell lipids, such as sphingolipids and cholesterol, produced in the endoplasmic reticulum and the Golgi apparatus. However, the mechanisms by which intracellular pathogens acquire host cell lipids are not well understood. In particular, no host cell protein responsible for transporting Golgi-derived lipids to the chlamydial inclusions has yet been identified. Here we show that Chlamydia infection in human epithelial cells induces Golgi fragmentation to generate Golgi ministacks surrounding the bacterial inclusion. Ministack formation is triggered by the proteolytic cleavage of the Golgi matrix protein golgin-84. Inhibition of golgin-84 truncation prevents Golgi fragmentation, causing a block in lipid acquisition and maturation of C. trachomatis. Golgi fragmentation by means of RNA-interference-mediated knockdown of distinct Golgi matrix proteins before infection enhances bacterial maturation. Our data functionally connect bacteria-induced golgin-84 cleavage, Golgi ministack formation, lipid acquisition and intracellular pathogen growth. We show that C. trachomatis subverts the structure and function of an entire host cell organelle for its own advantage.

  6. Kinetic studies of Candida parapsilosis phagocytosis by macrophages and detection of intracellular survival mechanisms

    Directory of Open Access Journals (Sweden)

    Renata eToth

    2014-11-01

    Full Text Available Even though the number of Candida infections due to non-albicans species like C. parapsilosis has been increasing, little is known about their pathomechanisms. Certain aspects of C. parapsilosis and host interactions have already been investigated; however we lack information about the innate cellular responses towards this species. The aim of our project was to dissect and compare the phagocytosis of C. parapsilosis to C. albicans and to another Candida species C. glabrata by murine and human macrophages by live cell video microscopy. We broke down the phagocytic process into three stages: macrophage migration, engulfment of fungal cells and host cell killing after the uptake. Our results showed increased macrophage migration towards C. parapsilosis and we observed differences during the engulfment processes when comparing the three species. The engulfment time of C. parapsilosis was comparable to that of C. albicans regardless of the pseudohypha length and spatial orientation relative to phagocytes, while the rate of host cell killing and the overall uptake regarding C. parapsilosis showed similarities mainly with C. glabrata. Furthermore, we observed difference between human and murine phagocytes in the uptake of C. parapsilosis. UV-treatment of fungal cells had varied effects on phagocytosis dependent upon which Candida strain was used. Besides statistical analysis, live cell imaging videos showed that this species similarly to the other two also has the ability to survive in host cells via the following mechanisms: yeast replication, and pseudohypha growth inside of phagocytes, exocytosis of fungal cells and also abortion of host cell mitosis following the uptake. According to our knowledge this is the first study that provides a thorough examination of C. parapsilosis phagocytosis and reports intracellular survival mechanisms associated with this species.

  7. Host Lipid Bodies as Platforms for Intracellular Survival of Protozoan Parasites.

    Science.gov (United States)

    Toledo, Daniel A M; D'Avila, Heloísa; Melo, Rossana C N

    2016-01-01

    Pathogens induce several changes in the host cell signaling and trafficking mechanisms in order to evade and manipulate the immune response. One prominent pathogen-mediated change is the formation of lipid-rich organelles, termed lipid bodies (LBs) or lipid droplets, in the host cell cytoplasm. Protozoan parasites, which contribute expressively to the burden of infectious diseases worldwide, are able to induce LB genesis in non-immune and immune cells, mainly macrophages, key players in the initial resistance to the infection. Under host-parasite interaction, LBs not only accumulate in the host cytoplasm but also relocate around and move into parasitophorous vacuoles. There is increasing evidence that protozoan parasites may target host-derived LBs either for gaining nutrients or for escaping the host immune response. Newly formed, parasite-induced LBs may serve as lipid sources for parasite growth and also produce inflammatory mediators that potentially act in the host immune response deactivation. In this mini review, we summarize current knowledge on the formation and role of host LBs as sites exploited by intracellular protozoan parasites as a strategy to maintain their own survival.

  8. Transcription of innate immunity genes and cytokine secretion by canine macrophages resistant or susceptible to intracellular survival of Leishmania infantum.

    Science.gov (United States)

    Turchetti, Andréia Pereira; da Costa, Luciana Fachini; Romão, Everton de Lima; Fujiwara, Ricardo Toshio; da Paixão, Tatiane Alves; Santos, Renato Lima

    2015-01-15

    In this study we assessed the basal transcription of genes associated with innate immunity (i.e. Nramp1, NOD1, NOD2, TLR1, TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, and TLR9) in canine monocyte-derived macrophages from Leishmania-free dogs. Additionally, secretion of cytokines (IL-10, IL-12, TNF-α and IFN-γ) and nitric oxide in culture supernatants of macrophages with higher or lower resistance to intracellular survival of Leishmania infantum was also measured. Constitutive transcription of TLR9 and NOD2 were negligible; NOD1, TLR1, and TLR7 had low levels of transcription, whereas Nramp1 and TLR2, 3, 4, 5, and 6 had higher levels of constitutive transcription in canine monocyte-derived macrophages. There were no significant differences in transcription between macrophages with higher or lower resistance to intracellular survival of L. infantum. Secretion of TNF-α was higher in more resistant macrophages (designated as resistant) at 24h after infection when compared to less resistant macrophages (designated as susceptible), as well as the secretion of IFN-γ at 72 h post infection. Secretion of IL-10 was lower in resistant macrophages at 24h after infection. No detectable production of nitric oxide was observed. Interestingly, there was a negative correlation between NOD2 transcript levels and intracellular survival of L. infantum in resistant macrophages. This study demonstrated that decreased intracellular survival of L. infantum in canine macrophages was associated with increased production of TNF-α and IFN-γ and decreased production of IL-10; and that constitutive transcription of Nramp1, TLR and NLR does not interfere in intracellular survival of L. infantum.

  9. Dextran sulfate sodium upregulates MAPK signaling for the uptake and subsequent intracellular survival of Brucella abortus in murine macrophages.

    Science.gov (United States)

    Reyes, Alisha Wehdnesday Bernardo; Arayan, Lauren Togonon; Simborio, Hannah Leah Tadeja; Hop, Huynh Tan; Min, WonGi; Lee, Hu Jang; Kim, Dong Hee; Chang, Hong Hee; Kim, Suk

    2016-02-01

    Brucellosis is one of the major zoonoses worldwide that inflicts important health problems in animal and human. Here, we demonstrated that dextran sulfate sodium (DSS) significantly increased adhesion of Brucella (B.) abortus in murine macrophages compared to untreated cells. Even without infection, Brucella uptake into macrophages increased and F-actin reorganization was induced compared with untreated cells. Furthermore, DSS increased the phosphorylation of MAPKs (ERK1/2 and p38α) in Brucella-infected, DSS-treated cells compared with the control cells. Lastly, DSS markedly increased the intracellular survival of Brucella abortus in macrophages by up to 48 h. These results suggest that DSS enhanced the adhesion and phagocytosis of B. abortus into murine macrophages by stimulating the MAPK signaling proteins phospho-ERK1/2 and p38α and that DSS increased the intracellular survival of B. abortus by inhibiting colocalization of Brucella-containing vacuoles (BCVs) with the late endosome marker LAMP-1. This study emphasizes the enhancement of the phagocytic and intracellular modulatory effects of DSS, which may suppress the innate immune system and contribute to prolonged Brucella survival and chronic infection.

  10. Relevant Genes Linked to Virulence Are Required for Salmonella Typhimurium to Survive Intracellularly in the Social Amoeba Dictyostelium discoideum.

    Science.gov (United States)

    Riquelme, Sebastián; Varas, Macarena; Valenzuela, Camila; Velozo, Paula; Chahin, Nicolás; Aguilera, Paulina; Sabag, Andrea; Labra, Bayron; Álvarez, Sergio A; Chávez, Francisco P; Santiviago, Carlos A

    2016-01-01

    The social amoeba Dictyostelium discoideum has proven to be a useful model for studying relevant aspects of the host-pathogen interaction. In this work, D. discoideum was used as a model to study the ability of Salmonella Typhimurium to survive in amoebae and to evaluate the contribution of selected genes in this process. To do this, we performed infection assays using axenic cultures of D. discoideum co-cultured with wild-type S. Typhimurium and/or defined mutant strains. Our results confirmed that wild-type S. Typhimurium is able to survive intracellularly in D. discoideum. In contrast, mutants ΔaroA and ΔwaaL are defective in intracellular survival in this amoeba. Next, we included in our study a group of mutants in genes directly linked to Salmonella virulence. Of note, mutants ΔinvA, ΔssaD, ΔclpV, and ΔphoPQ also showed an impaired ability to survive intracellularly in D. discoideum. This indicates that S. Typhimurium requires a functional biosynthetic pathway of aromatic compounds, a lipopolysaccharide containing a complete O-antigen, the type III secretion systems (T3SS) encoded in SPI-1 and SPI-2, the type VI secretion system (T6SS) encoded in SPI-6 and PhoP/PhoQ two-component system to survive in D. discoideum. To our knowledge, this is the first report on the requirement of O-antigen and T6SS in the survival of Salmonella within amoebae. In addition, mutants ΔinvA and ΔssaD were internalized in higher numbers than the wild-type strain during competitive infections, suggesting that S. Typhimurium requires the T3SS encoded in SPI-1 and SPI-2 to evade phagocytosis by D. discoideum. Altogether, these results indicate that S. Typhimurium exploits a common set of genes and molecular mechanisms to survive within amoeba and animal host cells. The use of D. discoideum as a model for host-pathogen interactions will allow us to discover the gene repertoire used by Salmonella to survive inside the amoeba and to study the cellular processes that are affected

  11. Differential Legionella spp. survival between intracellular and extracellular forms in thermal spring environments.

    Science.gov (United States)

    Kao, Po-Min; Tung, Min-Che; Hsu, Bing-Mu; Hsu, Shih-Yung; Huang, Jen-Te; Liu, Jorn-Hon; Huang, Yu-Li

    2013-05-01

    Legionella are commonly found in natural and man-made aquatic environments and are able to inhabit various species of protozoa. The relationship between the occurrence of Legionella spp. within protozoa and human legionellosis has been demonstrated; however, the proportions of intracellular and extracellular Legionella spp. in the aquatic environment were rarely reported. In this study, we developed a new method to differentiate intracellular and extracellular Legionella spp. in the aquatic environment. Water samples from three thermal spring recreational areas in southeastern Taiwan were collected and analyzed. For each water sample, concurrent measurements were performed for Legionella spp. and their free-living amoebae hosts. The overall detection rate was 32 % (16/50) for intracellular Legionella spp. and 12 % (6/50) for extracellular Legionella spp. The most prevalent host of Legionella spp. was Hartmannella vermiformis. The identified Legionella spp. differed substantially between intracellular and extracellular forms. The results showed that it may be necessary to differentiate intracellular and extracellular forms of Legionella spp.

  12. Ehrlichia chaffeensis TRP120 Activates Canonical Notch Signaling To Downregulate TLR2/4 Expression and Promote Intracellular Survival

    Directory of Open Access Journals (Sweden)

    Taslima T. Lina

    2016-07-01

    Full Text Available Ehrlichia chaffeensis preferentially targets mononuclear phagocytes and survives through a strategy of subverting innate immune defenses, but the mechanisms are unknown. We have shown E. chaffeensis type 1 secreted tandem repeat protein (TRP effectors are involved in diverse molecular pathogen-host interactions, such as the TRP120 interaction with the Notch receptor-cleaving metalloprotease ADAM17. In the present study, we demonstrate E. chaffeensis, via the TRP120 effector, activates the canonical Notch signaling pathway to promote intracellular survival. We found that nuclear translocation of the transcriptionally active Notch intracellular domain (NICD occurs in response to E. chaffeensis or recombinant TRP120, resulting in upregulation of Notch signaling pathway components and target genes notch1, adam17, hes, and hey. Significant differences in canonical Notch signaling gene expression levels (>40% were observed during early and late stages of infection, indicating activation of the Notch pathway. We linked Notch pathway activation specifically to the TRP120 effector, which directly interacts with the Notch metalloprotease ADAM17. Using pharmacological inhibitors and small interfering RNAs (siRNAs against γ-secretase enzyme, Notch transcription factor complex, Notch1, and ADAM17, we demonstrated that Notch signaling is required for ehrlichial survival. We studied the downstream effects and found that E. chaffeensis TRP120-mediated activation of the Notch pathway causes inhibition of the extracellular signal-regulated kinase 1/2 (ERK1/2 and p38 mitogen-activated protein kinase (MAPK pathways required for PU.1 and subsequent Toll-like receptor 2/4 (TLR2/4 expression. This investigation reveals a novel mechanism whereby E. chaffeensis exploits the Notch pathway to evade the host innate immune response for intracellular survival.

  13. The molecular biology and diagnostics of Chlamydia trachomatis.

    Science.gov (United States)

    Birkelund, S

    1992-08-01

    The rapid development of biotechnological methods provides the potential of dissecting the molecular structure of microorganisms. In this review the molecular biology of chlamydia is described. The genus Chlamydia contains three species C. trachomatis, C. psittaci, and C. pneumonia which all are important human pathogens. Chlamydia is obligate intracellular bacteria with a unique biphasic life cycle. The extracellularly chlamydial elementary bodies (EB) are small, metabolic inactive, infectious particles with a tight outer cell membrane. After internalization into host cells the chlamydial structure changes, they transform to reticulated bodies (RB) which become larger, metabolically active, and start to replicate. Fourtysix hrs post infection RB reorganizes to EB followed by burst of the inclusion. The structure of the EB outer membrane differs from the membrane of gram-negative bacteria since it is highly cross-linked by S-S bridges. There are, however, also similarities to gram-negative cell walls. The chlamydial major outer membrane protein, Omp1, forms pores and is closely associated with lipopolysaccharide, LPS. LPS, however, is more loosely associated with Omp1 than in other gram negative bacteria since incubation of EB with antibodies against LPS will liberate it from the chlamydial surface. Therefore the surface localized LPS may be important for chlamydial survival. OMP1 varies between the different serovar of C. trachomatis. Several very conserved regions are separated by variable domains. The variable domains are very antigenic and are localized at the surface of EB. After chlamydial internalization into the host cell transition to RB starts. Some of the early proteins are DnaK-like and groEL-like heat-shock proteins. The chlamydial DnaK-like protein is very antigenic. Patient serum samples will recognize the chlamydial DnaK-like protein. From the determined DNA sequence the amino acid sequence was determined. It was 57% homologous to the Eschrichia

  14. Clueing in on Chlamydia.

    Science.gov (United States)

    Gibbons, Wendy

    1991-01-01

    Chlamydia's role in female infertility is discussed. The relationship of this organism to other diseases such as leprosy and tuberculosis is explained. Conditions caused by Chlamydia such as Pelvic Inflammatory Disease (PID) are described. (KR)

  15. Conservation of extrusion as an exit mechanism for Chlamydia.

    Science.gov (United States)

    Zuck, Meghan; Sherrid, Ashley; Suchland, Robert; Ellis, Tisha; Hybiske, Kevin

    2016-10-01

    Chlamydiae exit via membrane-encased extrusion or through lysis of the host cell. Extrusions are novel, pathogen-containing structures that confer infectious advantages to Chlamydia, and are hypothesized to promote cell-to-cell spread, dissemination to distant tissues and facilitate immune evasion. The extrusion phenomenon has been characterized for several Chlamydia trachomatis serovars, but a thorough investigation of extrusion for additional clinically relevant C. trachomatis strains and Chlamydia species has yet to be performed. The key parameters investigated in this study were: (i) the conservation of extrusion across the Chlamydia genus, (ii) the functional requirement for candidate Chlamydia genes in extrusion formation i.e. IncA and CT228 and (iii) extrusion-mediated uptake, and consequent survival of Chlamydia inside macrophages. Inclusion morphology was characterized by live fluorescence microscopy, using an inverted GFP strategy, at early and mid-stages of infection. Enriched extrusions were used to infect bone marrow-derived macrophages, and bacterial viability was measured following macrophage engulfment. Our results demonstrate that extrusion is highly conserved across chlamydiae, including ocular, STD and LGV biovars and divergent Chlamydia species. Consequently, this exit mechanism for Chlamydia may fulfill common advantages important for pathogenesis.

  16. The stringent response of Staphylococcus aureus and its impact on survival after phagocytosis through the induction of intracellular PSMs expression.

    Directory of Open Access Journals (Sweden)

    Tobias Geiger

    Full Text Available The stringent response is initiated by rapid (pppGpp synthesis, which leads to a profound reprogramming of gene expression in most bacteria. The stringent phenotype seems to be species specific and may be mediated by fundamentally different molecular mechanisms. In Staphylococcus aureus, (pppGpp synthesis upon amino acid deprivation is achieved through the synthase domain of the bifunctional enzyme RSH (RelA/SpoT homolog. In several firmicutes, a direct link between stringent response and the CodY regulon was proposed. Wild-type strain HG001, rsh(Syn, codY and rsh(Syn, codY double mutants were analyzed by transcriptome analysis to delineate different consequences of RSH-dependent (pppGpp synthesis after induction of the stringent response by amino-acid deprivation. Under these conditions genes coding for major components of the protein synthesis machinery and nucleotide metabolism were down-regulated only in rsh positive strains. Genes which became activated upon (pppGpp induction are mostly regulated indirectly via de-repression of the GTP-responsive repressor CodY. Only seven genes, including those coding for the cytotoxic phenol-soluble modulins (PSMs, were found to be up-regulated via RSH independently of CodY. qtRT-PCR analyses of hallmark genes of the stringent response indicate that an RSH activating stringent condition is induced after uptake of S. aureus in human polymorphonuclear neutrophils (PMNs. The RSH activity in turn is crucial for intracellular expression of psms. Accordingly, rsh(Syn and rsh(Syn, codY mutants were less able to survive after phagocytosis similar to psm mutants. Intraphagosomal induction of psmα1-4 and/or psmβ1,2 could complement the survival of the rsh(Syn mutant. Thus, an active RSH synthase is required for intracellular psm expression which contributes to survival after phagocytosis.

  17. Arcobacter butzleri induces a pro-inflammatory response in THP-1 derived macrophages and has limited ability for intracellular survival.

    Science.gov (United States)

    zur Bruegge, Jennifer; Hanisch, Carlos; Einspanier, Ralf; Alter, Thomas; Gölz, Greta; Sharbati, Soroush

    2014-11-01

    Recent case reports have identified Arcobacter (A.) butzleri to be another emerging pathogen of the family Campylobacteraceae causing foodborne diseases. However, little is known about its interaction with the human immune system. As macrophages act as first defense against bacterial infections, we studied for the first time the impact of A. butzleri on human macrophages using THP-1 derived macrophages as an in vitro infection model. Our investigations considered the inflammatory response, intracellular survival and activation of caspases as potential virulence mechanisms employed by A. butzleri. Induction of IL-1α, IL-1ß, IL-6, IL-8, IL-12ß and TNFα demonstrated a pro-inflammatory response of infected macrophages towards A. butzleri. gentamycin protection assays revealed the ability of A. butzleri strains to survive and resist the hostile environment of phagocytic immune cells for up to 22 h. Moreover, initial activation of intitiator- (CASP8) as well as effector caspases (CASP3/7) was observed without the onset of DNA damage, suggesting a potential counter regulation. Intriguingly, we recognized distinct strain specific differences in invasion and survival capabilities. This suggests the existence of isolate dependent phenotype variations and different virulence potentials as known for other intestinal pathogens such as Salmonella enterica ssp.

  18. Swedish isolates of Vibrio cholerae enhance their survival when interacted intracellularly with Acanthamoeba castellanii

    OpenAIRE

    Shanan, Salah; Bayoumi, Magdi; Saeed, Amir; Sandström, Gunnar; Abd, Hadi

    2016-01-01

    Vibrio cholerae is a Gram-negative bacterium that occurs naturally in aquatic environment. Only V. cholerae O1 and V. cholerae O139 produce cholera toxin and cause cholera, other serogroups can cause gastroenteritis, open wounds infection, and septicaemia. V. cholerae O1 and V. cholerae O139 grow and survive inside Acanthamoeba castellanii. The aim of this study is to investigate the interactions of the Swedish clinical isolates V. cholerae O3, V. cholerae O4, V. cholerae O5, V. cholerae O11,...

  19. Arginase Is Essential for Survival of Leishmania donovani Promastigotes but Not Intracellular Amastigotes

    Science.gov (United States)

    Boitz, Jan M.; Gilroy, Caslin A.; Olenyik, Tamara D.; Paradis, Dustin; Perdeh, Jasmine; Dearman, Kristie; Davis, Madison J.; Yates, Phillip A.; Li, Yuexin; Riscoe, Michael K.; Ullman, Buddy

    2016-01-01

    ABSTRACT Studies of Leishmania donovani have shown that both ornithine decarboxylase and spermidine synthase, two enzymes of the polyamine biosynthetic pathway, are critical for promastigote proliferation and required for maximum infection in mice. However, the importance of arginase (ARG), the first enzyme of the polyamine pathway in Leishmania, has not been analyzed in L. donovani. To test ARG function in intact parasites, we generated Δarg null mutants in L. donovani and evaluated their ability to proliferate in vitro and trigger infections in mice. The Δarg knockout was incapable of growth in the absence of polyamine supplementation, but the auxotrophic phenotype could be bypassed by addition of either millimolar concentrations of ornithine or micromolar concentrations of putrescine or by complementation with either glycosomal or cytosolic versions of ARG. Spermidine supplementation of the medium did not circumvent the polyamine auxotrophy of the Δarg line. Although ARG was found to be essential for ornithine and polyamine synthesis, ornithine decarboxylase appeared to be the rate-limiting enzyme for polyamine production. Mouse infectivity studies revealed that the Δarg lesion reduced parasite burdens in livers by an order of magnitude but had little impact on the numbers of parasites recovered from spleens. Thus, ARG is essential for proliferation of promastigotes but not intracellular amastigotes. Coupled with previous studies, these data support a model in which L. donovani amastigotes readily salvage ornithine and have some access to host spermidine pools, while host putrescine appears to be unavailable for salvage by the parasite. PMID:27795357

  20. Increase of Intracellular Cyclic AMP by PDE4 Inhibitors Affects HepG2 Cell Cycle Progression and Survival.

    Science.gov (United States)

    Massimi, Mara; Cardarelli, Silvia; Galli, Francesca; Giardi, Maria Federica; Ragusa, Federica; Panera, Nadia; Cinque, Benedetta; Cifone, Maria Grazia; Biagioni, Stefano; Giorgi, Mauro

    2017-06-01

    Type 4 cyclic nucleotide phosphodiesterases (PDE4) are major members of a superfamily of enzymes (PDE) involved in modulation of intracellular signaling mediated by cAMP. Broadly expressed in most human tissues and present in large amounts in the liver, PDEs have in the last decade been key therapeutic targets for several inflammatory diseases. Recently, a significant body of work has underscored their involvement in different kinds of cancer, but with no attention paid to liver cancer. The present study investigated the effects of two PDE4 inhibitors, rolipram and DC-TA-46, on the growth of human hepatoma HepG2 cells. Treatment with these inhibitors caused a marked increase of intracellular cAMP level and a dose- and time-dependent effect on cell growth. The concentrations of inhibitors that halved cell proliferation to about 50% were used for cell cycle experiments. Rolipram (10 μM) and DC-TA-46 (0.5 μM) produced a decrease of cyclin expression, in particular of cyclin A, as well as an increase in p21, p27 and p53, as evaluated by Western blot analysis. Changes in the intracellular localization of cyclin D1 were also observed after treatments. In addition, both inhibitors caused apoptosis, as demonstrated by an Annexin-V cytofluorimetric assay and analysis of caspase-3/7 activity. Results demonstrated that treatment with PDE4 inhibitors affected HepG2 cell cycle and survival, suggesting that they might be useful as potential adjuvant, chemotherapeutic or chemopreventive agents in hepatocellular carcinoma. J. Cell. Biochem. 118: 1401-1411, 2017. © 2016 Wiley Periodicals, Inc.

  1. Novel overlapping coding sequences in Chlamydia trachomatis

    DEFF Research Database (Denmark)

    Jensen, Klaus Thorleif; Petersen, Lise; Falk, Søren;

    2006-01-01

    Chlamydia trachomatis is the aetiological agent of trachoma and sexually transmitted infections. The C. trachomatis genome sequence revealed an organism adapted to the intracellular habitat with a high coding ratio and a small genome consisting of 1.042-kilobase (kb) with 895 annotated protein...... of the novel genes in C. trachomatis Serovar A and Chlamydia muridarum. Several of the genes have typical gene-like and protein-like features. Furthermore, we confirm transcriptional activity from 10 of the putative genes. The combined evidence suggests that at least seven of the 15 are protein coding genes...

  2. Two novel functions of hyaluronidase from Streptococcus agalactiae are enhanced intracellular survival and inhibition of proinflammatory cytokine expression.

    Science.gov (United States)

    Wang, Zhaofei; Guo, Changming; Xu, Yannan; Liu, Guangjin; Lu, Chengping; Liu, Yongjie

    2014-06-01

    Streptococcus agalactiae is the causative agent of septicemia and meningitis in fish. Previous studies have shown that hyaluronidase (Hyl) is an important virulence factor in many Gram-positive bacteria. To investigate the role of S. agalactiae Hyl during interaction with macrophages, we inactivated the gene encoding extracellular hyaluronidase, hylB, in a clinical Hyl(+) isolate. The isogenic hylb mutant (Δhylb) displayed reduced survival in macrophages compared to the wild type and stimulated a significantly higher release of proinflammatory cytokines, such as interleukin-1β (IL-1β), IL-6, and tumor necrosis factor alpha (TNF-α), than the wild type in macrophages as well as in mice. Furthermore, only Hyl(+) strains could grow utilizing hyaluronic acid (HA) as the sole carbon source, suggesting that Hyl permits the organism to utilize host HA as an energy source. Fifty percent lethal dose (LD50) determinations in zebrafish demonstrated that the hylb mutant was highly attenuated relative to the wild-type strain. Experimental infection of BALB/c mice revealed that bacterial loads in the blood, spleen, and brain at 16 h postinfection were significantly reduced in the ΔhylB mutant compared to those in wild-type-infected mice. In conclusion, hyaluronidase has a strong influence on the intracellular survival of S. agalactiae and proinflammatory cytokine expression, suggesting that it plays a key role in S. agalactiae pathogenicity.

  3. Isolation of single Chlamydia-infected cells using laser microdissection.

    Science.gov (United States)

    Podgorny, Oleg V; Polina, Nadezhda F; Babenko, Vladislav V; Karpova, Irina Y; Kostryukova, Elena S; Govorun, Vadim M; Lazarev, Vassili N

    2015-02-01

    Chlamydia are obligate intracellular parasites of humans and animals that cause a wide range of acute and chronic infections. To elucidate the genetic basis of chlamydial parasitism, several approaches for making genetic modifications to Chlamydia have recently been reported. However, the lack of the available methods for the fast and effective selection of genetically modified bacteria restricts the application of genetic tools. We suggest the use of laser microdissection to isolate of single live Chlamydia-infected cells for the re-cultivation and whole-genome sequencing of single inclusion-derived Chlamydia. To visualise individual infected cells, we made use of the vital labelling of inclusions with the fluorescent Golgi-specific dye BODIPY® FL C5-ceramide. We demonstrated that single Chlamydia-infected cells isolated by laser microdissection and placed onto a host cell monolayer resulted in new cycles of infection. We also demonstrated the successful use of whole-genome sequencing to study the genomic variability of Chlamydia derived from a single inclusion. Our work provides the first evidence of the successful use of laser microdissection for the isolation of single live Chlamydia-infected cells, thus demonstrating that this method can help overcome the barriers to the fast and effective selection of Chlamydia.

  4. A docking study of enhanced intracellular survival protein from Mycobacterium tuberculosis with human DUSP16/MKP-7

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hye-Jin, E-mail: yoonhj@snu.ac.kr; Kim, Kyoung Hoon [Seoul National University, Seoul 151-747 (Korea, Republic of); Yang, Jin Kuk [Soongsil University, Seoul 156-743 (Korea, Republic of); Suh, Se Won [Seoul National University, Seoul 151-747 (Korea, Republic of); Seoul National University, Seoul 151-747 (Korea, Republic of); Kim, Hyunsik; Jang, Soonmin, E-mail: yoonhj@snu.ac.kr [Sejong University, Seoul 143-747 (Korea, Republic of)

    2013-11-01

    A docking study of Mtb Eis with its substrate DUSP16/MKP-7 was performed. The docking model suggests dissociation of hexameric Mtb Eis into dimers or monomers. The intracellular pathogen Mycobacterium tuberculosis (Mtb) causes tuberculosis, and one of its secreted effector proteins, called enhanced intracellular survival (Eis) protein, enhances its survival in macrophages. Mtb Eis activates JNK-specific dual-specificity protein phosphatase 16 (DUSP16)/mitogen-activated protein kinase phosphatase-7 (MKP-7) through the acetylation on Lys55, thus inactivating JNK by dephosphorylation. Based on the recently reported crystal structure of Mtb Eis, a docking model for the binding of Mtb Eis to DUSP16/MKP-7 was generated. In the docking model, the substrate helix containing Lys55 of DUSP16/MKP-7 fits nicely into the active-site cleft of Mtb Eis; the twisted β-sheet of Eis domain II embraces the substrate helix from one side. Most importantly, the side-chain of Lys55 is inserted toward acetyl-CoA and the resulting distance is 4.6 Å between the NZ atom of Lys55 and the carbonyl carbon of the acetyl group in acetyl-CoA. The binding of Mtb Eis and DUSP16/MKP-7 is maintained by strong electrostatic interactions. The active-site cleft of Mtb Eis has a negatively charged surface formed by Asp25, Glu138, Asp286, Glu395 and the terminal carboxylic group of Phe396. In contrast, DUSP16/MKP-7 contains five basic residues, Lys52, Lys55, Arg56, Arg57 and Lys62, which point toward the negatively charged surface of the active-site pocket of Mtb Eis. Thus, the current docking model suggests that the binding of DUSP16/MKP-7 to Mtb Eis should be established by charge complementarity in addition to a very favorable geometric arrangement. The suggested mode of binding requires the dissociation of the hexameric Mtb Eis into dimers or monomers. This study may be useful for future studies aiming to develop inhibitors of Mtb Eis as a new anti-tuberculosis drug candidate.

  5. The pore-forming toxin listeriolysin O is degraded by neutrophil metalloproteinase-8 and fails to mediate Listeria monocytogenes intracellular survival in neutrophils.

    Science.gov (United States)

    Arnett, Eusondia; Vadia, Stephen; Nackerman, Colleen C; Oghumu, Steve; Satoskar, Abhay R; McLeish, Kenneth R; Uriarte, Silvia M; Seveau, Stephanie

    2014-01-01

    The pore-forming toxin listeriolysin O (LLO) is a major virulence factor secreted by the facultative intracellular pathogen Listeria monocytogenes. This toxin facilitates L. monocytogenes intracellular survival in macrophages and diverse nonphagocytic cells by disrupting the internalization vesicle, releasing the bacterium into its replicative niche, the cytosol. Neutrophils are innate immune cells that play an important role in the control of infections, yet it was unknown if LLO could confer a survival advantage to L. monocytogenes in neutrophils. We report that LLO can enhance the phagocytic efficiency of human neutrophils and is unable to protect L. monocytogenes from intracellular killing. To explain the absence of L. monocytogenes survival in neutrophils, we hypothesized that neutrophil degranulation leads to the release of LLO-neutralizing molecules in the forming phagosome. In support of this, L. monocytogenes is a potent inducer of neutrophil degranulation, since its virulence factors, such as LLO, facilitate granule exocytosis. Within the first few minutes of interaction with L. monocytogenes, granules can fuse with the plasma membrane at the bacterial interaction site before closure of the phagosome. Furthermore, granule products directly degrade LLO, irreversibly inhibiting its activity. The matrix metalloproteinase-8, stored in secondary granules, was identified as an endoprotease that degrades LLO, and blocking neutrophil proteases increased L. monocytogenes intracellular survival. In conclusion, we propose that LLO degradation by matrix metalloproteinase-8 during phagocytosis protects neutrophil membranes from perforation and contributes to maintaining L. monocytogenes in a bactericidal phagosome from which it cannot escape.

  6. Roles of bovine Waddlia chondrophila and Chlamydia trachomatis in human preterm birth

    Directory of Open Access Journals (Sweden)

    D. Baud

    2015-01-01

    Full Text Available Waddlia chondrophila and Chlamydia trachomatis are intracellular bacteria associated with human miscarriage. We investigated their role in human preterm birth. Whereas presence of Chlamydia trachomatis DNA in genital tract was associated with human preterm birth, Waddlia was not, despite being present in women's genital tracts.

  7. Chlamydia trachomatis intercepts Golgi-derived sphingolipids through a Rab14-mediated transport required for bacterial development and replication.

    Directory of Open Access Journals (Sweden)

    Anahí Capmany

    Full Text Available Chlamydia trachomatis are obligate intracellular bacteria that survive and replicate in a bacterial-modified phagosome called inclusion. As other intracellular parasites, these bacteria subvert the phagocytic pathway to avoid degradation in phagolysosomes and exploit trafficking pathways to acquire both energy and nutrients essential for their survival. Rabs are host proteins that control intracellular vesicular trafficking. Rab14, a Golgi-related Rab, controls Golgi to endosomes transport. Since Chlamydia establish a close relationship with the Golgi apparatus, the recruitment and participation of Rab14 on inclusion development and bacteria growth were analyzed. Time course analysis revealed that Rab14 associated with inclusions by 10 h post infection and was maintained throughout the entire developmental cycle. The recruitment was bacterial protein synthesis-dependent but independent of microtubules and Golgi integrity. Overexpression of Rab14 dominant negative mutants delayed inclusion enlargement, and impaired bacteria replication as determined by IFU. Silencing of Rab14 by siRNA also decreased bacteria multiplication and infectivity. By electron microscopy, aberrant bacteria were observed in cells overexpressing the cytosolic negative Rab14 mutant. Our results showed that Rab14 facilitates the delivery of sphingolipids required for bacterial development and replication from the Golgi to chlamydial inclusions. Novel anti-chlamydial therapies could be developed based on the knowledge of how bacteria subvert host vesicular transport events through Rabs manipulation.

  8. Vibrio cholerae O1 strains are facultative intracellular bacteria, able to survive and multiply symbiotically inside the aquatic free-living amoeba Acanthamoeba castellanii.

    Science.gov (United States)

    Abd, Hadi; Saeed, Amir; Weintraub, Andrej; Nair, G Balakrish; Sandström, Gunnar

    2007-04-01

    Vibrio cholerae species are extracellular, waterborne, gram-negative bacteria that are overwhelmed by predators in aquatic environments. The unencapsulated serogroup V. cholerae O1 and encapsulated V. cholerae O139 cause epidemic and pandemic outbreaks of cholera. It has recently been shown that the aquatic and free-living amoeba Acanthamoeba castellanii is not a predator to V. cholerae O139; rather, V. cholerae O139 has shown an intracellular compatibility with this host. The aim of this study was to examine the ability of V. cholerae O1 classical and El Tor strains to grow and survive in A. castellanii. The interaction between A. castellanii and V. cholerae O1 strains was studied by means of amoeba cell counts and viable counts of the bacteria in the absence or presence of amoebae. The viable count of intracellularly growing bacteria was estimated by utilizing gentamicin assay. Confocal microscopy and electron microscopy were used to determine the intracellular localization of V. cholerae in A. castellanii. The results showed that V. cholerae O1 classical and El Tor strains grew and survived intracellularly in the cytoplasm of trophozoites, and that the bacteria were also found in the cysts of A. castellanii. The interaction showed a facultative intracellular behaviour of V. cholerae O1 classical and El Tor strains and a possible role of A. castellanii as an environmental host of V. cholerae species.

  9. Asymptomatic natural Chlamydia pecorum infection reduces growth rates in calves by up to 48 percent

    Science.gov (United States)

    Intracellular Chlamydia (C.) bacteria cause in cattle some acute but rare diseases such as abortion, sporadic bovine encephalomyelitis, kerato-conjunctivitis, pneumonia, enteritis and polyarthritis. Much more frequent, essentially ubiquitous worldwide, are low-level, asymptomatic chlamydial infecti...

  10. Chlamydia species-dependent differences in the growth requirement for lysosomes.

    Directory of Open Access Journals (Sweden)

    Scot P Ouellette

    Full Text Available Genome reduction is a hallmark of obligate intracellular pathogens such as Chlamydia, where adaptation to intracellular growth has resulted in the elimination of genes encoding biosynthetic enzymes. Accordingly, chlamydiae rely heavily on the host cell for nutrients yet their specific source is unclear. Interestingly, chlamydiae grow within a pathogen-defined vacuole that is in close apposition to lysosomes. Metabolically-labeled uninfected host cell proteins were provided as an exogenous nutrient source to chlamydiae-infected cells, and uptake and subsequent labeling of chlamydiae suggested lysosomal degradation as a source of amino acids for the pathogen. Indeed, Bafilomycin A1 (BafA1, an inhibitor of the vacuolar H(+/ATPase that blocks lysosomal acidification and functions, impairs the growth of C. trachomatis and C. pneumoniae, and these effects are especially profound in C. pneumoniae. BafA1 induced the marked accumulation of material within the lysosomal lumen, which was due to the inhibition of proteolytic activities, and this response inhibits chlamydiae rather than changes in lysosomal acidification per se, as cathepsin inhibitors also inhibit the growth of chlamydiae. Finally, the addition of cycloheximide, an inhibitor of eukaryotic protein synthesis, compromises the ability of lysosomal inhibitors to block chlamydial growth, suggesting chlamydiae directly access free amino acids in the host cytosol as a preferred source of these nutrients. Thus, chlamydiae co-opt the functions of lysosomes to acquire essential amino acids.

  11. Polarized Cell Division of Chlamydia trachomatis.

    Science.gov (United States)

    Abdelrahman, Yasser; Ouellette, Scot P; Belland, Robert J; Cox, John V

    2016-08-01

    Bacterial cell division predominantly occurs by a highly conserved process, termed binary fission, that requires the bacterial homologue of tubulin, FtsZ. Other mechanisms of bacterial cell division that are independent of FtsZ are rare. Although the obligate intracellular human pathogen Chlamydia trachomatis, the leading bacterial cause of sexually transmitted infections and trachoma, lacks FtsZ, it has been assumed to divide by binary fission. We show here that Chlamydia divides by a polarized cell division process similar to the budding process of a subset of the Planctomycetes that also lack FtsZ. Prior to cell division, the major outer-membrane protein of Chlamydia is restricted to one pole of the cell, and the nascent daughter cell emerges from this pole by an asymmetric expansion of the membrane. Components of the chlamydial cell division machinery accumulate at the site of polar growth prior to the initiation of asymmetric membrane expansion and inhibitors that disrupt the polarity of C. trachomatis prevent cell division. The polarized cell division of C. trachomatis is the result of the unipolar growth and FtsZ-independent fission of this coccoid organism. This mechanism of cell division has not been documented in other human bacterial pathogens suggesting the potential for developing Chlamydia-specific therapeutic treatments.

  12. DXD Motif-Dependent and -Independent Effects of the Chlamydia trachomatis Cytotoxin CT166

    Directory of Open Access Journals (Sweden)

    Miriam Bothe

    2015-02-01

    Full Text Available The Gram-negative, intracellular bacterium Chlamydia trachomatis causes acute and chronic urogenital tract infection, potentially leading to infertility and ectopic pregnancy. The only partially characterized cytotoxin CT166 of serovar D exhibits a DXD motif, which is important for the enzymatic activity of many bacterial and mammalian type A glycosyltransferases, leading to the hypothesis that CT166 possess glycosyltransferase activity. CT166-expressing HeLa cells exhibit actin reorganization, including cell rounding, which has been attributed to the inhibition of the Rho-GTPases Rac/Cdc42. Exploiting the glycosylation-sensitive Ras(27H5 antibody, we here show that CT166 induces an epitope change in Ras, resulting in inhibited ERK and PI3K signaling and delayed cell cycle progression. Consistent with the hypothesis that these effects strictly depend on the DXD motif, CT166 with the mutated DXD motif causes neither Ras-ERK inhibition nor delayed cell cycle progression. In contrast, CT166 with the mutated DXD motif is still capable of inhibiting cell migration, suggesting that CT166 with the mutated DXD motif cannot be regarded as inactive in any case. Taken together, CT166 affects various fundamental cellular processes, strongly suggesting its importance for the intracellular survival of chlamydia.

  13. DXD motif-dependent and -independent effects of the chlamydia trachomatis cytotoxin CT166.

    Science.gov (United States)

    Bothe, Miriam; Dutow, Pavel; Pich, Andreas; Genth, Harald; Klos, Andreas

    2015-02-17

    The Gram-negative, intracellular bacterium Chlamydia trachomatis causes acute and chronic urogenital tract infection, potentially leading to infertility and ectopic pregnancy. The only partially characterized cytotoxin CT166 of serovar D exhibits a DXD motif, which is important for the enzymatic activity of many bacterial and mammalian type A glycosyltransferases, leading to the hypothesis that CT166 possess glycosyltransferase activity. CT166-expressing HeLa cells exhibit actin reorganization, including cell rounding, which has been attributed to the inhibition of the Rho-GTPases Rac/Cdc42. Exploiting the glycosylation-sensitive Ras(27H5) antibody, we here show that CT166 induces an epitope change in Ras, resulting in inhibited ERK and PI3K signaling and delayed cell cycle progression. Consistent with the hypothesis that these effects strictly depend on the DXD motif, CT166 with the mutated DXD motif causes neither Ras-ERK inhibition nor delayed cell cycle progression. In contrast, CT166 with the mutated DXD motif is still capable of inhibiting cell migration, suggesting that CT166 with the mutated DXD motif cannot be regarded as inactive in any case. Taken together, CT166 affects various fundamental cellular processes, strongly suggesting its importance for the intracellular survival of chlamydia.

  14. Chlamydia - CDC Fact Sheet

    Science.gov (United States)

    ... on. Chlamydia can also cause a potentially fatal ectopic pregnancy (pregnancy that occurs outside the womb). How is ... pain, inability to get pregnant, and potentially deadly ectopic pregnancy (pregnancy outside the uterus). Men rarely have health ...

  15. Antibiotic resistance in Chlamydiae.

    Science.gov (United States)

    Sandoz, Kelsi M; Rockey, Daniel D

    2010-09-01

    There are few documented reports of antibiotic resistance in Chlamydia and no examples of natural and stable antibiotic resistance in strains collected from humans. While there are several reports of clinical isolates exhibiting resistance to antibiotics, these strains either lost their resistance phenotype in vitro, or lost viability altogether. Differences in procedures for chlamydial culture in the laboratory, low recovery rates of clinical isolates and the unknown significance of heterotypic resistance observed in culture may interfere with the recognition and interpretation of antibiotic resistance. Although antibiotic resistance has not emerged in chlamydiae pathogenic to humans, several lines of evidence suggest they are capable of expressing significant resistant phenotypes. The adept ability of chlamydiae to evolve to antibiotic resistance in vitro is demonstrated by contemporary examples of mutagenesis, recombination and genetic transformation. The isolation of tetracycline-resistant Chlamydia suis strains from pigs also emphasizes their adaptive ability to acquire antibiotic resistance genes when exposed to significant selective pressure.

  16. Chlamydia and Women

    Centers for Disease Control (CDC) Podcasts

    2009-04-02

    This women's health podcast focuses on chlamydia, its severe health consequences for women if left untreated, and the importance of annual chlamydia screening.  Created: 4/2/2009 by Office of Women’s Health (OWH) and National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 4/2/2009.

  17. Chlamydia psittaci in birds of prey, Sweden

    Directory of Open Access Journals (Sweden)

    Maria Blomqvist

    2012-05-01

    Full Text Available Background: Chlamydia psittaci is an intracellular bacterium primarily causing respiratory diseases in birds but may also be transmitted to other animals, including humans. The prevalence of the pathogen in wild birds in Sweden is largely unknown. Methods: DNA was extracted from cloacae swabs and screened for C. psittaci by using a 23S rRNA gene PCR assay. Partial 16S rRNA and ompA gene fragments were sequence determined and phylogenies were analysed by the neighbour-joining method. Results and conclusion: The C. psittaci prevalence was 1.3% in 319 Peregrine Falcons and White-tailed Sea Eagles, vulnerable top-predators in Sweden. 16S rRNA and ompA gene analysis showed that novel Chlamydia species, as well as novel C. psittaci strains, are to be found among wild birds.

  18. Significant roles played by IL-10 in Chlamydia infections.

    Science.gov (United States)

    Hakimi, Hamid; Zare-Bidaki, Mohammad; Zainodini, Nahid; Assar, Shokrollah; Arababadi, Mohammad Kazemi

    2014-06-01

    Chlamydia species are obligate intracellular parasites which cause usually asymptomatic genital tract infections and also are associated with several complications. Previous studies demonstrated that immune responses to Chlamydia species are different and the diseases will be limited to some cases. Additionally, Chlamydia species are able to modulate immune responses via regulating expression of some immune system molecules including cytokines. IL-10, as the main anti-inflammatory cytokine, plays important roles in the induction of immune-tolerance against self-antigen and also immune-homeostasis after microbe elimination. Furthermore, it has been documented that ectopic expression of IL-10 is associated with several chronic infectious diseases. Therefore, it can be hypothesized that changes in the regulation of this cytokine can be associated with infection with several species of Chlamydia and their associated complications. This review collected the recent information regarding the association and relationship of IL-10 with Chlamydia infections. Another aim of this review article is to address recent data regarding the association of genetic variations (polymorphisms) of IL-10 and Chlamydia infections.

  19. Characterization of the activity and expression of arginine decarboxylase in human and animal Chlamydia pathogens.

    Science.gov (United States)

    Bliven, Kimberly A; Fisher, Derek J; Maurelli, Anthony T

    2012-12-01

    Chlamydia pneumoniae encodes a functional arginine decarboxylase (ArgDC), AaxB, that activates upon self-cleavage and converts l-arginine to agmatine. In contrast, most Chlamydia trachomatis serovars carry a missense or nonsense mutation in aaxB abrogating activity. The G115R missense mutation was not predicted to impact AaxB functionality, making it unclear whether AaxB variations in other Chlamydia species also result in enzyme inactivation. To address the impact of gene polymorphism on functionality, we investigated the activity and production of the Chlamydia AaxB variants. Because ArgDC plays a critical role in the Escherichia coli acid stress response, we studied the ability of these Chlamydia variants to complement an E. coli ArgDC mutant in an acid shock assay. Active AaxB was detected in four additional species: Chlamydia caviae, Chlamydia pecorum, Chlamydia psittaci, and Chlamydia muridarum. Of the C. trachomatis serovars, only E appears to encode active enzyme. To determine when functional enzyme is present during the chlamydial developmental cycle, we utilized an anti-AaxB antibody to detect both uncleaved and cleaved enzyme throughout infection. Uncleaved enzyme production peaked around 20 h postinfection, with optimal cleavage around 44 h. While the role ArgDC plays in Chlamydia survival or virulence is unclear, our data suggest a niche-specific function.

  20. Seroprevalence and Risk Factors of Chlamydia Infection in Domestic Rabbits (Oryctolagus cuniculus in China

    Directory of Open Access Journals (Sweden)

    Xiaoting Ni

    2015-01-01

    Full Text Available Chlamydia spp. are obligate intracellular bacteria distributed all over the world, known to cause various forms of diseases in animals and humans. In the present study, a serological survey was conducted to detect the seroprevalence and risk factors associated with rabbit chlamydiosis in northeast China, including Liaoning province, Jilin province, Heilongjiang province, and Inner Mongolia Autonomous Region. Antibodies to Chlamydia were determined by indirect hemagglutination assay (IHA. The overall seroprevalence was estimated at 17.88% in total of 800 blood samples. The Chlamydia seroprevalence varied in domestic rabbits from different factors, and genders of domestic rabbits were considered as major risk factors associated with Chlamydia infection. Our study revealed a widespread and high prevalence of Chlamydia infection in domestic rabbits in northeast China, with higher exposure risk in female domestic rabbits. These findings suggested the potential importance of domestic rabbits in the transmission of zoonotic Chlamydia infection, and thus Chlamydia should be taken into consideration in diagnosing rabbit diseases. To our knowledge, there is no report of Chlamydia infection in domestic rabbits in China and the results extend the host range for Chlamydia, which has important implications for public health and the local economy.

  1. Seroprevalence and Risk Factors of Chlamydia Infection in Domestic Rabbits (Oryctolagus cuniculus) in China.

    Science.gov (United States)

    Ni, Xiaoting; Qin, Siyuan; Lou, Zhilong; Ning, Hongrui; Sun, Xiaolin

    2015-01-01

    Chlamydia spp. are obligate intracellular bacteria distributed all over the world, known to cause various forms of diseases in animals and humans. In the present study, a serological survey was conducted to detect the seroprevalence and risk factors associated with rabbit chlamydiosis in northeast China, including Liaoning province, Jilin province, Heilongjiang province, and Inner Mongolia Autonomous Region. Antibodies to Chlamydia were determined by indirect hemagglutination assay (IHA). The overall seroprevalence was estimated at 17.88% in total of 800 blood samples. The Chlamydia seroprevalence varied in domestic rabbits from different factors, and genders of domestic rabbits were considered as major risk factors associated with Chlamydia infection. Our study revealed a widespread and high prevalence of Chlamydia infection in domestic rabbits in northeast China, with higher exposure risk in female domestic rabbits. These findings suggested the potential importance of domestic rabbits in the transmission of zoonotic Chlamydia infection, and thus Chlamydia should be taken into consideration in diagnosing rabbit diseases. To our knowledge, there is no report of Chlamydia infection in domestic rabbits in China and the results extend the host range for Chlamydia, which has important implications for public health and the local economy.

  2. Chlamydia genomics: providing novel insights into chlamydial biology.

    Science.gov (United States)

    Bachmann, Nathan L; Polkinghorne, Adam; Timms, Peter

    2014-08-01

    Chlamydiaceae are obligate intracellular pathogens that have successfully evolved to colonize a diverse range of hosts. There are currently 11 described species of Chlamydia, most of which have a significant impact on the health of humans or animals. Expanding chlamydial genome sequence information has revolutionized our understanding of chlamydial biology, including aspects of their unique lifecycle, host-pathogen interactions, and genetic differences between Chlamydia strains associated with different host and tissue tropisms. This review summarizes the major highlights of chlamydial genomics and reflects on the considerable impact these have had on understanding the biology of chlamydial pathogens and the changing nature of genomics tools in the 'post-genomics' era.

  3. Evolution, phylogeny, and molecular epidemiology of Chlamydia.

    Science.gov (United States)

    Nunes, Alexandra; Gomes, João P

    2014-04-01

    The Chlamydiaceae are a family of obligate intracellular bacteria characterized by a unique biphasic developmental cycle. It encompasses the single genus Chlamydia, which involves nine species that affect a wide range of vertebral hosts, causing infections with serious impact on human health (mainly due to Chlamydia trachomatis infections) and on farming and veterinary industries. It is believed that Chlamydiales originated ∼700mya, whereas C. trachomatis likely split from the other Chlamydiaceae during the last 6mya. This corresponds to the emergence of modern human lineages, with the first descriptions of chlamydial infections as ancient as four millennia. Chlamydiaceae have undergone a massive genome reduction, on behalf of the deletional bias "use it or lose it", stabilizing at 1-1.2Mb and keeping a striking genome synteny. Their phylogeny reveals species segregation according to biological properties, with huge differences in terms of host range, tissue tropism, and disease outcomes. Genome differences rely on the occurrence of mutations in the >700 orthologous genes, as well as on events of recombination, gene loss, inversion, and paralogous expansion, affecting both a hypervariable region named the plasticity zone, and genes essentially encoding polymorphic and transmembrane head membrane proteins, type III secretion effectors and some metabolic pathways. Procedures for molecular typing are still not consensual but have allowed the knowledge of molecular epidemiology patterns for some species as well as the identification of outbreaks and emergence of successful clones for C. trachomatis. This manuscript intends to provide a comprehensive review on the evolution, phylogeny, and molecular epidemiology of Chlamydia.

  4. Existence of two groups of Staphylococcus aureus strains isolated from bovine mastitis based on biofilm formation, intracellular survival, capsular profile and agr-typing.

    Science.gov (United States)

    Bardiau, Marjorie; Caplin, Jonathan; Detilleux, Johann; Graber, Hans; Moroni, Paolo; Taminiau, Bernard; Mainil, Jacques G

    2016-03-15

    Staphylococcus (S.) aureus is recognised worldwide as an important pathogen causing contagious acute and chronic bovine mastitis. Chronic mastitis account for a significant part of all bovine cases and represent an important economic problem for dairy producers. Several properties (biofilm formation, intracellular survival, capsular expression and group agr) are thought to be associated with this chronic status. In a previous study, we found the existence of two groups of strains based on the association of these features. The aim of the present work was to confirm on a large international and non-related collection of strains the existence of these clusters and to associate them with case history records. In addition, the genomes of eight strains were sequenced to study the genomic differences between strains of each cluster. The results confirmed the existence of both groups based on capsular typing, intracellular survival and agr-typing: strains cap8-positive, belonging to agr group II, showing a low invasion rate and strains cap5-positive, belonging to agr group I, showing a high invasion rate. None of the two clusters were associated with the chronic status of the cow. When comparing the genomes of strains belonging to both clusters, the genes specific to the group "cap5-agrI" would suggest that these strains are better adapted to live in hostile environment. The existence of these two groups is highly important as they may represent two clusters that are adapted differently to the host and/or the surrounding environment.

  5. Adhesion, invasion, intracellular survival and cytotoxic activity of strains of Aeromonas spp. in HEp-2, Caco-2 and T-84 cell lines.

    Science.gov (United States)

    dos Santos, Paula Azevedo; Pereira, Ana Claudia Machado; Ferreira, Andréa Fonseca; de Mattos Alves, Maria Angélica; Rosa, Ana Cláudia Paula; Freitas-Almeida, Angela Corrêa

    2015-05-01

    The genus Aeromonas contains important pathogen for both humans and other animals, being responsible for the etiology of intestinal and extraintestinal diseases. The pathology caused by these bacteria involves several virulence factors, such as the ability to produce toxins, adhesion and invasion. The properties conferred by these factors have been extensively studied in experiments of interaction between bacterial strains and cell culture. We evaluate the interaction of eight Aeromonas spp. strains, previously isolated from human faeces, food and water with HEp-2, Caco-2 and T-84 cell lines. Cytotoxic effects, the pattern of adhesion, invasive capacity and intracellular survival were analyzed. The results showed that Aeromonas strains were adherent to three cells lines in 6 h of incubation, displaying the aggregative adherence pattern. Among eight strains studied, 50% produced cytotoxic effects on HEp-2 cells, while none of the strains produced cytotoxic effects on Caco-2 and T-84 cells at 48 h. This study demonstrated that subsets of Aeromonas isolated from different sources were able to invade intestinal (T-84, Caco-2) and epithelial (HEp-2) cell lines cultivated in vitro surviving in intracellular environments up to 72 h. Finally, our results support the pathogenic potential of Aeromonas, especially those of food and clinical sources.

  6. The molecular biology and diagnostics of Chlamydia trachomatis

    DEFF Research Database (Denmark)

    Birkelund, Svend

    1992-01-01

    The rapid development of biotechnological methods provides the potential of dissecting the molecular structure of microorganisms. In this review the molecular biology of chlamydia is described. The genus Chlamydia contains three species C. trachomatis, C. psittaci, and C. pneumonia which all...... are important human pathogens. Chlamydia is obligate intracellular bacteria with a unique biphasic life cycle. The extracellularly chlamydial elementary bodies (EB) are small, metabolic inactive, infectious particles with a tight outer cell membrane. After internalization into host cells the chlamydial...... since it is highly cross-linked by S-S bridges. There are, however, also similarities to gram-negative cell walls. The chlamydial major outer membrane protein, Omp1, forms pores and is closely associated with lipopolysaccharide, LPS. LPS, however, is more loosely associated with Omp1 than in other gram...

  7. Transcriptomic Analysis of Yersinia enterocolitica Biovar 1B Infecting Murine Macrophages Reveals New Mechanisms of Extracellular and Intracellular Survival.

    Science.gov (United States)

    Bent, Zachary W; Poorey, Kunal; Brazel, David M; LaBauve, Annette E; Sinha, Anupama; Curtis, Deanna J; House, Samantha E; Tew, Karen E; Hamblin, Rachelle Y; Williams, Kelly P; Branda, Steven S; Young, Glenn M; Meagher, Robert J

    2015-07-01

    Yersinia enterocolitica is typically considered an extracellular pathogen; however, during the course of an infection, a significant number of bacteria are stably maintained within host cell vacuoles. Little is known about this population and the role it plays during an infection. To address this question and to elucidate the spatially and temporally dynamic gene expression patterns of Y. enterocolitica biovar 1B through the course of an in vitro infection, transcriptome sequencing and differential gene expression analysis of bacteria infecting murine macrophage cells were performed under four distinct conditions. Bacteria were first grown in a nutrient-rich medium at 26 °C to establish a baseline of gene expression that is unrelated to infection. The transcriptomes of these bacteria were then compared to bacteria grown in a conditioned cell culture medium at 37 °C to identify genes that were differentially expressed in response to the increased temperature and medium but not in response to host cells. Infections were then performed, and the transcriptomes of bacteria found on the extracellular surface and intracellular compartments were analyzed individually. The upregulated genes revealed potential roles for a variety of systems in promoting intracellular virulence, including the Ysa type III secretion system, the Yts2 type II secretion system, and the Tad pilus. It was further determined that mutants of each of these systems had decreased virulence while infecting macrophages. Overall, these results reveal the complete set of genes expressed by Y. enterocolitica in response to infection and provide the groundwork for future virulence studies.

  8. High seroprevalence of Chlamydia infection in sows in Hunan province, subtropical China.

    Science.gov (United States)

    Zhang, Xiao-Xuan; Li, Run-Cheng; Liu, Guo-Hua; Cong, Wei; Song, Hui-Qun; Yu, Xing-Long; Zhu, Xing-Quan

    2014-04-01

    Chlamydia spp. are Gram-negative obligate intracellular bacteria, which are responsible for significant public health problems in humans and have major economic impact on animals. In the present study, the seroprevalence of Chlamydia infection in sows in Hunan province, subtropical China, was examined using indirect hemagglutination assay (IHA). Antibodies to Chlamydia were detected in 747 of 1,191 (62.7%, 95% CI 60-65.5) serum samples (IHA titer ≥ 1:16). The Chlamydia seroprevalence ranged from 35% (95% CI 25.7-44.4) to 77.1% (95% CI 69.1-85.2) among different regions in Hunan province, and the differences were statistically significant (P Chlamydia infection in sows was higher in summer (75.7%, 95% CI 71.3-80) and spring (63.2%, 95% CI 57.5-68.8) than in autumn (56.9%, 95% CI 51.5-62.3) and winter (48.6%, 95% CI 42-55.3), and the differences were statistically significant (P Chlamydia infection in sows in Hunan province, subtropical China, which poses a potential risk for human infection with Chlamydia in this province. This is the first report of Chlamydia seroprevalence in sows over the last two decades in Hunan province, subtropical China.

  9. Seroprevalence and Risk Factors of Chlamydia Infection in Domestic Rabbits (Oryctolagus cuniculus) in China

    OpenAIRE

    Xiaoting Ni; Siyuan Qin; Zhilong Lou; Hongrui Ning; Xiaolin Sun

    2015-01-01

    Chlamydia spp. are obligate intracellular bacteria distributed all over the world, known to cause various forms of diseases in animals and humans. In the present study, a serological survey was conducted to detect the seroprevalence and risk factors associated with rabbit chlamydiosis in northeast China, including Liaoning province, Jilin province, Heilongjiang province, and Inner Mongolia Autonomous Region. Antibodies to Chlamydia were determined by indirect hemagglutination assay (IHA). The...

  10. Universal stress protein Rv2624c alters abundance of arginine and enhances intracellular survival by ATP binding in mycobacteria

    Science.gov (United States)

    Jia, Qiong; Hu, Xinling; Shi, Dawei; Zhang, Yan; Sun, Meihao; Wang, Jianwei; Mi, Kaixia; Zhu, Guofeng

    2016-01-01

    The universal stress protein family is a family of stress-induced proteins. Universal stress proteins affect latency and antibiotic resistance in mycobacteria. Here, we showed that Mycobacterium smegmatis overexpressing M. tuberculosis universal stress protein Rv2624c exhibits increased survival in human monocyte THP-1 cells. Transcriptome analysis suggested that Rv2624c affects histidine metabolism, and arginine and proline metabolism. LC-MS/MS analysis showed that Rv2624c affects the abundance of arginine, a modulator of both mycobacteria and infected THP-1 cells. Biochemical analysis showed that Rv2624c is a nucleotide-binding universal stress protein, and an Rv2624c mutant incapable of binding ATP abrogated the growth advantage in THP-1 cells. Rv2624c may therefore modulate metabolic pathways in an ATP-dependent manner, changing the abundance of arginine and thus increasing survival in THP-1 cells. PMID:27762279

  11. [Chlamydia trachomatis proteasome protein as one of the significant pathogenicity factors of exciter].

    Science.gov (United States)

    Davydov, D Iu; Zigangirova, N A

    2014-01-01

    Sex-related infections are a global problem. Such infections may lead to acute or chronic diseases. Chlamydia trachomatis is a dangerous and widespread pathogenicity factor that is not sensitive to conventional drugs and has no obvious symptoms. Protein CPAF is leading factor of pathogenesis. This protein inhibits the signaling pathways of host cell and supports long survival of the pathogen in the host cell. The goal of this work was to review general properties of the proteasome Chlamydia protein CPAF, its functions, and role in pathology. The role of protein CPAF in the anti-chlamydia immune reaction is discussed. The prospects of the development of promising anti-chlamydia vaccine, as well as new effective anti-chlamydia drugs are also discussed.

  12. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Chlamydia Psittaci Vaccine (Feline... VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.71 Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia. Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia, shall...

  13. Depletion of autophagy-related genes ATG3 and ATG5 in Tenebrio molitor leads to decreased survivability against an intracellular pathogen, Listeria monocytogenes.

    Science.gov (United States)

    Tindwa, Hamisi; Jo, Yong Hun; Patnaik, Bharat Bhusan; Noh, Mi Young; Kim, Dong Hyun; Kim, Iksoo; Han, Yeon Soo; Lee, Yong Seok; Lee, Bok Luel; Kim, Nam Jung

    2015-01-01

    Macroautophagy (autophagy) is an evolutionarily conserved catabolic process involved in physiological and developmental processes including cell survival, death, and innate immunity. Homologues of most of 36 originally discovered autophagy-related (ATG) genes in yeast have been characterized in higher eukaryotes including insects. In this study, the homologues of ATG3 (TmATG3) and ATG5 (TmATG5) were isolated from the coleopteran beetle, Tenebrio molitor by expressed sequence tag and RNAseq approaches. The cDNA of TmATG3 and TmATG5 comprise open-reading frame sizes of 963 and 792 bp encoding polypeptides of 320 and 263 amino acid residues, respectively. TmATG3 and TmATG5 mRNA are expressed in all developmental stages, and mainly in fat body and hemocytes of larvae. TmATG3 and TmATG5 showed an overall sequence identity of 58-95% to other insect Atg proteins. There exist clear one-to-one orthologs of TmATG3 and TmATG5 in Tribolium and that they clustered together in the gene tree. Depletion of TmATG3 and TmATG5 by RNA interference led to a significant reduction in survival ability of T. molitor larvae against an intracellular pathogen, Listeria monocytogenes. Six days post-Listeria challenge, the survival rate in the dsEGFP-injected (where EGFP is enhanced green fluorescent protein) control larvae was significantly higher (55%) compared to 4 and 3% for TmATG3 and TmATG5 double-stranded RNA injected larvae, respectively. These data suggested that TmATG3 and TmATG5 may play putative role in mediating autophagy-based clearance of Listeria in T. molitor model.

  14. Recovery of an environmental Chlamydia strain from activated sludge by co-cultivation with Acanthamoeba sp.

    Science.gov (United States)

    Collingro, Astrid; Poppert, Sven; Heinz, Eva; Schmitz-Esser, Stephan; Essig, Andreas; Schweikert, Michael; Wagner, Michael; Horn, Matthias

    2005-01-01

    Chlamydiae are a unique group of obligate intracellular bacteria comprising important pathogens of vertebrates as well as symbionts of free-living amoebae. Although there is ample molecular evidence for a huge diversity and wide distribution of chlamydiae in nature, environmental chlamydiae are currently represented by only few isolates. This paper reports the recovery of a novel environmental chlamydia strain from activated sludge by co-cultivation with Acanthamoeba sp. The recovered environmental chlamydia strain UV-7 showed the characteristic morphology of chlamydial developmental stages as revealed by electron microscopy and was identified as a new member of the family Parachlamydiaceae (98.7 % 16S rRNA sequence similarity to Parachlamydia acanthamoebae). Infection studies suggested that Parachlamydia sp. UV-7 is not confined to amoeba hosts but is also able to invade mammalian cells. These findings outline a new straightforward approach to retrieving environmental chlamydiae from nature without prior, tedious isolation and cultivation of their natural host cells, and lend further support to suggested implications of environmental chlamydiae for public health.

  15. 衣原体调控宿主细胞凋亡的机制研究进展%Advances in chlamydia regulated apoptosis in host cells

    Institute of Scientific and Technical Information of China (English)

    冉欧; 陆春雪(综述); 吴移谋(审校)

    2014-01-01

    衣原体是一类专性细胞内寄生的原核微生物,常引起性传播疾病、失明和肺炎等疾病。衣原体可能已经进化出调控宿主细胞的若干机制,通过改变宿主细胞蛋白位置,干扰宿主细胞凋亡信号通路等来抑制细胞凋亡,维持其自身的存活,核转录因子NF-κB也涉及到衣原体感染细胞凋亡抑制;衣原体可以经半胱氨酸蛋白酶依赖途径等机制诱导细胞凋亡,进而感染邻近细胞。%Chlamydia is an obligate intracellular prokaryotic microorganism , which usually results in sexually transmitted diseases, blind disease, and pneumonia disease, etc.Chlamydia may have developed some elaborate mechanisms regula-ting the infected cells .Chlamydia inhibits cell apoptosis and maintains its own survival via changing the position of host cell protein and interfering cell apoptosic signaling pathways .Nuclear transcription factor kappaB ( NF-κB) is also associated with apoptosic inhibition of chlamydia infection.The pathogen can induce apoptosis by caspase-depended pathway and other mechanisms to invade the neighboring cells .

  16. Uncivil engineers: Chlamydia, Salmonella and Shigella alter cytoskeleton architecture to invade epithelial cells.

    Science.gov (United States)

    Dunn, Joe Dan; Valdivia, Raphael H

    2010-08-01

    The obligate intracellular bacterial pathogen Chlamydia trachomatis is a major cause of blindness and sexually transmitted diseases. Like the enteric pathogens Salmonella and Shigella, Chlamydia injects effector proteins into epithelial cells to initiate extensive remodeling of the actin cytoskeleton at the bacterial attachment site, which culminates in the engulfment of the bacterium by plasma membrane extensions. Numerous Salmonella and Shigella effectors promote this remodeling by activating Rho GTPases and tyrosine kinase signaling cascades and by directly manipulating actin dynamics. Recent studies indicate that similar host-cell alterations occur during Chlamydia invasion, but few effectors are known. The identification of additional Chlamydia effectors and the elucidation of their modes of function are critical steps towards an understanding of how this clinically important pathogen breaches epithelial surfaces and causes infection.

  17. Genetic differences in the Chlamydia trachomatis tryptophan synthase alpha-subunit can explain variations in serovar pathogenesis

    DEFF Research Database (Denmark)

    Shaw, A C; Christiansen, G; Roepstorff, P;

    2000-01-01

    The human pathogen Chlamydia trachomatis is an obligate intracellular bacterium, characterized by a developmental cycle that alternates between the infectious, extracellular elementary bodies and intracellular, metabolically active reticulate bodies. The cellular immune effector interferon gamma ......A activity, thus elucidating a possible molecular mechanism behind variations in the pathogenesis of C. trachomatis serovars....

  18. Chlamydia induces anchorage independence in 3T3 cells and detrimental cytological defects in an infection model.

    Directory of Open Access Journals (Sweden)

    Andrea E Knowlton

    Full Text Available Chlamydia are gram negative, obligate intracellular bacterial organisms with different species causing a multitude of infections in both humans and animals. Chlamydia trachomatis is the causative agent of the sexually transmitted infection (STI Chlamydia, the most commonly acquired bacterial STI in the United States. Chlamydial infections have also been epidemiologically linked to cervical cancer in women co-infected with the human papillomavirus (HPV. We have previously shown chlamydial infection results in centrosome amplification and multipolar spindle formation leading to chromosomal instability. Many studies indicate that centrosome abnormalities, spindle defects, and chromosome segregation errors can lead to cell transformation. We hypothesize that the presence of these defects within infected dividing cells identifies a possible mechanism for Chlamydia as a cofactor in cervical cancer formation. Here we demonstrate that infection with Chlamydia trachomatis is able to transform 3T3 cells in soft agar resulting in anchorage independence and increased colony formation. Additionally, we show for the first time Chlamydia infects actively replicating cells in vivo. Infection of mice with Chlamydia results in significantly increased cell proliferation within the cervix, and in evidence of cervical dysplasia. Confocal examination of these infected tissues also revealed elements of chlamydial induced chromosome instability. These results contribute to a growing body of data implicating a role for Chlamydia in cervical cancer development and suggest a possible molecular mechanism for this effect.

  19. A review of Chlamydia pneumoniae and atherosclerosis

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal; Fasting, H; Henneberg, E W;

    1999-01-01

    Chlamydia pneumoniae is a Gram-negative obligate intracellular bacterium that causes acute upper and lower respiratory infections. Its distribution is worldwide. Seroepidemiological studies have shown an association between C. pneumoniae and atherosclerosis, and the risk of acute myocardial infar...... individuals who are or are not infected with C. pneumoniae. The latter are needed in order to clarify the impact of the presence of C. pneumoniae and to avoid indiscriminate use of antimicrobials....... of viable organisms. However, the pathogenicity is unknown, and the significance of detecting the organism is unresolved. In two minor controlled clinical trials, patients with ischaemic heart disease were randomised into antibiotic-treated and placebo groups. Both trials showed a significant reduction...

  20. Comparative proteome analysis of Chlamydia trachomatis serovar A, D and L2

    DEFF Research Database (Denmark)

    Shaw, Allan C; Gevaert, Kris; Demol, Hans

    2002-01-01

    Chlamydia trachomatis represents a group of human pathogenic obligate intracellular and gram-negative bacteria. The genome of C. trachomatis D comprises 894 open reading frames (ORFs). In this study the global expression of genes in C. trachomatis A, D and L2, which are responsible for different ...

  1. Identification and characterization of a novel Chlamydia trachomatis reticulate body protein

    DEFF Research Database (Denmark)

    Shaw, Allan C; Larsen, Martin Røssel; Roepstorff, Peter;

    2002-01-01

    The genome of the obligate intracellular bacterium Chlamydia trachomatis comprises 894 genes predicted by computer-based analysis. As part of a large-scale proteome analysis of C. trachomatis, a small abundant protein encoded by a previously unrecognized novel 204-bp open reading frame was identi...

  2. Functional genomics of intracellular bacteria.

    Science.gov (United States)

    de Barsy, Marie; Greub, Gilbert

    2013-07-01

    During the genomic era, a large amount of whole-genome sequences accumulated, which identified many hypothetical proteins of unknown function. Rapidly, functional genomics, which is the research domain that assign a function to a given gene product, has thus been developed. Functional genomics of intracellular pathogenic bacteria exhibit specific peculiarities due to the fastidious growth of most of these intracellular micro-organisms, due to the close interaction with the host cell, due to the risk of contamination of experiments with host cell proteins and, for some strict intracellular bacteria such as Chlamydia, due to the absence of simple genetic system to manipulate the bacterial genome. To identify virulence factors of intracellular pathogenic bacteria, functional genomics often rely on bioinformatic analyses compared with model organisms such as Escherichia coli and Bacillus subtilis. The use of heterologous expression is another common approach. Given the intracellular lifestyle and the many effectors that are used by the intracellular bacteria to corrupt host cell functions, functional genomics is also often targeting the identification of new effectors such as those of the T4SS of Brucella and Legionella.

  3. Detection of Chlamydia in the peripheral blood cells of normal donors using in vitro culture, immunofluorescence microscopy and flow cytometry techniques

    Directory of Open Access Journals (Sweden)

    Andrzejewski Chester

    2006-02-01

    Full Text Available Abstract Background Chlamydia trachomatis (Ct and Chlamydia pneumoniae (Cp are medically significant infectious agents associated with various chronic human pathologies. Nevertheless, specific roles in disease progression or initiation are incompletely defined. Both pathogens infect established cell lines in vitro and polymerase chain reaction (PCR has detected Chlamydia DNA in various clinical specimens as well as in normal donor peripheral blood monocytes (PBMC. However, Chlamydia infection of other blood cell types, quantification of Chlamydia infected cells in peripheral blood and transmission of this infection in vitro have not been examined. Methods Cp specific titers were assessed for sera from 459 normal human donor blood (NBD samples. Isolated white blood cells (WBC were assayed by in vitro culture to evaluate infection transmission of blood cell borne chlamydiae. Smears of fresh blood samples (FB were dual immunostained for microscopic identification of Chlamydia-infected cell types and aliquots also assessed using Flow Cytometry (FC. Results ELISA demonstrated that 219 (47.7% of the NBD samples exhibit elevated anti-Cp antibody titers. Imunofluorescence microscopy of smears demonstrated 113 (24.6% of samples contained intracellular Chlamydia and monoclonals to specific CD markers showed that in vivo infection of neutrophil and eosinophil/basophil cells as well as monocytes occurs. In vitro culture established WBCs of 114 (24.8% of the NBD samples harbored infectious chlamydiae, clinically a potentially source of transmission, FC demonstrated both Chlamydia infected and uninfected cells can be readily identified and quantified. Conclusion NBD can harbor infected neutrophils, eosinophil/basophils and monocytes. The chlamydiae are infectious in vitro, and both total, and cell type specific Chlamydia carriage is quantifiable by FC.

  4. Serological and nested PCR survey to determine the occurrence of Chlamydia infections in the Polish cattle population.

    Science.gov (United States)

    Szymańska-Czerwińska, Monika; Niemczuk, Krzysztof; Galińska, Elżbieta Monika

    2013-01-01

    Chlamydia spp. is an obligate intracellular agent that causes chlamydiosis in animals and humans. The aim of the presented study was to investigate the prevalence of Chlamydia infection in the Polish cattle population, both asymptomatic and having reproductive disorders. The study was performed on 4,475 serum samples collected from 16 Polish provinces at the turn of 2009-2011. The samples (3,419 from asymptomatic cattle and 1,056 from cattle with reproductive disorders) were tested by complement fixation test (CFT). Moreover, 160 and 201 samples of biological materials from both groups of cattle, respectively, were tested by nested PCR. The results obtained for two tested groups were compared by χ2 (ch-squared) test, both individually for each region (province), and generally for the whole country. The CFT results showed that the seroprevalence of Chlamydia spp. infections in the asymptomatic cattle population was 4.15%, while in the cattle with reproductive disorders--7.20%. There was a significant statistical difference between compared groups for whole country, but there were no significant differences for individual provinces. The results of PCR showed that Chlamydia spp. was present in both asymptomatic cattle and cattle having reproductive disorders. The nested PCR study confirmed the presence of Chlamydia abortus and Chlamydia suis in the tested samples. The presented study indicates that infections with Chlamydia spp. are present among Polish cattle, but the percentage of infected animals is not high.

  5. Status of vaccine research and development of vaccines for Chlamydia trachomatis infection.

    Science.gov (United States)

    Poston, Taylor B; Gottlieb, Sami L; Darville, Toni

    2017-01-19

    Genital infection with Chlamydia trachomatis, a gram-negative obligate intracellular bacterium, is the most common bacterial sexually transmitted infection globally. Ascension of chlamydial infection to the female upper genital tract can cause acute pelvic inflammatory disease, tubal factor infertility, ectopic pregnancy, and chronic pelvic pain. Shortcomings of current chlamydia control strategies, especially for low- and middle-income countries, highlight the need for an effective vaccine. Evidence from animal models, human epidemiological studies, and early trachoma vaccine trials suggest that a C. trachomatis vaccine is feasible. Vaccine development for genital chlamydial infection has been in the preclinical phase of testing for many years, but the first Phase I trials of chlamydial vaccine candidates are underway, and scientific advances hold promise for additional candidates to enter clinical evaluation in the coming years. We describe the clinical and public health need for a C. trachomatis vaccine, provide an overview of Chlamydia vaccine development efforts, and summarize current vaccine candidates in the development pipeline.

  6. Chlamydia trachomatis: avances y perspectivas

    OpenAIRE

    Ostos Ortiz, Olga Lucia; Sánchez, Ruth Mélida

    2003-01-01

    La Chlamydia es una bacteria Gram negativa, no móvil, de vida parasitaria intracelular obligada porque carece de habilidad para sintetizar ATP, son parásitos energéticos, no tienen vida libre y colonizan el citoplasma de las células susceptibles

  7. The Proteome of the Isolated Chlamydia trachomatis Containing Vacuole Reveals a Complex Trafficking Platform Enriched for Retromer Components.

    Directory of Open Access Journals (Sweden)

    Lukas Aeberhard

    2015-06-01

    Full Text Available Chlamydia trachomatis is an important human pathogen that replicates inside the infected host cell in a unique vacuole, the inclusion. The formation of this intracellular bacterial niche is essential for productive Chlamydia infections. Despite its importance for Chlamydia biology, a holistic view on the protein composition of the inclusion, including its membrane, is currently missing. Here we describe the host cell-derived proteome of isolated C. trachomatis inclusions by quantitative proteomics. Computational analysis indicated that the inclusion is a complex intracellular trafficking platform that interacts with host cells' antero- and retrograde trafficking pathways. Furthermore, the inclusion is highly enriched for sorting nexins of the SNX-BAR retromer, a complex essential for retrograde trafficking. Functional studies showed that in particular, SNX5 controls the C. trachomatis infection and that retrograde trafficking is essential for infectious progeny formation. In summary, these findings suggest that C. trachomatis hijacks retrograde pathways for effective infection.

  8. Differential Translocation of Host Cellular Materials into the Chlamydia trachomatis Inclusion Lumen during Chemical Fixation.

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    Marcela Kokes

    Full Text Available Chlamydia trachomatis manipulates host cellular pathways to ensure its proliferation and survival. Translocation of host materials into the pathogenic vacuole (termed 'inclusion' may facilitate nutrient acquisition and various organelles have been observed within the inclusion, including lipid droplets, peroxisomes, multivesicular body components, and membranes of the endoplasmic reticulum (ER. However, few of these processes have been documented in living cells. Here, we survey the localization of a broad panel of subcellular elements and find ER, mitochondria, and inclusion membranes within the inclusion lumen of fixed cells. However, we see little evidence of intraluminal localization of these organelles in live inclusions. Using time-lapse video microscopy we document ER marker translocation into the inclusion lumen during chemical fixation. These intra-inclusion ER elements resist a variety of post-fixation manipulations and are detectable via immunofluorescence microscopy. We speculate that the localization of a subset of organelles may be exaggerated during fixation. Finally, we find similar structures within the pathogenic vacuole of Coxiella burnetti infected cells, suggesting that fixation-induced translocation of cellular materials may occur into the vacuole of a range of intracellular pathogens.

  9. Screening on urogenital Chlamydia trachomatis

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    Busse, Reinhard

    2005-12-01

    Full Text Available Introduction: Around 92 million urogenital infections are caused yearly by Chlamydia trachomatis worldwide [1]. The overall incidence of sexually transmitted diseases is increasing, as shown by the increases in the number of reported cases of syphilis and gonorrhea [2]. Chlamydia trachomatis infections are associated with various serious diseases in women, men and newborns, which could be, at least partially, avoided by means of early diagnosis and therapy. The Federal Joint Committee - responsible for decision-making concerning the benefit package of the German Social Health Insurance - has publicly announced the starting of deliberations on the issue of screening for Chlamydia trachomatis. Research Questions: The leading question to be answered is whether screening for Chlamydia trachomatis should be included in the German benefit basket. The aim of this report is to provide a summary of the available evidence concerning the issue of screening for Chlamydia trachomatis. Methods: The summary of published scientific evidence, including HTA reports, systematic reviews, guidelines and primary research is represented. The synthesis follows the structure given by the criteria of Wilson and Jungner [3] for the introduction of screening in a population: relevance of the condition, availability of an adequate test, effectiveness of screening, acceptance of the programme, and economical issues. A literature search was conducted for each aspect of the synthesis and the evidence has been summarised in evidence tables. Results: We identified five HTA reports from three European agencies [4], [5], [6], [7] and one from the USA [8]. In addition, we identified four guidelines from Northamerica [9], [10], [11], [12] and one from Europe [13]. A total of 56 primary research publications were included: relevance of the disease (n=26, availability of test (n=1, effectiveness of screening (n=11, acceptance of the programme (n=11, economical issues (n=7. Discussion

  10. Characterization of a secreted Chlamydia protease

    DEFF Research Database (Denmark)

    Shaw, Allan C; Vandahl, Brian; Larsen, Martin Røssel;

    2002-01-01

    Chlamydia. Several secretion candidates from Chlamydia trachomatis D and Chlamydia pneumoniae were detected by this method. Two protein spots were identified among the candidates. These represent fragments of the 'chlamydial protease- or proteasome-like activity factor' (CPAF) and were clearly present in 2D......-PAGE profiles of whole lysates of infected cells but absent from purified Chlamydia. CPAF was recently identified by Zhong and colleagues as a secreted protease which cleaves host cell transcription factors essential for MHC class I and II antigen presentation. The identification of CPAF in this paper verifies...

  11. Chlamydia control in Europe: literature review

    DEFF Research Database (Denmark)

    Low, N; S, Redmond; Alexander, K

    Executive summary The literature reviews in this report bring together published evidence about the prevalence and reproductive tract complications of chlamydia infection, and about the effectiveness and cost-effectiveness of chlamydia screening interventions. Population prevalence of chlamydia...... prevalence. Estimates of chlamydia positivity in surveys with low response rates should not be interpreted as estimates of population prevalence. Only two population-based surveys in EU/EEA Member States in this review had a response rate of >70%. The highest response rates were seen when specimens...

  12. Diagnostic Procedures to Detect Chlamydia trachomatis Infections.

    Science.gov (United States)

    Meyer, Thomas

    2016-08-05

    The intracellular life style of chlamydia and the ability to cause persistent infections with low-grade replication requires tests with high analytical sensitivity to directly detect C. trachomatis (CT) in medical samples. Nucleic acid amplification tests (NAATs) are the most sensitive assays with a specificity similar to cell culture and are considered the method of choice for CT detection. In addition, NAATs can be performed on various clinical specimens that do not depend on specific transport and storage conditions, since NAATs do not require infectious bacteria. In the case of lower genital tract infections, first void urine and vaginal swabs are the recommended specimens for testing males and females, respectively. Infections of anorectal, oropharyngeal and ocular epithelia should also be tested by NAAT analysis of corresponding mucosal swabs. In particular, anorectal infections of men who have sex with men (MSM) should include evaluation of lymphogranuloma venereum (LGV) by identification of genotypes L1, L2 or L3. Detection of CT antigens by enzyme immunoassay (EIAs) or rapid diagnostic tests (RDTs) are unsuitable due to insufficient sensitivity and specificity. Recent PCR-based RDTs, however, are non-inferior to standard NAATs, and might be used at the point-of-care. Serology finds application in the diagnostic work-up of suspected chronic CT infection but is inappropriate to diagnose acute infections.

  13. The influence of beryllium on cell survival rates in theIn-vitro culture system, on intracellular DNA synthesis and on SRBC-IgM antibody production responses

    OpenAIRE

    Yoshida, Tsutomu; Shima , Syogo; Kurita , Hideki; Nagaoka, Kaoru; Taniwaki, Hiroshige; Asada, Yasuki; Shai , Kai-ping; Koike, Mitsumasa; Morita, Kunihiko

    1997-01-01

    Immunocytotoxicity of beryllium (Be) was evaluated by studying cell viability, intracellular DNA synthesis and SRBC-IgM response in an in-vitro culture system using non-sensitized spleen cells of a C57BL mouse. Be addition showed a suppressive effect on cell viability, an enhancing effect on DNA synthesis and on IgM antibody production. The suppressive effect on cell viability manifested itself markedly as the concentration of Be was increased or the culture time was prolonged. The DNA synthe...

  14. Detection of Chlamydia in postmortal formalin-fixed tissue

    DEFF Research Database (Denmark)

    Lundemose, A G; Banner, Jytte; Birkelund, Svend;

    1989-01-01

    A procedure to detect Chlamydia in postmortal formalin-fixed tissue is described. Monoclonal antibodies against a genus specific chlamydia epitope were used in immunofluorescence to detect chlamydia inclusions in formalin-fixed tissue sections. Lung sections from chlamydia-infected mice were exam...

  15. The abcEDCBA-Encoded ABC Transporter and the virB Operon-Encoded Type IV Secretion System of Brucella ovis Are Critical for Intracellular Trafficking and Survival in Ovine Monocyte-Derived Macrophages.

    Directory of Open Access Journals (Sweden)

    Auricelio A Macedo

    Full Text Available Brucella ovis infection is associated with epididymitis, orchitis and infertility in rams. Most of the information available on B. ovis and host cell interaction has been generated using murine macrophages or epithelial cell lines, but the interaction between B. ovis and primary ovine macrophages has not been studied. The aim of this study was to evaluate the role of the B. ovis abcEDCBA-encoded ABC transporter and the virB operon-encoded Type IV Secretion System (T4SS during intracellular survival of B. ovis in ovine peripheral blood monocyte-derived macrophages. ΔabcBA and ΔvirB2 mutant strains were unable to survive in the intracellular environment when compared to the WT B. ovis at 48 hours post infection (hpi. In addition, these mutant strains cannot exclude the lysosomal marker LAMP1 from its vacuolar membrane, and their vacuoles do not acquire the endoplasmic reticulum marker calreticulin, which takes place in the WT B. ovis containing vacuole. Higher levels of nitric oxide production were observed in macrophages infected with WT B. ovis at 48 hpi when compared to macrophages infected with the ΔabcBA or ΔvirB2 mutant strains. Conversely, higher levels of reactive oxygen species were detected in macrophages infected with the ΔabcBA or ΔvirB2 mutant strains at 48 hpi when compared to macrophages infected with the WT strain. Our results demonstrate that B. ovis is able to persist and multiply in ovine macrophages, while ΔabcBA and ΔvirB2 mutations prevent intracellular multiplication, favor phagolysosome fusion, and impair maturation of the B. ovis vacuole towards an endoplasmic reticulum-derived compartment.

  16. Activity of Cathelicidin Peptides against Chlamydia spp.

    Science.gov (United States)

    Donati, Manuela; Di Leo, Korinne; Benincasa, Monica; Cavrini, Francesca; Accardo, Silvia; Moroni, Alessandra; Gennaro, Renato; Cevenini, Roberto

    2005-01-01

    The in vitro activity of six cathelicidin peptides against 25 strains of Chlamydia was investigated. SMAP-29 proved to be the most active peptide, reducing the inclusion numbers of all 10 strains of Chlamydia trachomatis tested by ≥50% at 10 μg/ml. This peptide was also active against C. pneumoniae and C. felis. PMID:15728927

  17. Fierce competition between Toxoplasma and Chlamydia for host cell structures in dually infected cells.

    Science.gov (United States)

    Romano, Julia D; de Beaumont, Catherine; Carrasco, Jose A; Ehrenman, Karen; Bavoil, Patrik M; Coppens, Isabelle

    2013-02-01

    The prokaryote Chlamydia trachomatis and the protozoan Toxoplasma gondii, two obligate intracellular pathogens of humans, have evolved a similar modus operandi to colonize their host cell and salvage nutrients from organelles. In order to gain fundamental knowledge on the pathogenicity of these microorganisms, we have established a cell culture model whereby single fibroblasts are coinfected by C. trachomatis and T. gondii. We previously reported that the two pathogens compete for the same nutrient pools in coinfected cells and that Toxoplasma holds a significant competitive advantage over Chlamydia. Here we have expanded our coinfection studies by examining the respective abilities of Chlamydia and Toxoplasma to co-opt the host cytoskeleton and recruit organelles. We demonstrate that the two pathogen-containing vacuoles migrate independently to the host perinuclear region and rearrange the host microtubular network around each vacuole. However, Toxoplasma outcompetes Chlamydia to the host microtubule-organizing center to the detriment of the bacterium, which then shifts to a stress-induced persistent state. Solely in cells preinfected with Chlamydia, the centrosomes become associated with the chlamydial inclusion, while the Toxoplasma parasitophorous vacuole displays growth defects. Both pathogens fragment the host Golgi apparatus and recruit Golgi elements to retrieve sphingolipids. This study demonstrates that the productive infection by both Chlamydia and Toxoplasma depends on the capability of each pathogen to successfully adhere to a finely tuned developmental program that aims to remodel the host cell for the pathogen's benefit. In particular, this investigation emphasizes the essentiality of host organelle interception by intravacuolar pathogens to facilitate access to nutrients.

  18. Advances in sampling and screening for chlamydia.

    Science.gov (United States)

    Hocking, Jane S; Guy, Rebecca; Walker, Jennifer; Tabrizi, Sepehr N

    2013-03-01

    Chlamydia is the most commonly diagnosed bacterial sexually transmitted infection in the developed world, with diagnosis rates continuing to increase each year. As chlamydia is largely asymptomatic, screening and treatment is the main way to detect cases and reduce transmission. Recent advances in self-collected specimens and laboratory tests has made chlamydia screening easier to implement as well as possible in nonclinical settings. This review will discuss new approaches to specimen collection and how these have expanded opportunities for reaching target populations for chlamydia screening. Furthermore, it will discuss how advanced molecular microbiological methods can be used with self-collected specimens to further our knowledge of the epidemiology of chlamydia and the dynamics of transmission.

  19. Chlamydia trachomatis responds to heat shock, penicillin induced persistence, and IFN-gamma persistence by altering levels of the extracytoplasmic stress response protease HtrA

    Directory of Open Access Journals (Sweden)

    Mathews Sarah A

    2008-11-01

    Full Text Available Abstract Background Chlamydia trachomatis, an obligate intracellular human pathogen, is the most prevalent bacterial sexually transmitted infection worldwide and a leading cause of preventable blindness. HtrA is a virulence and stress response periplasmic serine protease and molecular chaperone found in many bacteria. Recombinant purified C. trachomatis HtrA has been previously shown to have both activities. This investigation examined the physiological role of Chlamydia trachomatis HtrA. Results The Chlamydia trachomatis htrA gene complemented the lethal high temperature phenotype of Escherichia coli htrA- (>42°C. HtrA levels were detected to increase by western blot and immunofluorescence during Chlamydia heat shock experiments. Confocal laser scanning microscopy revealed a likely periplasmic localisation of HtrA. During penicillin induced persistence of Chlamydia trachomatis, HtrA levels (as a ratio of LPS were initially less than control acute cultures (20 h post infection but increased to more than acute cultures at 44 h post infection. This was unlike IFN-γ persistence where lower levels of HtrA were observed, suggesting Chlamydia trachomatis IFN-γ persistence does not involve a broad stress response. Conclusion The heterologous heat shock protection for Escherichia coli, and increased HtrA during cell wall disruption via penicillin and heat shock, indicates an important role for HtrA during high protein stress conditions for Chlamydia trachomatis.

  20. Phosphoproteomic analysis of the Chlamydia caviae elementary body and reticulate body forms.

    Science.gov (United States)

    Fisher, Derek J; Adams, Nancy E; Maurelli, Anthony T

    2015-08-01

    Chlamydia are Gram-negative, obligate intracellular bacteria responsible for significant diseases in humans and economically important domestic animals. These pathogens undergo a unique biphasic developmental cycle transitioning between the environmentally stable elementary body (EB) and the replicative intracellular reticulate body (RB), a conversion that appears to require extensive regulation of protein synthesis and function. However, Chlamydia possess a limited number of canonical mechanisms of transcriptional regulation. Ser/Thr/Tyr phosphorylation of proteins in bacteria has been increasingly recognized as an important mechanism of post-translational control of protein function. We utilized 2D gel electrophoresis coupled with phosphoprotein staining and MALDI-TOF/TOF analysis to map the phosphoproteome of the EB and RB forms of Chlamydia caviae. Forty-two non-redundant phosphorylated proteins were identified (some proteins were present in multiple locations within the gels). Thirty-four phosphorylated proteins were identified in EBs, including proteins found in central metabolism and protein synthesis, Chlamydia-specific hypothetical proteins and virulence-related proteins. Eleven phosphorylated proteins were identified in RBs, mostly involved in protein synthesis and folding and a single virulence-related protein. Only three phosphoproteins were found in both EB and RB phosphoproteomes. Collectively, 41 of 42 C. caviae phosphoproteins were present across Chlamydia species, consistent with the existence of a conserved chlamydial phosphoproteome. The abundance of stage-specific phosphoproteins suggests that protein phosphorylation may play a role in regulating the function of developmental-stage-specific proteins and/or may function in concert with other factors in directing EB-RB transitions.

  1. Expression of human poly (ADP-ribose) polymerase 1 in Saccharomyces cerevisiae: Effect on survival, homologous recombination and identification of genes involved in intracellular localization

    Energy Technology Data Exchange (ETDEWEB)

    La Ferla, Marco; Mercatanti, Alberto; Rocchi, Giulia; Lodovichi, Samuele; Cervelli, Tiziana; Pignata, Luca [Yeast Genetics and Genomics, Institute of Clinical Physiology, National Council of Research (CNR), via Moruzzi 1, 56122 Pisa (Italy); Caligo, Maria Adelaide [Section of Genetic Oncology, University Hospital and University of Pisa, via Roma 57, 56125 Pisa (Italy); Galli, Alvaro, E-mail: alvaro.galli@ifc.cnr.it [Yeast Genetics and Genomics, Institute of Clinical Physiology, National Council of Research (CNR), via Moruzzi 1, 56122 Pisa (Italy)

    2015-04-15

    Highlights: • The human poly (ADP-ribose) polymerase 1 (PARP-1) gene affects growth and UV-induced homologous recombination in yeast. • PARP-1 chemical inhibition impacts yeast growth and UV-induced recombination. • A genome-wide screen identifies 99 yeast genes that suppress the growth defect inferred by PARP-1. • Bioinformatics analysis identifies 41 human orthologues that may have a role in PARP-1 intracellular localization. • The findings suggest that PARP-1 nuclear localization may affect the response to PARP inhibitors in cancer therapy. - Abstract: The poly (ADP-ribose) polymerase 1 (PARP-1) actively participates in a series of functions within the cell that include: mitosis, intracellular signaling, cell cycle regulation, transcription and DNA damage repair. Therefore, inhibition of PARP1 has a great potential for use in cancer therapy. As resistance to PARP inhibitors is starting to be observed in patients, thus the function of PARP-1 needs to be studied in depth in order to find new therapeutic targets. To gain more information on the PARP-1 activity, we expressed PARP-1 in yeast and investigated its effect on cell growth and UV induced homologous recombination. To identify candidate genes affecting PARP-1 activity and cellular localization, we also developed a yeast genome wide genetic screen. We found that PARP-1 strongly inhibited yeast growth, but when yeast was exposed to the PARP-1 inhibitor 6(5-H) phenantridinone (PHE), it recovered from the growth suppression. Moreover, we showed that PARP-1 produced PAR products in yeast and we demonstrated that PARP-1 reduced UV-induced homologous recombination. By genome wide screening, we identified 99 mutants that suppressed PARP-1 growth inhibition. Orthologues of human genes were found for 41 of these yeast genes. We determined whether the PARP-1 protein level was altered in strains which are deleted for the transcription regulator GAL3, the histone H1 gene HHO1, the HUL4 gene, the

  2. Role of Leishmania (Leishmania chagasi amastigote cysteine protease in intracellular parasite survival: studies by gene disruption and antisense mRNA inhibition

    Directory of Open Access Journals (Sweden)

    Kucknoor Ashwini S

    2005-02-01

    Full Text Available Abstract Background The parasitic protozoa belonging to Leishmania (L. donovani complex possess abundant, developmentally regulated cathepsin L-like cysteine proteases. Previously, we have reported the isolation of cysteine protease gene, Ldccys2 from Leishmania (L. chagasi. Here, we have further characterized this cysteine protease gene and demonstrated its role during infection and survival of Leishmania (L. chagasi within the U937 macrophage cells. Results The amastigote specific Ldccys2 genes of L. (L. chagasi and L. (L. donovani have identical gene organization, as determined by southern blots. In vivo expression analyses by Northern blots showed that Ldccys2 is amastigote specific. Western blot using anti-Ldccys2 antibody confirmed the amastigote specific protein expression. Recombinant expression of Ldccys2, a 30 kDA protein, was functionally active in a gelatin assay. Results from Ldccys2 heterozygous knockout mutants showed its role during macrophage infection and in intra-macrophage survival of the parasites. Since attempts to generate null mutants failed, we used antisense RNA inhibition to regulate Ldcccys2 gene expression. Not surprisingly, the results from antisense studies further confirmed the results from heterozygous knockout mutants, reiterating the importance of amastigote specific cysteine proteases in Leishmania infection and pathogenesis. Conclusions The study shows that Ldccys2 is a developmentally regulated gene and that Ldccys2 is expressed only in infectious amastigote stages of the parasite. The collective results from both the heterozygous knockout mutants and antisense mRNA inhibition studies shows that Ldccys2 helps in infection and survival of L. (L. chagasi amastigotes within the macrophage cells. Finally, antisense RNA technique can be used as an alternate approach to gene knockout, for silencing gene expression in L. (L. chagasi, especially in cases such as this, where a null mutant cannot be achieved by

  3. Seroprevalence and risk factors of Chlamydia infection in dogs in Southwestern China.

    Science.gov (United States)

    Tian, Yi-Ming; Cao, Jing-Feng; Zhou, Dong-Hui; Zou, Feng-Cai; Miao, Qiang; Liu, Zi-Li; Li, Bi-Feng; Lv, Rui-Qing; Du, Xiao-Peng; Zhu, Xing-Quan

    2014-02-01

    Chlamydia spp. are obligate intracellular bacteria distributed globally, known to cause various forms of diseases in animals and humans. To date, there is limited information about the seroprevalence of Chlamydia and the risk factors associated with Chlamydia infection in dogs in the world. In the present study, a serological survey was undertaken to examine the seroprevalence and risk factors associated with dog chlamydiosis in Yunnan Province, southwestern China. A total of 591 dogs were sampled, antibodies to Chlamydia were determined by indirect hemagglutination assay (IHA). The overall seroprevalence was estimated at 17.6%. The risk factors associated with seroprevalence were determined by a multivariate logistic regression analysis. Gender and age of dogs were not significant in the logistic regression analysis (P>0.05) and left out of the final model. Type and geographical origin of dogs were considered as main risk factors associated with Chlamydia infection, stray dogs (31.37%) were more than 16 times (OR=16.167, 95% CI=6.283-41.599, Pcompared to the police dogs (7.62%), while pet dogs (14.41%) had a 3 times (OR=2.968, 95% CI=1.349-6.529, P=0.007) higher risk. Positive dogs were found in 5 districts of Yunnan Province with prevalence ranging from 2.56% to 31.67% except Diqing (0/56). Dogs in Kunming (20.21%) had a 9 times higher risk of being seropositive compared to dogs in Lijiang (2.56%) (OR=9.057, 95% CI=1.211-67.714, P=0.032), although no regional differences were found in other 4 administrative divisions compared to Lijiang (P>0.05). Our study revealed a widespread and high prevalence of Chlamydia infection in dogs in Yunnan Province, southwestern China, with higher exposure risk in stray dogs and distinct geographical distribution. These findings suggest the potential importance of dogs in the transmission of zoonotic Chlamydia infection, and thus Chlamydia should be taken into consideration in diagnosing dog diseases.

  4. Functional characterization delineates that a Mycobacterium tuberculosis specific protein kinase (Rv3080c) is responsible for the growth, phagocytosis and intracellular survival of avirulent mycobacteria.

    Science.gov (United States)

    Kumari, Ruma; Singh, Susmita K; Singh, Diwakar K; Singh, Pramod K; Chaurasiya, Shivendra K; Srivastava, Kishore K

    2012-10-01

    Serine/threonine protein kinases (STPKs) are predominantly involved in growth, development, division, differentiation, and in regulating immune responses in mycobacteria. A wide variety of functions of mycobacterial STPKs persuade mycobacterial growth and further its survival in the hosts. The polymorphic studies have shown that a full length gene of Rv3080c (pknK) is present in the slow growing mycobacteria. The wild type Mycobacterium smegmatis containing only vector (M. smegmatis) and M. smegmatis containing Rv3080c (pknK) cloned in pMV261 vector (M. smegmatis::K) were cultured in different growth media. The studies have shown that M. smegmatis did not differ in the growth and in survival while a substantial reduction in the growth (four-ten-folds) and a significant delay in the colony formation were observed in M. smegmatis::K. In order to look for the stage specific and modulated expression of PknK, the study was comprehended to quantitate pknK transcripts at different phases of cultures. The mycobacterium, containing high copy number of pknK specific RNA was unable to multiply. The study thus highlights that Rv3080c is largely accountable for changing the fate of avirulent mycobacteria and hence the protein can be utilized as an important molecule to target pathogenesis.

  5. Analysis of glycosidases activity in Chlamydia trachomatis L2 serotype

    Directory of Open Access Journals (Sweden)

    Dr. Sanjiv Rughooputh

    2006-01-01

    Full Text Available Chlamydiae are prokaryotic, gram negative, intracellular parasites, causing a number of human diseases with serious sequelae. The exact mechanism of chlamydial attachment and entry into the host cell is still unclear. Chlamydia trachomatis, SA2F (L2 was tested for the activity of glycosidases. Glycosidases are involved in the synthesis and breakdown of cell-wall polysaccharides, and have a pivotal role in attachment to the surface of host cells as well as in the invasion process of other infective agents. For these reasons, glycosidases are likely to provide important information regarding the general behaviour of this bacterium. Ten different glycosides bound to p-nitrophenol (pNP substrate were tested. Assays were performed on lysed and unlysed chlamydial extracts.Our results provided strong evidence for the existence of glycosidase activity in C.trachomatis, strain SA2F peaking at pH 5.0 and pH 7.5-8.0 There was a high enzymatic activity against p-NPa mannopyranoside and p-NP b-N acetylglucosamine with a recovery of 88% suggesting that the enzymes were present on the bacterial surface. Activity against these sugars, which form part of either the extracellular filler or in endoplasmic reticulum may suggest of a possible mechanism of cellular invasion.

  6. Comparison between ICT and PCR for diagnosis of Chlamydia trachomatis.

    Science.gov (United States)

    Khan, E R; Hossain, M A; Paul, S K; Mahmud, C; Hasan, M M; Rahman, M M; Nahar, K; Kubayashi, N

    2012-04-01

    Chlamydia trachomatis is an obligate intracellular gram-negative bacterium which is the most prevalent cause of bacterial sexually transmitted infections (STI). The present study was carried to diagnose genital Chlamydia trachomatis infection among women of reproductive age, attending Mymensingh Medical College Hospital, during July 2009 to June 2010 by Immunochromatographic test (ICT) and Polymerase chain reaction (PCR). A total of 70 females were included in this study. Out of 70 cases 56 were symptomatic and 14 asymptomatic. Endocervical swabs were collected from each of the cases and examined by Immunochromatographic test (ICT) for antigen detection and Polymerase chain reaction (PCR) for detection of endogenous plasmid-based nucleic acid. A total 29(41.4%) of the cases were found positive for C. trachomatis either by ICT or PCR. Of the 56 symptomatic cases, 19(33.9%) were found ICT positive and 17(30.4%) were PCR positive. Among 14 asymptomatic females, 2(14.3%) were ICT positive and none were PCR positive. Though PCR is highly sensitive but a total of twelve cases were found ICT positive but PCR negative. It may be due to presence of plasmid deficient strain of C trachomatis which could be amplified by ompA based (Chromosomal gene) multiplex PCR.

  7. Characterization of the intracellular survival of Mycobacterium avium ssp. paratuberculosis: phagosomal pH and fusogenicity in J774 macrophages compared with other mycobacteria.

    Science.gov (United States)

    Kuehnel, M P; Goethe, R; Habermann, A; Mueller, E; Rohde, M; Griffiths, G; Valentin-Weigand, P

    2001-08-01

    The phagosomes containing viable pathogenic mycobacteria, such as Mycobacterium (M.) tuberculosis and Mycobacterium avium ssp. avium (M. avium), are known to be limited in their ability to both acidify and fuse with late (but not early) endocytic organelles. Here, we analysed the pH and fusogenicity of phagosomes containing M. avium ssp. paratuberculosis (M. ptb), the causative agent of paratuberculosis in ruminants. Using the murine J774 macrophage cell line, we compared viable and heat-killed M. ptb and, in addition, viable or dead M. avium, as well as two non-pathogenic mycobacteria, Mycobacterium smegmatis and Mycobacterium gordonae. Electron microscopic analysis revealed that M. ptb persisted intracellularly in phagosomes for up to 15 days. The phagosomes containing live M. ptb and M. avium were significantly reduced in their ability to acquire some markers for the endocytic pathway, such as internalized calcein, BSA-gold or the membrane protein Lamp 2. However, they were almost completely accessible to 70 kDa fluorescein isothiocyanate (FITC)-dextran and Lamp 1. Overall, the phagosomes containing dead pathogenic mycobacteria behaved similarly to the ones containing live non-pathogenic mycobacteria in all experiments. Using FITC-dextran in a novel fluorescence-activated cell sorting (FACS)-based method, we could also show that the bulk of endocytic compartments, including phagosomes, were only very mildly acidified to approximately pH 6.3 over at least 72 h in J774 cells infected with live M. ptb and M. avium. In contrast, J774 cells treated with heat-killed M. ptb or BSA-coated latex beads showed substantial acidification of the phagosome/endocytic compartments to a pH value of approximately 5.2. After infection with M. smegmatis and M. gordonae, acidification was initially (1-5 h after infection) inhibited, but increased after longer infection to levels similar to those with dead mycobacteria.

  8. Pneumonia grave por "Chlamydia psittaci"

    Directory of Open Access Journals (Sweden)

    MOSCHIONI CRISTIANE

    2001-01-01

    Full Text Available A psitacose, também conhecida como ornitose, é causada pela Chlamydia psittaci; caracteriza-se por doença de início insidioso, sintomas brandos e inespecíficos, lembrando infecção de vias aéreas superiores. Acomete principalmente o pulmão, sendo raramente doença sistêmica e fatal. Descreve-se um caso raro de pneumonia por Chlamydia psittaci que evoluiu para insuficiência respiratória aguda, necessitando de ventilação mecânica. Destaca-se a importância em considerar o diagnóstico, especialmente em casos de pneumonia comunitária que evolui de modo insatisfatório, que não responde à terapia antimicrobiana e cuja epidemiologia é positiva para exposição às aves. O diagnóstico precoce é fundamental devido à excelente resposta terapêutica. O diagnóstico tardio pode levar a curso grave e fatal da doença.

  9. Expression of human poly (ADP-ribose) polymerase 1 in Saccharomyces cerevisiae: Effect on survival, homologous recombination and identification of genes involved in intracellular localization.

    Science.gov (United States)

    La Ferla, Marco; Mercatanti, Alberto; Rocchi, Giulia; Lodovichi, Samuele; Cervelli, Tiziana; Pignata, Luca; Caligo, Maria Adelaide; Galli, Alvaro

    2015-04-01

    The poly (ADP-ribose) polymerase 1 (PARP-1) actively participates in a series of functions within the cell that include: mitosis, intracellular signaling, cell cycle regulation, transcription and DNA damage repair. Therefore, inhibition of PARP1 has a great potential for use in cancer therapy. As resistance to PARP inhibitors is starting to be observed in patients, thus the function of PARP-1 needs to be studied in depth in order to find new therapeutic targets. To gain more information on the PARP-1 activity, we expressed PARP-1 in yeast and investigated its effect on cell growth and UV induced homologous recombination. To identify candidate genes affecting PARP-1 activity and cellular localization, we also developed a yeast genome wide genetic screen. We found that PARP-1 strongly inhibited yeast growth, but when yeast was exposed to the PARP-1 inhibitor 6(5-H) phenantridinone (PHE), it recovered from the growth suppression. Moreover, we showed that PARP-1 produced PAR products in yeast and we demonstrated that PARP-1 reduced UV-induced homologous recombination. By genome wide screening, we identified 99 mutants that suppressed PARP-1 growth inhibition. Orthologues of human genes were found for 41 of these yeast genes. We determined whether the PARP-1 protein level was altered in strains which are deleted for the transcription regulator GAL3, the histone H1 gene HHO1, the HUL4 gene, the deubiquitination enzyme gene OTU1, the nuclear pore protein POM152 and the SNT1 that encodes for the Set3C subunit of the histone deacetylase complex. In these strains the PARP-1 level was roughly the same as in the wild type. PARP-1 localized in the nucleus more in the snt1Δ than in the wild type strain; after UV radiation, PARP-1 localized in the nucleus more in hho1 and pom152 deletion strains than in the wild type indicating that these functions may have a role on regulating PARP-1 level and activity in the nucleus.

  10. Immunoelectron microscopy of lipopolysaccharide in Chlamydia trachomatis

    DEFF Research Database (Denmark)

    Birkelund, Svend; Lundemose, AG; Christiansen, Gunna

    1989-01-01

    Monoclonal antibodies (MAb) specific for Chlamydia trachomatis lipopolysaccharide (LPS) and major outer membrane protein (MOMP) were used for immunoelectron microscopy analysis. MAb specific for MOMP showed strong reaction with the chlamydial surface, whereas MAb specific for LPS showed strong...

  11. NNDSS - Table II. Chlamydia to Coccidioidomycosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Chlamydia to Coccidioidomycosis - 2016. In this Table, provisional* cases of selected†notifiable diseases (≥1,000 cases reported during the...

  12. NNDSS - Table II. Chlamydia to Coccidioidomycosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Chlamydia to Coccidioidomycosis - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the...

  13. NNDSS - Table II. Chlamydia to Coccidioidomycosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Chlamydia to Coccidioidomycosis - 2015.In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the...

  14. Corynebacterium diphtheriae putative tellurite-resistance protein (CDCE8392_0813 contributes to the intracellular survival in human epithelial cells and lethality of Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Louisy Sanches dos Santos

    2015-01-01

    Full Text Available Corynebacterium diphtheriae, the aetiologic agent of diphtheria, also represents a global medical challenge because of the existence of invasive strains as causative agents of systemic infections. Although tellurite (TeO32- is toxic to most microorganisms, TeO32--resistant bacteria, including C. diphtheriae, exist in nature. The presence of TeO32--resistance (TeR determinants in pathogenic bacteria might provide selective advantages in the natural environment. In the present study, we investigated the role of the putative TeR determinant (CDCE8392_813 gene in the virulence attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen species (hydrogen peroxide, but not to other antimicrobial agents. The LDCIC-L1 mutant also showed a decrease in both the lethality of Caenorhabditis elegans and the survival inside of human epithelial cells compared to wild-type strain. Conversely, the haemagglutinating activity and adherence to and formation of biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813 gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and pathogenic potential of C. diphtheriae.

  15. Corynebacterium diphtheriae putative tellurite-resistance protein (CDCE8392_0813) contributes to the intracellular survival in human epithelial cells and lethality of Caenorhabditis elegans.

    Science.gov (United States)

    Santos, Louisy Sanches Dos; Antunes, Camila Azevedo; Santos, Cintia Silva Dos; Pereira, José Augusto Adler; Sabbadini, Priscila Soares; Luna, Maria das Graças de; Azevedo, Vasco; Hirata Júnior, Raphael; Burkovski, Andreas; Asad, Lídia Maria Buarque de Oliveira; Mattos-Guaraldi, Ana Luíza

    2015-08-01

    Corynebacterium diphtheriae, the aetiologic agent of diphtheria, also represents a global medical challenge because of the existence of invasive strains as causative agents of systemic infections. Although tellurite (TeO32-) is toxic to most microorganisms, TeO32--resistant bacteria, including C. diphtheriae, exist in nature. The presence of TeO32--resistance (TeR) determinants in pathogenic bacteria might provide selective advantages in the natural environment. In the present study, we investigated the role of the putative TeR determinant (CDCE8392_813gene) in the virulence attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen species (hydrogen peroxide), but not to other antimicrobial agents. The LDCIC-L1 mutant also showed a decrease in both the lethality of Caenorhabditis elegans and the survival inside of human epithelial cells compared to wild-type strain. Conversely, the haemagglutinating activity and adherence to and formation of biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813 gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and pathogenic potential of C. diphtheriae.

  16. Corynebacterium diphtheriae putative tellurite-resistance protein (CDCE8392_0813 contributes to the intracellular survival in human epithelial cells and lethality of Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Louisy Sanches dos Santos

    2015-08-01

    Full Text Available Corynebacterium diphtheriae, the aetiologic agent of diphtheria, also represents a global medical challenge because of the existence of invasive strains as causative agents of systemic infections. Although tellurite (TeO32- is toxic to most microorganisms, TeO32--resistant bacteria, including C. diphtheriae, exist in nature. The presence of TeO32--resistance (TeR determinants in pathogenic bacteria might provide selective advantages in the natural environment. In the present study, we investigated the role of the putative TeR determinant (CDCE8392_813gene in the virulence attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen species (hydrogen peroxide, but not to other antimicrobial agents. The LDCIC-L1 mutant also showed a decrease in both the lethality of Caenorhabditis elegansand the survival inside of human epithelial cells compared to wild-type strain. Conversely, the haemagglutinating activity and adherence to and formation of biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813 gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and pathogenic potential of C. diphtheriae.

  17. [Chlamydia trachomatis infection in the cervix uteri].

    Science.gov (United States)

    Rosas Arceo, J; Toca Porraz, L; Díaz Esponda, C; Nava Flores, J

    1993-11-01

    We studied 93 gynecological samples of uterine cervix of patients at Hospital de Gineco Obstetricia No. 3, Centro Médico La Raza, IMSS, Health Promotion and Family Medicine Unit No. 5 with monoclonal antibodies. We found Chlamydia trachomatis in 28.4% in women where the infection was suspected. We should think in infection by Chlamydia trachomatis in women with acute cervicitis, acute salpingitis, cervical abnormalities, and to run the specific tests for its detection.

  18. An inducible and secreted eukaryote-like serine/threonine kinase of Salmonella enterica serovar Typhi promotes intracellular survival and pathogenesis.

    Science.gov (United States)

    Theeya, Nagaraja; Ta, Atri; Das, Sayan; Mandal, Rahul S; Chakrabarti, Oishee; Chakrabarti, Saikat; Ghosh, Amar N; Das, Santasabuj

    2015-02-01

    Eukaryote-like serine/threonine kinases (eSTKs) constitute an important family of bacterial virulence factors. Genome analysis had predicted putative eSTKs in Salmonella enterica serovar Typhi, although their functional characterization and the elucidation of their role in pathogenesis are still awaited. We show here that the primary sequence and secondary structure of the t4519 locus of Salmonella Typhi Ty2 have all the signatures of eukaryotic superfamily kinases. t4519 encodes a ∼39-kDa protein (T4519), which shows serine/threonine kinase activities in vitro. Recombinant T4519 (rT4519) is autophosphorylated and phosphorylates the universal substrate myelin basic protein. Infection of macrophages results in decreased viability of the mutant (Ty2Δt4519) strain, which is reversed by gene complementation. Moreover, reactive oxygen species produced by the macrophages signal to the bacteria to induce T4519, which is translocated to the host cell cytoplasm. That T4519 may target a host substrate(s) is further supported by the activation of host cellular signaling pathways and the induction of cytokines/chemokines. Finally, the role of T4519 in the pathogenesis of Salmonella Typhi is underscored by the significantly decreased mortality of mice infected with the Ty2Δt4519 strain and the fact that the competitive index of this strain for causing systemic infection is 0.25% that of the wild-type strain. This study characterizes the first eSTK of Salmonella Typhi and demonstrates its role in promoting phagosomal survival of the bacteria within macrophages, which is a key determinant of pathogenesis. This, to the best of our knowledge, is the first study to describe the essential role of eSTKs in the in vivo pathogenesis of Salmonella spp.

  19. Prevalence of Chlamydia psittaci and Other Chlamydia Species in Wild Birds in Poland.

    Science.gov (United States)

    Krawiec, Marta; Piasecki, Tomasz; Wieliczko, Alina

    2015-11-01

    Avian chlamydiosis is a zoonotic disease occurring in humans, poultry, and exotic birds. It has been suggested that some wild bird species play an important role as reservoirs for Chlamydia, especially Chlamydia psittaci. Whereas C. psittaci is the predominant chlamydial agent in birds, in the present study we have determined the prevalence of different species of Chlamydia among selected wild bird species in Poland using a rapid and sensitive real-time PCR method. In total, 369 free-living birds from 35 bird species and 15 orders were examined. Samples from 27 birds (7.3%) were positive for chlamydial DNA in the PCR; 22 positive samples (81.5%) belonged to C. psittaci, three to Chlamydia trachomatis (11.1%), and two (7.4%) classified only to the genus Chlamydia. Most of C. psittaci-positive samples belonged to five orders: Anseriformes, Columbiformes, Gruiformes, Phasianiformes, and Passeriformes. All C. trachomatis samples were obtained from Eurasian coots (Gruiformes). Two Chlamydia-positive samples not classified to any Chlamydia species were obtained from a common wood pigeon (Columbiformes) and a common buzzard (Accipitriformes). Detection of C. psittaci and C. trachomatis in free-living bird populations force to think on significance of birds as reservoir of varied Chlamydia species and their epidemiological importance.

  20. Coinfection of Chlamydiae and other Bacteria in Reactive Arthritis and Spondyloarthritis: Need for Future Research

    Directory of Open Access Journals (Sweden)

    Henning Zeidler

    2016-08-01

    Full Text Available Reactive (inflammatory arthritis has been known for many years to follow genital infection with the intracellular bacterial pathogen Chlamydia trachomatis in some individuals. Recent studies from several groups have demonstrated that a related bacterium, the respiratory pathogen Chlamydia pneumoniae, can elicit a similar arthritis. Studies of these organisms, and of a set of gastrointestinal pathogens also associated with engendering inflammatory arthritis, have been relatively extensive. However, reports focusing on coinfections with these and/or other organisms, and the effects of such coinfections on the host immune and other systems, have been rare. In this article, we review the extant data regarding infections by multiple pathogens in the joint as they relate to engendering arthritis, and we suggest a number of research areas that must be given a high priority if we are to understand, and therefore to treat in an effective manner, such arthritides.

  1. Chlamydia trachomatis sigma28 recognizes the fliC promoter of Escherichia coli and responds to heat shock in chlamydiae.

    Science.gov (United States)

    Shen, Li; Li, Maixiang; Zhang, You-Xun

    2004-01-01

    The rpsD gene of Chlamydia trachomatis encodes the alternative sigma factor sigma28, which bears strong homology to many bacterial sigma factors, including Escherichia coli sigma8 and Bacillus subtilis sigmaB and sigmaD. Recently, a sigma28 promoter was identified upstream of the late-cycle-expressed gene hctB, which encodes the Chlamydia-histone-like protein 2 (Yu & Tan, 2003). In this study it is shown that the product of chlamydial rpsD is an E. coli sigma28 homologue. It was found that recombinant chlamydial sigma8, in combination with E. coli core RNA polymerase, initiates transcription in vitro from the E. coli sigma28-dependent promoter of fliC. It was also demonstrated that the recombinant chlamydial sigma28 does not recognize major sigma factor sigma70-consensus-like sequences in vitro. In C. trachomatis-infected cells, two rpsD transcripts were detected with 5' ends located 18 (transcript I) and 54 bp (transcript II) upstream of the translational initiation codon at 16 and 30 h post-infection. When the temperature of cultures infected with C. trachomatis was shifted from 35 to 42 degrees C, the rpsD transcript I increased dramatically. The levels of chlamydial sigma28, relative to EF-Tu, were greater throughout the exponential growth phase of the reticulate body, but lower late in the developmental cycle. These data support the hypothesis that sigma28 plays a role in the regulatory network that allows chlamydiae to survive changes in its environment, enabling it to complete its unique developmental cycle.

  2. Evidence for the existence of two new members of the family Chlamydiaceae and proposal of Chlamydia avium sp. nov. and Chlamydia gallinacea sp. nov.

    Science.gov (United States)

    Sachse, Konrad; Laroucau, Karine; Riege, Konstantin; Wehner, Stefanie; Dilcher, Meik; Creasy, Heather Huot; Weidmann, Manfred; Myers, Garry; Vorimore, Fabien; Vicari, Nadia; Magnino, Simone; Liebler-Tenorio, Elisabeth; Ruettger, Anke; Bavoil, Patrik M; Hufert, Frank T; Rosselló-Móra, Ramon; Marz, Manja

    2014-03-01

    The family Chlamydiaceae with the recombined single genus Chlamydia currently comprises nine species, all of which are obligate intracellular organisms distinguished by a unique biphasic developmental cycle. Anecdotal evidence from epidemiological surveys in flocks of poultry, pigeons and psittacine birds have indicated the presence of non-classified chlamydial strains, some of which may act as pathogens. In the present study, phylogenetic analysis of ribosomal RNA and ompA genes, as well as multi-locus sequence analysis of 11 field isolates were conducted. All independent analyses assigned the strains into two different clades of monophyletic origin corresponding to pigeon and psittacine strains or poultry isolates, respectively. Comparative genome analysis involving the type strains of currently accepted Chlamydiaceae species and the designated type strains representing the two new clades confirmed that the latter could be classified into two different species as their average nucleotide identity (ANI) values were always below 94%, both with the closest relative species and between themselves. In view of the evidence obtained from the analyses, we propose the addition of two new species to the current classification: Chlamydia avium sp. nov. comprising strains from pigeons and psittacine birds (type strain 10DC88(T); DSMZ: DSM27005(T), CSUR: P3508(T)) and Chlamydia gallinacea sp. nov. comprising strains from poultry (type strain 08-1274/3(T); DSMZ: DSM27451(T), CSUR: P3509(T)).

  3. Importance of amoebae as a tool to isolate amoeba-resisting microorganisms and for their ecology and evolution: the Chlamydia paradigm.

    Science.gov (United States)

    Kebbi-Beghdadi, Carole; Greub, Gilbert

    2014-08-01

    Free-living amoebae are distributed worldwide and are frequently in contact with humans and animals. As cysts, they can survive in very harsh conditions and resist biocides and most disinfection procedures. Several microorganisms, called amoeba-resisting microorganisms (ARMs), have evolved to survive and multiply within these protozoa. Among them are many important pathogens, such as Legionella and Mycobacteria, and also several newly discovered Chlamydia-related bacteria, such as Parachlamydia acanthamoebae, Estrella lausannensis, Simkania negevensis or Waddlia chondrophila whose pathogenic role towards human or animal is strongly suspected. Amoebae represent an evolutionary crib for their resistant microorganisms since they can exchange genetic material with other ARMs and develop virulence traits that will be further used to infect other professional phagocytes. Moreover, amoebae constitute an ideal tool to isolate strict intracellular microorganisms from complex microbiota, since they will feed on other fast-growing bacteria, such as coliforms potentially present in the investigated samples. The paradigm that ARMs are likely resistant to macrophages, another phagocytic cell, and that they are likely virulent towards humans and animals is only partially true. Indeed, we provide examples of the Chlamydiales order that challenge this assumption and suggest that the ability to multiply in protozoa does not strictly correlate with pathogenicity and that we should rather use the ability to replicate in multiple and diverse eukaryotic cells as an indirect marker of virulence towards mammals. Thus, cell-culture-based microbial culturomics should be used in the future to try to discover new pathogenic bacterial species.

  4. Chlamydia

    Science.gov (United States)

    ... or babies born before 37 weeks of pregnancy. Premature birth is the most common cause of infant death and can lead to long-term health and ... or babies born before 37 weeks of pregnancy. Premature birth is the most common cause of infant death and can lead to long-term health and ...

  5. Inhibition of Fusion of Chlamydia trachomatis Inclusions at 32°C Correlates with Restricted Export of IncA

    OpenAIRE

    Fields, K. A.; Fischer, E.; Hackstadt, T

    2002-01-01

    Chlamydia trachomatis is an obligate intracellular bacterium that develops within a parasitophorous vacuole termed an inclusion. The inclusion is nonfusogenic with lysosomes but intercepts lipids from a host cell exocytic pathway. Initiation of chlamydial development is concurrent with modification of the inclusion membrane by a set of C. trachomatis-encoded proteins collectively designated Incs. One of these Incs, IncA, is functionally associated with the homotypic fusion of inclusions. Incl...

  6. Detection of Chlamydia in postmortal formalin-fixed tissue

    DEFF Research Database (Denmark)

    Lundemose, AG; Lundemose, JB; Birkelund, Svend;

    1989-01-01

    A procedure to detect Chlamydia in postmortal formalin-fixed tissue is described. Monoclonal antibodies against a genus specific chlamydia epitope were used in immunofluorescence to detect chlamydia inclusions in formalin-fixed tissue sections. Lung sections from chlamydia-infected mice were....... Background and non-specific fluorescence were reduced by treating the tissue sections with trypsin, rabbit serum and Evans blue counterstain. Besides giving an exact diagnosis at autopsy, the method provides the possibility of determining the occurrence of chlamydia infections in various tissues, based...

  7. Chlamydia Peritonitis and Ascites Mimicking Ovarian Cancer

    Science.gov (United States)

    Macer, Matthew; Azodi, Masoud

    2016-01-01

    Background. Pelvic inflammatory disease (PID) rarely results in diffuse ascites. Severe adhesive disease secondary to PID may lead to the formation of inclusion cysts and even pelvic peritoneal nodularity due to postinflammatory scarring and cause an elevation of serum CA-125 levels. The constellation of these findings may mimic an ovarian neoplasm. Case. We report a case of a 22-year-old female who presented with multiple pelvic cysts and diffuse ascites due to Chlamydia trachomatis infection. The initial gynecologic exam did not reveal obvious evidence of PID; however, a positive Chlamydia trachomatis test, pathologic findings, and the exclusion of other etiologies facilitated the diagnosis. Conclusion. Chlamydia trachomatis and other infectious agents should be considered in the differential diagnosis of a young sexually active female with abdominal pain, ascites, and pelvic cystic masses. Thorough workup in such a population may reduce the number of more invasive procedures as well as unnecessary repeat surgical procedures. PMID:27747116

  8. Progress in genotyping of Chlamydia trachomatis

    Institute of Scientific and Technical Information of China (English)

    Xia Yong; Xiong Likuan

    2014-01-01

    Objective To review the common genotyping techniques of Chlamydia trachomatis in terms of their principles,characteristics,applications and limitations.Data sources Data used in this review were mainly from English literatures of PubMed database.The search terms were "Chlamydia trachomatis" and "genotyping".Meanwhile,data from World Health Organization were also cited.Study selection Original articles and reviews relevant to present review's theme were selected.Results Different genotyping techniques were applied on different occasions according to their characteristics,especially in epidemiological studies worldwide,which pushed the study of Chlamydia trachomatis forward greatly.In addition,summaries of some epidemiological studies by genotyping were also included in this work for reference and comparison.Conclusions A clear understanding of common genotyping techniques could be helpful to genotype C.trachomatis more appropriately and effectively.Furthermore,more studies on the association of genotypes of Ch/amydia trachomatis with clinical manifestations should be performed.

  9. Analysis of Synonymous Codon Usage Bias in Chlamydia

    Institute of Scientific and Technical Information of China (English)

    Hui L(ü); Wei-Ming ZHAO; Yan ZHENG; Hong WANG; Mei QI; Xiu-Ping YU

    2005-01-01

    Chlamydiae are obligate intracellular bacterial pathogens that cause ocular and sexually transmitted diseases, and are associated with cardiovascular diseases. The analysis of codon usage may improve our understanding of the evolution and pathogenesis of Chlamydia and allow reengineering of target genes to improve their expression for gene therapy. Here, we analyzed the codon usage of C. muridarum, C.trachomatis (here indicating biovar trachoma and LGV), C. pneumoniae, and C. psittaci using the codon usage database and the CUSP (Create a codon usage table) program of EMBOSS (The European Molecular Biology Open Software Suite). The results show that the four genomes have similar codon usage patterns,with a strong bias towards the codons with A and T at the third codon position. Compared with Homo sapiens, the four chlamydial species show discordant seven or eight preferred codons. The ENC (effective number of codons used in a gene)-plot reveals that the genetic heterogeneity in Chlamydia is constrained by the G+C content, while translational selection and gene length exert relatively weaker influences. Moreover,mutational pressure appears to be the major determinant of the codon usage variation among the chlamydial genes. In addition, we compared the codon preferences of C. trachomatis with those of E. coli, yeast,adenovirus and Homo sapiens. There are 23 codons showing distinct usage differences between C. trachomatis and E. coli, 24 between C. trachomatis and adenovirus, 21 between C. trachomatis and Homo sapiens, but only six codons between C. trachomatis and yeast. Therefore, the yeast system may be more suitable for the expression of chlamydial genes. Finally, we compared the codon preferences of C. trachomatis with those of six eukaryotes, eight prokaryotes and 23 viruses. There is a strong positive correlation between the differences in coding GC content and the variations in codon bias (r=0.905, P<0.001). We conclude that the variation of codon bias

  10. RNAi screen in Drosophila cells reveals the involvement of the Tom complex in Chlamydia infection.

    Directory of Open Access Journals (Sweden)

    Isabelle Derré

    2007-10-01

    Full Text Available Chlamydia spp. are intracellular obligate bacterial pathogens that infect a wide range of host cells. Here, we show that C. caviae enters, replicates, and performs a complete developmental cycle in Drosophila SL2 cells. Using this model system, we have performed a genome-wide RNA interference screen and identified 54 factors that, when depleted, inhibit C. caviae infection. By testing the effect of each candidate's knock down on L. monocytogenes infection, we have identified 31 candidates presumably specific of C. caviae infection. We found factors expected to have an effect on Chlamydia infection, such as heparansulfate glycosaminoglycans and actin and microtubule remodeling factors. We also identified factors that were not previously described as involved in Chlamydia infection. For instance, we identified members of the Tim-Tom complex, a multiprotein complex involved in the recognition and import of nuclear-encoded proteins to the mitochondria, as required for C. caviae infection of Drosophila cells. Finally, we confirmed that depletion of either Tom40 or Tom22 also reduced C. caviae infection in mammalian cells. However, C. trachomatis infection was not affected, suggesting that the mechanism involved is C. caviae specific.

  11. Chlamydia infection depends on a functional MDM2-p53 axis.

    Science.gov (United States)

    González, Erik; Rother, Marion; Kerr, Markus C; Al-Zeer, Munir A; Abu-Lubad, Mohammad; Kessler, Mirjana; Brinkmann, Volker; Loewer, Alexander; Meyer, Thomas F

    2014-11-13

    Chlamydia, a major human bacterial pathogen, assumes effective strategies to protect infected cells against death-inducing stimuli, thereby ensuring completion of its developmental cycle. Paired with its capacity to cause extensive host DNA damage, this poses a potential risk of malignant transformation, consistent with circumstantial epidemiological evidence. Here we reveal a dramatic depletion of p53, a tumor suppressor deregulated in many cancers, during Chlamydia infection. Using biochemical approaches and live imaging of individual cells, we demonstrate that p53 diminution requires phosphorylation of Murine Double Minute 2 (MDM2; a ubiquitin ligase) and subsequent interaction of phospho-MDM2 with p53 before induced proteasomal degradation. Strikingly, inhibition of the p53-MDM2 interaction is sufficient to disrupt intracellular development of Chlamydia and interferes with the pathogen's anti-apoptotic effect on host cells. This highlights the dependency of the pathogen on a functional MDM2-p53 axis and lends support to a potentially pro-carcinogenic effect of chlamydial infection.

  12. In contrast to Chlamydia trachomatis, Waddlia chondrophila grows in human cells without inhibiting apoptosis, fragmenting the Golgi apparatus, or diverting post-Golgi sphingomyelin transport.

    Science.gov (United States)

    Dille, Stephanie; Kleinschnitz, Eva-Maria; Kontchou, Collins Waguia; Nölke, Thilo; Häcker, Georg

    2015-08-01

    The Chlamydiales are an order of obligate intracellular bacteria sharing a developmental cycle inside a cytosolic vacuole, with very diverse natural hosts, from amoebae to mammals. The clinically most important species is Chlamydia trachomatis. Many uncertainties remain as to how Chlamydia organizes its intracellular development and replication. The discovery of new Chlamydiales species from other families permits the comparative analysis of cell-biological events and may indicate events that are common to all or peculiar to some species and more or less tightly linked to "chlamydial" development. We used this approach in the infection of human cells with Waddlia chondrophila, a species from the family Waddliaceae whose natural host is uncertain. Compared to C. trachomatis, W. chondrophila had slightly different growth characteristics, including faster cytotoxicity. The embedding in cytoskeletal structures was not as pronounced as for the C. trachomatis inclusion. C. trachomatis infection generates proteolytic activity by the protease Chlamydia protease-like activity factor (CPAF), which degrades host substrates upon extraction; these substrates were not cleaved in the case of W. chondrophila. Unlike Chlamydia, W. chondrophila did not protect against staurosporine-induced apoptosis. C. trachomatis infection causes Golgi apparatus fragmentation and redirects post-Golgi sphingomyelin transport to the inclusion; both were absent from W. chondrophila-infected cells. When host cells were infected with both species, growth of both species was reduced. This study highlights differences between bacterial species that both depend on obligate intracellular replication inside an inclusion. Some features seem principally dispensable for intracellular development of Chlamydiales in vitro but may be linked to host adaptation of Chlamydia and the higher virulence of C. trachomatis.

  13. Detection of Chlamydia pneumoniae and Chlamydia psittaci in sputum samples by PCR.

    OpenAIRE

    Tong, C Y; Sillis, M

    1993-01-01

    AIMS--To use the polymerase chain reaction (PCR) to detect Chlamydia pneumoniae and Chlamydia psittaci in sputum samples. METHODS--A nested PCR was developed, the first stage of which amplified DNA from both C pneumoniae and C psittaci while the second stage targeted specifically at C pneumoniae, allowing the two species to be differentiated. The primers were designed not to amplify sequences from C trachomatis. A panel of 26 sputum samples from patients with community acquired pneumonia eval...

  14. Effect of the purinergic receptor P2X7 on Chlamydia infection in cervical epithelial cells and vaginally infected mice.

    Science.gov (United States)

    Darville, Toni; Welter-Stahl, Lynn; Cruz, Cristiane; Sater, Ali Abdul; Andrews, Charles W; Ojcius, David M

    2007-09-15

    Ligation of the purinergic receptor, P2X7R, with its agonist ATP has been previously shown to inhibit intracellular infection by chlamydiae and mycobacteria in macrophages. The effect of P2X7R on chlamydial infection had never been investigated in the preferred target cells of chlamydiae, cervical epithelial cells, nor in vaginally infected mice. In this study, we show that treatment of epithelial cells with P2X7R agonists inhibits partially Chlamydia infection in epithelial cells. Chelation of ATP with magnesium or pretreatment with a P2X7R antagonist blocks the inhibitory effects of ATP. Similarly to previous results obtained with macrophages, ATP-mediated inhibition of infection in epithelial cells requires activation of host-cell phospholipase D. Vaginal infection was also more efficient in P2X7R-deficient mice, which also displayed a higher level of acute inflammation in the endocervix, oviduct, and mesosalpingeal tissues than in infected wild-type mice. However, secretion of IL-1beta, which requires P2X7R ligation during infection by other pathogens, was decreased mildly and only at short times of infection. Taken together, these results suggest that P2X7R affects Chlamydia infection by directly inhibiting infection in epithelial cells, rather than through the ability of P2X7R to modulate IL-1beta secretion.

  15. The trans-Golgi SNARE syntaxin 10 is required for optimal development of Chlamydia trachomatis

    Directory of Open Access Journals (Sweden)

    Andrea L Lucas

    2015-09-01

    Full Text Available Chlamydia trachomatis, an obligate intracellular pathogen, grows inside of a vacuole, termed the inclusion. Within the inclusion, the organisms differentiate from the infectious elementary body (EB into the reticulate body (RB. The RB communicates with the host cell through the inclusion membrane to obtain the nutrients necessary to divide, thus expanding the chlamydial population. At late time points within the developmental cycle, the RBs respond to unknown molecular signals to redifferentiate into infectious EBs to perpetuate the infection cycle. One strategy for Chlamydia to obtain necessary nutrients and metabolites from the host is to intercept host vesicular trafficking pathways. In this study we demonstrate that a trans-Golgi soluble N-ethylmaleimide–sensitive factor attachment protein (SNARE, syntaxin 10, and/or syntaxin10-associated Golgi elements colocalize with the chlamydial inclusion. We hypothesized that Chlamydia utilizes the molecular machinery of syntaxin 10 at the inclusion membrane to intercept specific vesicular trafficking pathways in order to create and maintain an optimal intra-inclusion environment. To test this hypothesis, we used siRNA knockdown of syntaxin 10 to examine the impact of the loss of syntaxin 10 on chlamydial growth and development. Our results demonstrate that loss of syntaxin 10 leads to defects in normal chlamydial maturation including: variable inclusion size with fewer chlamydial organisms per inclusion, fewer infectious progeny, and delayed or halted RB-EB differentiation. These defects in chlamydial development correlate with an overabundance of NBD-lipid retained by inclusions cultured in syntaxin 10 knockdown cells. Overall, loss of syntaxin 10 at the inclusion membrane negatively affects Chlamydia. Understanding host machinery involved in maintaining an optimal inclusion environment to support chlamydial growth and development is critical towards understanding the molecular signals involved in

  16. Chlamydia Pneumoniae Pneumonia: An Evolving Clinical Spectrum

    Directory of Open Access Journals (Sweden)

    David Megran

    1995-01-01

    Full Text Available Chlamydia pneumoniae is a recently recognized respiratory tract pathogen. It accounts for 6 to 10% of all cases of community acquired pneumonia requiring admission to hospital. Two patients hospitalized with C pneumoniae pneumonia are presented to illustrate its range of severity and the extrapulmonary manifestations.

  17. Chlamydia pneumoniae pneumonia: An evolving clinical spectrum

    Science.gov (United States)

    Megran, David; Peeling, Rosanna W; Marrie, Thomas J

    1995-01-01

    Chlamydia pneumoniae is a recently recognized respiratory tract pathogen. It accounts for 6 to 10% of all cases of community acquired pneumonia requiring admission to hospital. Two patients hospitalized with C pneumoniae pneumonia are presented to illustrate its range of severity and the extrapulmonary manifestations. PMID:22514396

  18. Molecular biology of the Chlamydia pneumoniae surface

    DEFF Research Database (Denmark)

    Christiansen, Gunna; Østergaard, Lars; Birkelund, Svend

    1997-01-01

    Chlamydia pneumoniaeis a fastidious microorganism with a characteristic biphasic lifecycle causing a variety of human respiratory tract infections. There is limited knowledge about the molecular biology of C. pneumoniae, and only a few genes have been sequenced. The structure of the chlamydial...

  19. CHLAMYDIA TRACHOMATIS: TRANSMISION VERTICAL CON MEMBRANAS INTEGRAS

    OpenAIRE

    2002-01-01

    Se presenta un caso clínico de transmisión vertical de Chlamydia trachomatis con membranas amniocoriónicas íntegras. Se discute esta rara vía de contagio realizando una revisión actualizada de su diagnóstico y tratamiento

  20. Chlamydia Infections - Multiple Languages: MedlinePlus

    Science.gov (United States)

    ... sharing features on this page, please enable JavaScript. Amharic (amarunya) Chinese - Simplified (简体中文) Chinese - Traditional (繁體中文) Oromo (Afaan Oromo) Spanish (español) Amharic (amarunya) Chlamydia English amarunya (Amharic) PDF Minnesota Department ...

  1. Chemical cross-linking of Chlamydia trachomatis

    DEFF Research Database (Denmark)

    Birkelund, Svend; Lundemose, AG; Christiansen, Gunna

    1988-01-01

    Purified elementary bodies (EBs) of Chlamydia trachomatis serovar L2 were analyzed by chemical cross-linking with disuccinimidyl selenodipropionate. The effect of the cross-linking was analyzed by immunoblotting sodium dodecyl sulfate-polyacrylamide gel electrophoresis-separated components which...

  2. Population-level intervention to promote chlamydia screening. Moving toward implementation of chlamydia hedis 2000 measure

    Science.gov (United States)

    Oh; Grimley; Heudebert

    2000-05-01

    Background: HEDIS 2000 measure includes chlamydia screening in women which is designed to assess the percentage of sexually active women 15 to 25 years who have received at least one screening test for chlamydia during the reporting year. This study is being undertaken to determine feasibility of implementing a population-level intervention within HMOs to promote chlamydia screening. This abstract presents preliminary findings from the Birmingham project of this multicenter study.Methods: In partnerships with two HMOs, series of outreach methods were used in a stepwise fashion to determine potential barriers and enabling factors for the implementation of chlamydia HEDIS measure in a conservative social environment. Mail outreach was sequentially combined with newspaper, TV, radio advertisements and poster displays. Both qualitative and quantitative impact of the outreach efforts were measured across the timeline. The measures included reporting for chlamydia screening (urine LCR) and infection rate, monitoring chlamydia hotline and staffed phoneline use, and assessment of untoward effects and cost-analysis of the chlamydia outreach campaign.Results: The key findings are: the benefit of chlamydia screening is not understood by general public, letters send by Health Plans to their members are not read by many subscribers, and there are wide gaps between adolescents and their parents, in knowledge, attitudes, beliefs in regard to obtaining information and accessing the screening services (teens prefer hotline, brochure in an envelop addressed to teens, incentives for reporting to the clinic for screening, vs. parents prefer staffed phone consults, "exposed" brochure addressed to parents, and no incentives). A month of sustained and repeat multi-media campaign resulted in 330 hotline calls, 83 phone calls and only 17 subjects being tested (3 were positive) though many more intended to come. Cumulative effects and cost of various outreach efforts are being monitored

  3. B cells enhance antigen-specific CD4 T cell priming and prevent bacteria dissemination following Chlamydia muridarum genital tract infection.

    Science.gov (United States)

    Li, Lin-Xi; McSorley, Stephen J

    2013-10-01

    B cells can contribute to acquired immunity against intracellular bacteria, but do not usually participate in primary clearance. Here, we examined the endogenous CD4 T cell response to genital infection with Chlamydia muridarum using MHC class-II tetramers. Chlamydia-specific CD4 T cells expanded rapidly and persisted as a stable memory pool for several months after infection. While most lymph node Chlamydia-specific CD4 T cells expressed T-bet, a small percentage co-expressed Foxp3, and RORγt-expressing T cells were enriched within the reproductive tract. Local Chlamydia-specific CD4 T cell priming was markedly reduced in mice lacking B cells, and bacteria were able to disseminate to the peritoneal cavity, initiating a cellular infiltrate and ascites. However, bacterial dissemination also coincided with elevated systemic Chlamydia-specific CD4 T cell responses and resolution of primary infection. Together, these data reveal heterogeneity in pathogen-specific CD4 T cell responses within the genital tract and an unexpected requirement for B cells in regulating local T cell activation and bacterial dissemination during genital infection.

  4. A Co-infection Model System and the Use of Chimeric Proteins to Study Chlamydia Inclusion Proteins Interaction

    Science.gov (United States)

    Han, Ying; Derré, Isabelle

    2017-01-01

    Chlamydia trachomatis is an obligate intracellular bacterium associated with trachoma and sexually transmitted diseases. During its intracellular developmental cycle, Chlamydia resides in a membrane bound compartment called the inclusion. A subset of Type III secreted effectors, the inclusion membrane proteins (Inc), are inserted into the inclusion membrane. Inc proteins are strategically positioned to promote inclusion interaction with host factors and organelles, a process required for bacterial replication, but little is known about Inc proteins function or host interacting partners. Moreover, it is unclear whether each Inc protein has a distinct function or if a subset of Inc proteins interacts with one another to perform their function. Here, we used IncD as a model to investigate Inc/Inc interaction in the context of Inc protein expression in C. trachomatis. We developed a co-infection model system to display different tagged Inc proteins on the surface of the same inclusion. We also designed chimeric Inc proteins to delineate domains important for interaction. We showed that IncD can self-interact and that the full-length protein is required for dimerization and/or oligomerization. Altogether our approach can be generalized to any Inc protein and will help to characterize the molecular mechanisms by which Chlamydia Inc proteins interact with themselves and/or host factors, eventually leading to a better understanding of C. trachomatis interaction with the mammalian host. PMID:28352612

  5. The early gene product EUO is a transcriptional repressor that selectively regulates promoters of Chlamydia late genes.

    Science.gov (United States)

    Rosario, Christopher J; Tan, Ming

    2012-06-01

    The obligate intracellular bacterium Chlamydia has an unusual developmental cycle in which there is conversion between two forms that are specialized for either intracellular replication or propagation of the infection to a new host cell. Expression of late chlamydial genes is upregulated during conversion from the replicating to the infectious form, but the mechanism for this temporal regulation is unknown. We found that EUO, which is expressed from an early gene, binds to two sites upstream of the late operon omcAB, but only the downstream site was necessary for transcriptional repression. Using gel shift and in vitro transcription assays we showed that EUO specifically bound and repressed promoters of Chlamydia trachomatis late genes, but not early or mid genes. These findings support a role for EUO as a temporal repressor that negatively regulates late chlamydial genes and prevents their premature expression. The basis of this specificity is the ability of EUO to selectively bind promoter regions of late genes, which would prevent their transcription by RNA polymerase. Thus, we propose that EUO is a master regulator that prevents the terminal differentiation of the replicating form of chlamydiae into the infectious form until sufficient rounds of replication have occurred.

  6. Effect of Ureaplasma parvum co-incubation on Chlamydia trachomatis maturation in human epithelial HeLa cells treated with interferon-γ.

    Science.gov (United States)

    Yamazaki, Tomohiro; Matsuo, Junji; Nakamura, Shinji; Oguri, Satoshi; Yamaguchi, Hiroyuki

    2014-08-01

    Chlamydia trachomatis is an obligate intracellular bacterium that causes a sexually transmitted disease. Ureaplasma parvum is commensal in the human genital tract, with a minimal contribution to urogenital infection. We have recently found that U. parvum has a significant effect on the presence of C. trachomatis in the genital tract of healthy women. We therefore assessed the effect of U. parvum co-incubation on C. trachomatis maturation from reticulate bodies (RBs) to elementary bodies (EBs) in HeLa cells in the absence or presence of interferon (IFN)-γ, which is a critical host defense factor. IFN-γ stimulation of viable U. parvum significantly prompted chlamydial growth with an increase in infectious particles, EBs, in HeLa cells. IFN-γ treatment of killed U. parvum had a similar effect on C. trachomatis maturation in HeLa cells. There was no change in expression of indoleamine 2,3-dioxygenase (IDO) in cultures of viable or killed U. parvum. We concluded that U. parvum co-incubation by IFN-γ helped C. trachomatis to mature from RBs to EBs in HeLa cells, independent of IDO expression. This suggests a novel survival strategy of C. trachomatis against IFN-γ exposure, prompting secondary infection of the genital mucosa, with possible clinical implications.

  7. {sup 99m}Tc reduces clonogenic survival after intracellular uptake in NIS positive cells in vitro more than {sup 131}I; {sup 99m}Tc reduziert nach intrazellulaerer Aufnahme in NIS-positiven Zellen in vitro das klonogene Ueberleben staerker als {sup 131}I

    Energy Technology Data Exchange (ETDEWEB)

    Wendisch, M.; Freudenberg, R.; Drechsel, J.; Runge, R.; Wunderlich, G.; Kotzerke, Joerg [Universitaetsklinikum Carl Gustav Carus Dresden - Technische Univ. Dresden (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    2010-07-01

    In addition to gamma radiation of 140 keV {sup 99m}Tc emits during the transition to {sup 99}Tc electrons of low energy and tiny path-lengths. These Auger electrons cannot be utilized in diagnostic procedures. However, they were discussed frequently for therapeutic application. Hitherto proof of effect of the Auger electrons from {sup 99m}Tc is missing which is supplied now in an in vitro-system in comparison to beta-emitter {sup 131}I. The thyroid cell line PC CI3 (sodium iodide symporter (NIS)-positive) was incubated with {sup 131}I-sodium iodide ({sup 131}I) or {sup 99m}Tc-pertechnetate ({sup 99m}Tc) in presence or absence of perchlorate. For comparison the amount of radioactivity was adjusted to obtain the same dose from extracellular irradiation for both radionuclides. The colony forming assay detects the clonogenic cell survival as surviving fraction. In addition, intracellular radionuclide uptake was quantified. Dose effect curves were established for {sup 131}I and {sup 99m}Tc for variable extra- and intracellular distribution of the radioactivity. In presence of perchlorate no cellular uptake of radioactivity was detectable. Survival curves were largely comparable confirming the dosimetric calculations. In absence of perchlorate cellular radiotracer uptake varied from 1.39% ({sup 131}I) to 1.90% ({sup 99m}Tc). Effects on survival were twice for the beta-emitter and ten-fold higher for {sup 99m}Tc. Intracellular uptake of {sup 131}I and {sup 99m}Tc increases DNA-damage compared to strict extracellular radiotracer distribution which was demonstrated by means of colony forming assay. Increasing radiotoxicity from intracellular {sup 99m}Tc is explained most likely by increased dose deposition in cellular structures due to Auger- und conversion-electrons of low range and high local energy deposition. (orig.)

  8. Lipid rafts, caveolae, caveolin-1, and entry by Chlamydiae into host cells.

    Science.gov (United States)

    Stuart, Elizabeth S; Webley, Wilmore C; Norkin, Leonard C

    2003-07-01

    Obligate intracellular bacterial pathogens of the genus Chlamydia are reported to enter host cells by both clathrin-dependent and clathrin-independent processes. C. trachomatis serovar K recently was shown to enter cells via caveolae-like lipid raft domains. We asked here how widespread raft-mediated entry might be among the Chlamydia. We show that C. pneumoniae, an important cause of respiratory infections in humans that additionally is associated with cardiovascular disease, and C. psittaci, an important pathogen in domestic mammals and birds that also infects humans, each enter host cells via cholesterol-rich lipid raft microdomains. Further, we show that C. trachomatis serovars E and F also use these domains to enter host cells. The involvement of these membrane domains in the entry of these organisms was indicated by the sensitivity of their entry to the raft-disrupting agents Nystatin and filipin, and by their intracellular association with caveolin-1, a 22-kDa protein associated with the formation of caveolae in rafts. In contrast, caveolin-marked lipid raft domains do not mediate entry of C. trachomatis serovars A, 36B, and C, nor of LGV serovar L2 and MoPn. Finally, we show that entry of each of these chlamydial strains is independent of cellular expression of caveolin-1. Thus, entry via the Nystatin and filipin-sensitive pathway is dependent on lipid rafts containing cholesterol, rather than invaginated caveolae per se.

  9. Chlamydia trachomatis: milestones in clinical and microbiological diagnostics in the last hundred years: a review.

    Science.gov (United States)

    Budai, Irén

    2007-03-01

    Chlamydia trachomatis an obligate intracellular, Gram-negative bacterium is the causative agent of several acute or chronic, local and systemic human diseases such as trachoma, oculogenital and neonatal infections. It was discovered in 1907 by Halberstaedter and von Prowazek who observed it in conjunctival scrapings from an experimentally infected orangutan. In the last hundred years the detection and study of the intracellular pathogens, including chlamydiae, passed through an enormous evolution. This memorial review is dedicated to these important research and diagnostic discoveries and to the scientists who significantly contributed to this evolution starting from the application of simple light microscopy through the cell culture technique, antibiotic susceptibility, antigen and antibody detection, serotyping, to the real-time nucleic acid amplification and restriction fragment lengths polymorphism analysis. Although the majority of these old and new excellent diagnostic methods have been introduced into the rutine practice, the trachoma has remained one of the leading causes of blindness, and oculogenital chlamydial infections still are the most frequent sexually transmitted bacterial diseases, furthermore lymphogranuloma venereum is a disease emerging in the developed countries at the beginning of the 21 st century.

  10. Chlamydia trachomatis Is Resistant to Inclusion Ubiquitination and Associated Host Defense in Gamma Interferon-Primed Human Epithelial Cells

    Science.gov (United States)

    Haldar, Arun K.; Piro, Anthony S.; Finethy, Ryan; Espenschied, Scott T.; Brown, Hannah E.; Giebel, Amanda M.; Frickel, Eva-Maria; Nelson, David E.

    2016-01-01

    ABSTRACT The cytokine gamma interferon (IFN-γ) induces cell-autonomous immunity to combat infections with intracellular pathogens, such as the bacterium Chlamydia trachomatis. The present study demonstrates that IFN-γ-primed human cells ubiquitinate and eliminate intracellular Chlamydia-containing vacuoles, so-called inclusions. We previously described how IFN-γ-inducible immunity-related GTPases (IRGs) employ ubiquitin systems to mark inclusions for destruction in mouse cells and, furthermore, showed that the rodent pathogen Chlamydia muridarum blocks ubiquitination of its inclusions by interfering with mouse IRG function. Here, we report that ubiquitination of inclusions in human cells is independent of IRG and thus distinct from the murine pathway. We show that C. muridarum is susceptible to inclusion ubiquitination in human cells, while the closely related human pathogen C. trachomatis is resistant. C. muridarum, but not C. trachomatis, inclusions attract several markers of cell-autonomous immunity, including the ubiquitin-binding protein p62, the ubiquitin-like protein LC3, and guanylate-binding protein 1. Consequently, we find that IFN-γ priming of human epithelial cells triggers the elimination of C. muridarum, but not C. trachomatis, inclusions. This newly described defense pathway is independent of indole-2,3-dioxygenase, a known IFN-γ-inducible anti-Chlamydia resistance factor. Collectively, our observations indicate that C. trachomatis evolved mechanisms to avoid a human-specific, ubiquitin-mediated response as part of its unique adaptation to its human host. PMID:27965446

  11. Chlamydia trachomatis in cervicitis and urethritis in women.

    Science.gov (United States)

    Paavonen, J; Vesterinen, E

    1982-01-01

    In the Scandinavian countries today, Chlamydia trachomatis seems to be the most important cause of sexually transmitted diseases. Although C. trachomatis is most prevalent in symptomatic women and in persons visiting venereal disease clinics, the asymptomatic carrier rate, particularly in young women, appears to be surprisingly high. In addition to young age and level of sexual activity, the use of oral contraceptives and the presence of cervical ectopy are important risk factors for chlamydial infection. Chlamydial cervicitis often is characterized by a hypertrophic follicular appearance, with severe edema, erythema, friability, and endocervical mucopurulent discharge. On colposcopy, an atypical transformation zone is frequently observed. Papanicolaou smears taken from C. trachomatis culture-positive patients often reveal benign atypias and dyskaryotic changes. C. trachomatis, therefore, being a venereally transmitted intracellular organism, may well play a role in the development of cervical intraepithelial neoplasia (CIN). Future studies on patients with cytological atypias, therefore, also should include tests for C. trachomatis. Prospective studies are needed to determine the natural history and outcome of C. trachomatis-associated atypias and their behavior after adequate therapy. A large proportion of C. trachomatis-infected women also are culture-positive from the urethra. The demonstration that C. trachomatis is a common causative agent of acute urethral syndrome (also called abacterial urethritis, dysuria-pyuria syndrome) in women has been a valuable contribution. The diagnosis of pyuria in a patient with abacterial dysuria is of critical importance, since it suggests a chlamydial etiology and thus is a potentially treatable condition.

  12. Chlamydia trachomatis Mip-like protein

    DEFF Research Database (Denmark)

    Lundemose, AG; Rousch, DA; Birkelund, Svend

    1992-01-01

    A 27 kDa Chlamydia trachomatis Mip-like protein with homology of a 175-amino-acid C-terminal fragment to the surface-exposed Legionella pneumophila mip-gene product has previously been described. In this paper the entire chlamydia Mip-like sequence of C. trachomatis serovar L2 (lymphogranuloma...... venereum (LGV) biovar) is presented. The sequence shows high similarity to the legionella Mip protein and its C-terminal region, like that of the legionella Mip, has high amino acid similarity to eukaryotic and prokaryotic FK506-binding proteins. The chlamydial mip-like gene was detected by polymerase...... chain reaction (PCR) in other C. trachomatis serovars and by sequencing of the mip-like genes of serovars B and E (trachoma biovar) was shown to be highly conserved within the two major biovars of C. trachomatis. Monoclonal and polyclonal antibodies raised against the recombinant Mip-like protein failed...

  13. Chlamydia trachomatis in pelvic inflammatory disease.

    Science.gov (United States)

    Shrikhande, S N; Joshi, S G; Zodpey, S P; Saoji, A M

    1995-04-01

    The prevalence of genital Chlamydia trachomatis infection and some epidemiologic factors associated with it were studied in 273 pelvic inflammatory disease (PID) patients attending Gynaecologic clinic, Government Medical College, Nagpur. For detection of chlamydial antigen Pharmacia Diagnostics Chlamydia EIA test was used. This study revealed an overall positivity rate of 33% for C. trachomatis infection in PID patients. Of the hypothesised risk factors low socioeconomic status, history of sexual contacts with multiple partners and use of intrauterine devices (IUD) were significantly associated with C. trachomatis infections. However, use of oral contraceptives, barrier contraceptives and increasing age were found to be protective factors for C. trachomatis infection. Thus considering the significant contribution of C. trachomatis in etiology of PID and its independent association with some epidemiologic risk factors, extensive epidemiologic measures are recommended for prevention of these infections.

  14. Laboratory diagnosis of Chlamydia pneumoniae infections

    OpenAIRE

    Peeling, Rosanna W

    1995-01-01

    Chlamydia pneumoniae is an important cause of respiratory illness. There is a need for accurate and rapid laboratory diagnostic methods that will lead to improved patient care, appropriate use of antimicrobial therapy and a better understanding of the epidemiology of this emerging pathogen. Culture is highly specific but is technically demanding, expensive, has a long turnaround time and its sensitivity is highly dependent on transport conditions. Antigen detection tests such as enzyme immuno...

  15. [Morphological semen changes in Chlamydia trachomatis infection].

    Science.gov (United States)

    Maciejewski, Z; Dziecielski, H; Swierczyński, W; Semmler, G

    1989-06-01

    Semen was examined in 150 men patients of the Andrology Clinic for demonstration of Chlamydia trachomatis and for analysis of the effect of this infection on semen quality depression. A correlation was noted between the degree of infection (large number of organisms per field of vision) and such changes as cryptozoospermia, azoospermia, asthenozoospermia, teratozoospermia, oligoasthenozoospermia, asthenoteratozoospermia. Of interest was a high proportion of infection (56%) with Ch. trachomatis in this group.

  16. Chlamydia pneumoniae and atherosclrerosis: pathogenic ways

    OpenAIRE

    Woolcott, Orison; Facultad de Medicina, Universidad Nacional Mayor de San Marcos; Sánchez, Luis; Facultad de Medicina, Universidad Nacional Mayor de San Marcos

    2013-01-01

    Atherosclerosis is a chronic inflammatory process in which macrophages, smooth muscle cells, T lymphocytes, and several chemical mediators intervene. In recent years, the finding of Chlamydia pneumoniae in arterial atherosclerotic plaques has suggested an etiological role; however, whether C. pneumoniae causes atherosclerosis or precipitates or favors atheroesclerosis progression remains uncertain. We review studies published on-line or available in Lima specialized libraries regarding C. pne...

  17. [Follicular conjunctivitis due to Chlamydia trachomatis].

    Science.gov (United States)

    Basualdo, J A; Huarte, L; Bautista, E; Niedfeld, G; Alfonso, G; Rosso, N; Geronés, M; Galeppi, I

    2001-01-01

    During two years (1997-1999) an investigation of possible infections of chlamydial etiology in outpatients with follicular conjunctivitis was carried out, through the use of specific assays. Fifty-seven selected patients with presumptive inclusion conjunctivitis were diagnosed by means of ophthalmoscopic examination and bilateral tarsal-conjunctiva swabbing for microorganisms. The possible presence of Chlamydia trachomatis was tested by immunofluorescence microscopy and isolation in cell culture of McCoy line. Of the 57 conjunctivitis patients screened, 37 (65%) proved to be positive by cell culture (CC) and 27 (47%) by direct immunofluorescence (IFD). A good agreement between the two assays was observed, where the CC was more sensitive than IFD. Of these 37 patients with chlamydial conjunctivitis, 23 (62%) were women, with over one-third of them ranging in age from 45 to 65 years. Their clinical records revealed an evolution period of 1 to 12 months. Eighteen (78%) of these women reported previous genital pathology, while 4 (29%) of the 14 men had a history of urethritis by Chlamydia trachomatis. A high frequency of follicular conjunctivitis by Chlamydia (65%) in the screened patients was observed, without any evidence of urogenital signs and symptoms at the moment of the study.

  18. Chlamydia trachomatis cervicitis in gynecologic outpatients.

    Science.gov (United States)

    Ripa, K T; Svensson, L; Mårdh, P A; Weström, L

    1978-12-01

    Symptoms suggestive of a lower genital tract infection (LGTI) are common complaints in women who consult gynecologists. Sexually transmitted microorganisms, such as Chlamydia trachomatis. Neisseria gonorrhoeae, and Trichomonas vaginalis, are responsible for a substantial proportion of LGTI. This study was performed to establish the frequency of LGTI caused by C trachomatis in women attending a gynecologic outpatient clinic. Of 170 women with LGTI, 32.9% harbored one or more of these organisms: C trachomatis was found in 19.3%, N gonorrhoeae in 4.7%, and T vaginalis in 25.9%. The results of the isolation studies were correlated with clinical signs and symptoms. In women under 25 years of age, chlamydial cervicitis was found significantly more often in users of oral contraceptives than in nonusers. In women not taking such drugs, cervical erosion was found more often in Chlamydia-positive than Chlamydia-negative women. Since clinical examination failed to reveal any characteristic signs in cases of chlamydial infection, it was not possible to distinguish a chlamydial from a gonococcal infection. This study also reports the successful treatment of 15 women affected by chlamydial cervicitis with doxycycline or trimethoprim sulphamethoxazole.

  19. Promiscuous and adaptable enzymes fill "holes" in the tetrahydrofolate pathway in Chlamydia species.

    Science.gov (United States)

    Adams, Nancy E; Thiaville, Jennifer J; Proestos, James; Juárez-Vázquez, Ana L; McCoy, Andrea J; Barona-Gómez, Francisco; Iwata-Reuyl, Dirk; de Crécy-Lagard, Valérie; Maurelli, Anthony T

    2014-07-08

    Folates are tripartite molecules comprising pterin, para-aminobenzoate (PABA), and glutamate moieties, which are essential cofactors involved in DNA and amino acid synthesis. The obligately intracellular Chlamydia species have lost several biosynthetic pathways for essential nutrients which they can obtain from their host but have retained the capacity to synthesize folate. In most bacteria, synthesis of the pterin moiety of folate requires the FolEQBK enzymes, while synthesis of the PABA moiety is carried out by the PabABC enzymes. Bioinformatic analyses reveal that while members of Chlamydia are missing the genes for FolE (GTP cyclohydrolase) and FolQ, which catalyze the initial steps in de novo synthesis of the pterin moiety, they have genes for the rest of the pterin pathway. We screened a chlamydial genomic library in deletion mutants of Escherichia coli to identify the "missing genes" and identified a novel enzyme, TrpFCtL2, which has broad substrate specificity. TrpFCtL2, in combination with GTP cyclohydrolase II (RibA), the first enzyme of riboflavin synthesis, provides a bypass of the first two canonical steps in folate synthesis catalyzed by FolE and FolQ. Notably, TrpFCtL2 retains the phosphoribosyl anthranilate isomerase activity of the original annotation. Additionally, we independently confirmed the recent discovery of a novel enzyme, CT610, which uses an unknown precursor to synthesize PABA and complements E. coli mutants with deletions of pabA, pabB, or pabC. Thus, Chlamydia species have evolved a variant folate synthesis pathway that employs a patchwork of promiscuous and adaptable enzymes recruited from other biosynthetic pathways. Importance: Collectively, the involvement of TrpFCtL2 and CT610 in the tetrahydrofolate pathway completes our understanding of folate biosynthesis in Chlamydia. Moreover, the novel roles for TrpFCtL2 and CT610 in the tetrahydrofolate pathway are sophisticated examples of how enzyme evolution plays a vital role in the

  20. 21 CFR 866.3120 - Chlamydia serological reagents.

    Science.gov (United States)

    2010-04-01

    ... identification aids in the diagnosis of disease caused by bacteria belonging to the genus Chlamydia and provides epidemiological information on these diseases. Chlamydia are the causative agents of psittacosis (a form of pneumonia), lymphogranuloma venereum (a venereal disease), and trachoma (a chronic disease of the eye...

  1. Plaque formation by and plaque cloning of Chlamydia trachomatis biovar trachoma.

    Science.gov (United States)

    Matsumoto, A; Izutsu, H; Miyashita, N; Ohuchi, M

    1998-10-01

    A new technique for the induction of plaque formation by Chlamydia trachomatis biovar trachoma applicable to the titration of infectivity and cloning of biovar trachoma was established. Three novel strains were cloned and confirmed to be free of glycogen inclusions. The lack of glycogen accumulation correlated with the absence of a 7.5-kb plasmid, which is highly conserved in other strains of C. trachomatis. Although the growth efficiency of these plasmid-free strains was slightly lower than that of plasmid-positive strains, possession of the plasmid and glycogen accumulation were not essential for the survival of C. trachomatis.

  2. An atypical CD8 T-cell response to Chlamydia muridarum genital tract infections includes T cells that produce interleukin-13.

    Science.gov (United States)

    Johnson, Raymond M; Kerr, Micah S; Slaven, James E

    2014-06-01

    Chlamydia trachomatis urogenital serovars D-K are intracellular bacterial pathogens that replicate almost exclusively in human reproductive tract epithelium. In the C. muridarum mouse model for human Chlamydia genital tract infections CD4 T helper type 1 cell responses mediate protective immunity while CD8 T-cell responses have been associated with scarring and infertility. Scarring mediated by CD8 T cells requires production of tumour necrosis factor-α (TNF-α); however, TNF-α is associated with protective immunity mediated by CD4 T cells. The latter result suggests that TNF-α in-and-of itself may not be the sole determining factor in immunopathology. CD8 T cells mediating immunopathology presumably do something in addition to producing TNF-α that is detrimental during resolution of genital tract infections. To investigate the mechanism underlying CD8 immunopathology we attempted to isolate Chlamydia-specific CD8 T-cell clones from mice that self-cleared genital tract infections. They could not be derived with antigen-pulsed irradiated naive splenocytes; instead derivation required use of irradiated immune splenocyte antigen-presenting cells. The Chlamydia-specific CD8 T-cell clones had relatively low cell surface CD8 levels and the majority were not restricted by MHC class Ia molecules. They did not express Plac8, and had varying abilities to terminate Chlamydia replication in epithelial cells. Two of the five CD8 clones produced interleukin-13 (IL-13) in addition to IL-2, TNF-α, IL-10 and interferon-γ. IL-13-producing Chlamydia-specific CD8 T cells may contribute to immunopathology during C. muridarum genital tract infections based on known roles of TNF-α and IL-13 in scar formation.

  3. Detection of Chlamydia trachomatis in male and female urine specimens by using the amplified Chlamydia trachomatis test

    NARCIS (Netherlands)

    J.W. Mouton (Johan); R.P.A.J. Verkooyen (Roel); W.I. van der Meijden (Willem); T.H. van Rijsoort-Vos; W.H.F. Goessens (Wil); J.A.J.W. Kluytmans (Jan); S.D.A. Deelen (Sabine); A. Luijendijk (Ad); H.A. Verbrugh (Henri)

    1997-01-01

    textabstractThe amplified Chlamydia trachomatis test (AMP-CT; Gen-Probe), a new diagnostic test for the detection of Chlamydia trachomatis, was evaluated with urine specimens from 1,000 patients visiting the outpatient department for sexually transmitted diseases at the

  4. Improving the molecular diagnosis of Chlamydia psittaci and Chlamydia abortus infection with a species-specific duplex real-time PCR.

    Science.gov (United States)

    Opota, Onya; Jaton, Katia; Branley, James; Vanrompay, Daisy; Erard, Veronique; Borel, Nicole; Longbottom, David; Greub, Gilbert

    2015-10-01

    Chlamydia psittaci and Chlamydia abortus are closely related intracellular bacteria exhibiting different tissue tropism that may cause severe but distinct infection in humans. C. psittaci causes psittacosis, a respiratory zoonotic infection transmitted by birds. C. abortus is an abortigenic agent in small ruminants, which can also colonize the human placenta and lead to foetal death and miscarriage. Infections caused by C. psittaci and C. abortus are underestimated mainly due to diagnosis difficulties resulting from their strict intracellular growth. We developed a duplex real-time PCR to detect and distinguish these two bacteria in clinical samples. The first PCR (PCR1) targeted a sequence of the 16S-23S rRNA operon allowing the detection of both C. psittaci and C. abortus. The second PCR (PCR2) targeted the coding DNA sequence CPSIT_0607 unique to C. psittaci. The two PCRs showed 100 % detection for ≥ 10 DNA copies per reaction (1000 copies ml(- 1)). Using a set of 120 samples, including bacterial reference strains, clinical specimens and infected cell culture material, we monitored 100 % sensitivity and 100 % specificity for the detection of C. psittaci and C. abortus for PCR1. When PCR1 was positive, PCR2 could discriminate C. psittaci from C. abortus with a positive predictive value of 100 % and a negative predictive value of 88 %. In conclusion, this new duplex PCR represents a low-cost and time-saving method with high-throughput potential, expected to improve the routine diagnosis of psittacosis and pregnancy complication in large-scale screening programs and also during outbreaks.

  5. Chlamydia pneumoniae e doença aterosclerótica = Chlamydia pneumoniae and atherosclerotic disease

    Directory of Open Access Journals (Sweden)

    Sehnem, Luciele

    2010-01-01

    Conclusões: a infecção por Chlamydia pneumoniae pode constituir achado de importância etiopatogênica na ateromatose. Entretanto, a relevância clínica dessa associação, como mostram os estudos epidemiológicos e ensaios clínicos aqui revisados, ainda é incerta

  6. The lipid transfer protein CERT interacts with the Chlamydia inclusion protein IncD and participates to ER-Chlamydia inclusion membrane contact sites.

    Directory of Open Access Journals (Sweden)

    Isabelle Derré

    2011-06-01

    Full Text Available Bacterial pathogens that reside in membrane bound compartment manipulate the host cell machinery to establish and maintain their intracellular niche. The hijacking of inter-organelle vesicular trafficking through the targeting of small GTPases or SNARE proteins has been well established. Here, we show that intracellular pathogens also establish direct membrane contact sites with organelles and exploit non-vesicular transport machinery. We identified the ER-to-Golgi ceramide transfer protein CERT as a host cell factor specifically recruited to the inclusion, a membrane-bound compartment harboring the obligate intracellular pathogen Chlamydia trachomatis. We further showed that CERT recruitment to the inclusion correlated with the recruitment of VAPA/B-positive tubules in close proximity of the inclusion membrane, suggesting that ER-Inclusion membrane contact sites are formed upon C. trachomatis infection. Moreover, we identified the C. trachomatis effector protein IncD as a specific binding partner for CERT. Finally we showed that depletion of either CERT or the VAP proteins impaired bacterial development. We propose that the presence of IncD, CERT, VAPA/B, and potentially additional host and/or bacterial factors, at points of contact between the ER and the inclusion membrane provides a specialized metabolic and/or signaling microenvironment favorable to bacterial development.

  7. Metabolic features of Protochlamydia amoebophila elementary bodies--a link between activity and infectivity in Chlamydiae.

    Directory of Open Access Journals (Sweden)

    Barbara S Sixt

    Full Text Available The Chlamydiae are a highly successful group of obligate intracellular bacteria, whose members are remarkably diverse, ranging from major pathogens of humans and animals to symbionts of ubiquitous protozoa. While their infective developmental stage, the elementary body (EB, has long been accepted to be completely metabolically inert, it has recently been shown to sustain some activities, including uptake of amino acids and protein biosynthesis. In the current study, we performed an in-depth characterization of the metabolic capabilities of EBs of the amoeba symbiont Protochlamydia amoebophila. A combined metabolomics approach, including fluorescence microscopy-based assays, isotope-ratio mass spectrometry (IRMS, ion cyclotron resonance Fourier transform mass spectrometry (ICR/FT-MS, and ultra-performance liquid chromatography mass spectrometry (UPLC-MS was conducted, with a particular focus on the central carbon metabolism. In addition, the effect of nutrient deprivation on chlamydial infectivity was analyzed. Our investigations revealed that host-free P. amoebophila EBs maintain respiratory activity and metabolize D-glucose, including substrate uptake as well as host-free synthesis of labeled metabolites and release of labeled CO2 from (13C-labeled D-glucose. The pentose phosphate pathway was identified as major route of D-glucose catabolism and host-independent activity of the tricarboxylic acid (TCA cycle was observed. Our data strongly suggest anabolic reactions in P. amoebophila EBs and demonstrate that under the applied conditions D-glucose availability is essential to sustain metabolic activity. Replacement of this substrate by L-glucose, a non-metabolizable sugar, led to a rapid decline in the number of infectious particles. Likewise, infectivity of Chlamydia trachomatis, a major human pathogen, also declined more rapidly in the absence of nutrients. Collectively, these findings demonstrate that D-glucose is utilized by P. amoebophila

  8. Asymptomatic endemic Chlamydia pecorum infections reduce growth rates in calves by up to 48 percent.

    Directory of Open Access Journals (Sweden)

    Anil Poudel

    Full Text Available Intracellular Chlamydia (C. bacteria cause in cattle some acute but rare diseases such as abortion, sporadic bovine encephalomyelitis, kerato-conjunctivitis, pneumonia, enteritis and polyarthritis. More frequent, essentially ubiquitous worldwide, are low-level, asymptomatic chlamydial infections in cattle. We investigated the impact of these naturally acquired infections in a cohort of 51 female Holstein and Jersey calves from birth to 15 weeks of age. In biweekly sampling, we measured blood/plasma markers of health and infection and analyzed their association with clinical appearance and growth in dependence of chlamydial infection intensity as determined by mucosal chlamydial burden or contemporaneous anti-chlamydial plasma IgM. Chlamydia 23S rRNA gene PCR and ompA genotyping identified only C. pecorum (strains 1710S, Maeda, and novel strain Smith3v8 in conjunctival and vaginal swabs. All calves acquired the infection but remained clinically asymptomatic. High chlamydial infection associated with reduction of body weight gains by up to 48% and increased conjunctival reddening (P<10(-4. Simultaneously decreased plasma albumin and increased globulin (P<10(-4 suggested liver injury by inflammatory mediators as mechanisms for the growth inhibition. This was confirmed by the reduction of plasma insulin like growth factor-1 at high chlamydial infection intensity (P<10(-4. High anti-C. pecorum IgM associated eight weeks later with 66% increased growth (P = 0.027, indicating a potential for immune protection from C. pecorum-mediated growth depression. The worldwide prevalence of chlamydiae in livestock and their high susceptibility to common feed-additive antibiotics suggests the possibility that suppression of chlamydial infections may be a major contributor to the growth promoting effect of feed-additive antibiotics.

  9. Advances in genetic manipulation of obligate intracellular bacterial pathogens

    Directory of Open Access Journals (Sweden)

    Paul eBeare

    2011-05-01

    Full Text Available Infections by obligate intracellular bacterial pathogens result in significant morbidity and mortality worldwide. These bacteria include Chlamydia spp., which causes millions of cases of sexually transmitted disease and blinding trachoma annually, and members of the α-proteobacterial genera Anaplasma, Ehrlichia, Orientia and Rickettsia, agents of serious human illnesses including epidemic typhus. Coxiella burnetii, the agent of human Q fever, has also been considered a prototypical obligate intracellular bacterium, but recent host cell-free (axenic growth has rescued it from obligatism. The historic genetic intractability of obligate intracellular bacteria has severely limited molecular dissection of their unique lifestyles and virulence factors involved in pathogenesis. Host cell restricted growth is a significant barrier to genetic transformation that can make simple procedures for free-living bacteria, such as cloning, exceedingly difficult. Low transformation efficiency requiring long term culture in host cells to expand small transformant populations is another obstacle. Despite numerous technical limitations, the last decade has witnessed significant gains in genetic manipulation of obligate intracellular bacteria including allelic exchange. Continued development of genetic tools should soon enable routine mutation and complementation strategies for virulence factor discovery and stimulate renewed interest in these refractory pathogens. In this review, we discuss the technical challenges associated with genetic transformation of obligate intracellular bacteria and highlight advances made with individual genera.

  10. Members of the Pmp protein family of Chlamydia pneumoniae mediate adhesion to human cells via short repetitive peptide motifs.

    Science.gov (United States)

    Mölleken, Katja; Schmidt, Eleni; Hegemann, Johannes H

    2010-11-01

    Chlamydiae sp. are obligate intracellular pathogens that cause a variety of diseases in humans. Adhesion of the infectious elementary body to the eukaryotic host cell is a pivotal step in chlamydial pathogenesis. Here we describe the characterization of members of the polymorphic membrane protein family (Pmp), the largest protein family (with up to 21 members) unique to Chlamydiaceae. We show that yeast cells displaying Pmp6, Pmp20 or Pmp21 on their surfaces, or beads coated with the recombinant proteins, adhere to human epithelial cells. A hallmark of the Pmp protein family is the presence of multiple repeats of the tetrapeptide motifs FxxN and GGA(I, L, V) and deletion analysis shows that at least two copies of these motifs are needed for adhesion. Importantly, pre-treatment of human cells with recombinant Pmp6, Pmp20 or Pmp21 protein reduces infectivity upon subsequent challenge with Chlamydia pneumoniae and correlates with diminished attachment of Chlamydiae to target cells. Antibodies specific for Pmp21 can neutralize infection in vitro. Finally, a combination of two different Pmp proteins in infection blockage experiments shows additive effects, possibly suggesting similar functions. Our findings imply that Pmp6, Pmp20 and Pmp21 act as adhesins, are vital during infection and thus represent promising vaccine candidates.

  11. Uptake of biotin by Chlamydia Spp. through the use of a bacterial transporter (BioY and a host-cell transporter (SMVT.

    Directory of Open Access Journals (Sweden)

    Derek J Fisher

    Full Text Available Chlamydia spp. are obligate intracellular Gram-negative bacterial pathogens that cause disease in humans and animals. Minor variations in metabolic capacity between species have been causally linked to host and tissue tropisms. Analysis of the highly conserved genomes of Chlamydia spp. reveals divergence in the metabolism of the essential vitamin biotin with genes for either synthesis (bioF_2ADB and/or transport (bioY. Streptavidin blotting confirmed the presence of a single biotinylated protein in Chlamydia. As a first step in unraveling the need for divergent biotin acquisition strategies, we examined BioY (CTL0613 from C. trachomatis 434/Bu which is annotated as an S component of the type II energy coupling-factor transporters (ECF. Type II ECFs are typically composed of a transport specific component (S and a chromosomally unlinked energy module (AT. Intriguingly, Chlamydia lack recognizable AT modules. Using (3H-biotin and recombinant E. coli expressing CTL0613, we demonstrated that biotin was transported with high affinity (a property of Type II ECFs previously shown to require an AT module and capacity (apparent K(m of 3.35 nM and V(max of 55.1 pmol×min(-1×mg(-1. Since Chlamydia reside in a host derived membrane vacuole, termed an inclusion, we also sought a mechanism for transport of biotin from the cell cytoplasm into the inclusion vacuole. Immunofluorescence microscopy revealed that the mammalian sodium multivitamin transporter (SMVT, which transports lipoic acid, biotin, and pantothenic acid into cells, localizes to the inclusion. Since Chlamydia also are auxotrophic for lipoic and pantothenic acids, SMVT may be subverted by Chlamydia to move multiple essential compounds into the inclusion where BioY and another transporter(s would be present to facilitate transport into the bacterium. Collectively, our data validates the first BioY from a pathogenic organism and describes a two-step mechanism by which Chlamydia transport biotin

  12. Chlamydia in canine or feline coronary arteriosclerotic lesions

    Directory of Open Access Journals (Sweden)

    Grabarevic Zeljko

    2011-09-01

    Full Text Available Abstract Background There are numerous reports linking Chlamydia infection to human coronary atherosclerosis. However, there is a lack of data regarding this correlation in dogs and cats, and there are no reports investigating coronary arteriosclerosis and Chlamydia in these species. The aim of the present study was to examine whether there is a correlation between canine and feline spontaneous atherosclerosis or arteriosclerosis and the presence of Chlamydia. Archived histopathological samples of dogs (n = 16 and cats (n = 13 with findings of atherosclerosis or arteriosclerosis in heart tissue were examined for the presence of Chlamydiaceae using real-time PCR, ArrayTube Microarray and immunohistochemistry. Additionally, arteriosclerotic lesions of all cases were histologically classified and graded. Results Both canine atherosclerotic cases, and all 14 canine arteriosclerotic cases were negative for Chlamydia. Only one of the 13 arteriosclerotic feline cases was positive for Chlamydia by real-time PCR, revealing C. abortus by ArrayTube Microarray. To our knowledge, this is the first description of C. abortus in a cat. Overall, the type and grade of canine and feline arteriosclerotic lesions revealed similarities, and were predominantly moderate and hyperplastic. Conclusions These findings suggest that there is no obvious correlation between canine and feline coronary arteriosclerosis and the presence of Chlamydia. In order to draw final conclusions about the correlation between Chlamydia and canine atherosclerosis, examination of more samples is required.

  13. Genetic diversity of Chlamydia among captive birds from central Argentina.

    Science.gov (United States)

    Frutos, María C; Monetti, Marina S; Vaulet, Lucia Gallo; Cadario, María E; Fermepin, Marcelo Rodríguez; Ré, Viviana E; Cuffini, Cecilia G

    2015-01-01

    To study the occurrence of Chlamydia spp. and their genetic diversity, we analysed 793 cloacal swabs from 12 avian orders, including 76 genera, obtained from 80 species of asymptomatic wild and captive birds that were examined with conventional nested polymerase chain reaction and quantitative polymerase chain reaction. Chlamydia spp. were not detected in wild birds; however, four species (Chlamydia psittaci, Chlamydia pecorum, Chlamydia pneumoniae and Chlamydia gallinacea) were identified among captive birds (Passeriformes, n = 20; Psittaciformes, n = 15; Rheiformes, n = 8; Falconiformes n = 2; Piciformes n = 2; Anseriformes n = 1; Galliformes n = 1; Strigiformes n = 1). Two pathogens (C. pneumoniae and C. pecorum) were identified simultaneously in samples obtained from captive birds. Based on nucleotide-sequence variations of the ompA gene, three C. psittaci-positive samples detected were grouped into a cluster with the genotype WC derived from mammalian hosts. A single positive sample was phylogenetically related to a new strain of C. gallinacea. This report contributes to our increasing understanding of the abundance of Chlamydia in the animal kingdom.

  14. [Demonstration of Chlamydia from an equine abortion].

    Science.gov (United States)

    Henning, K; Sachse, K; Sting, R

    2000-02-01

    The isolation and identification of a chlamydial agent from an equine fetus is reported. The fetus was aborted by a mare with respiratory disease and fever in the 9th month of pregnancy. The serum of the mare was investigated by the compliment fixation test. Specific antibodies were detected for chlamydial antigen in a titer of > 1:40 and for equine herpes virus 1 antigen in a titer of 1:32. Pathological lesions were not found in the organs of the fetus. Chlamydiae were detected in the placenta by ELISA and subsequently isolated by cell culture. Using PCR technique the agent was identified as Chlamydophila psittaci.

  15. Investigation and application in infecting animal models of Chlamydia trachomatis%沙眼衣原体感染动物模型的研究及应用

    Institute of Scientific and Technical Information of China (English)

    张莉(综述); 陈超群(审校)

    2016-01-01

    Chlamydia trachomatis can lead to severe pathologies following its infection in genital tract, which is a gram-neg-ative bacterium with obligate intracellular parasitism and an unique replication cycle. Seting up a suitable animal model will provide a supportive basis in investigation of Chlamydia trachomatis related pathogenic mechanism and vaccine develop-ment. Recently a number of animal models are used in resarch on Chlamydia trachomatis infection, such as the mouse, guinea pig and non-human primate animal and so on.%沙眼衣原体( Chlamydia trachomatis, Ct)是一种严格细胞内寄生且具有独特发育周期的革兰阴性菌,感染人类生殖道等部位后会引起严重病理损伤。关于Ct感染人类宿主细胞的具体致病机制及疫苗的研制还有待深入研究。动物模型在Ct的基础研究方面具有较高的科研应用价值。就常见的小鼠、豚鼠、灵长类等Ct感染动物模型及应用作一综述。

  16. Intracellular Bacteria in Protozoa

    Science.gov (United States)

    Görtz, Hans-Dieter; Brigge, Theo

    Intracellular bacteria in humans are typically detrimental, and such infections are regarded by the patients as accidental and abnormal. In protozoa it seems obvious that many bacteria have coevolved with their hosts and are well adapted to the intracellular way of life. Manifold interactions between hosts and intracellular bacteria are found, and examples of antibacterial resistance of unknown mechanisms are observed. The wide diversity of intracellular bacteria in protozoa has become particularly obvious since they have begun to be classified by molecular techniques. Some of the bacteria are closely related to pathogens; others are responsible for the production of toxins.

  17. Penicillin kills Chlamydia following the fusion of bacteria with lysosomes and prevents genital inflammatory lesions in C. muridarum-infected mice.

    Science.gov (United States)

    Dumoux, Maud; Le Gall, Sylvain M; Habbeddine, Mohamed; Delarbre, Christiane; Hayward, Richard D; Kanellopoulos-Langevin, Colette; Verbeke, Philippe

    2013-01-01

    The obligate intracellular bacterium Chlamydia exists as two distinct forms. Elementary bodies (EBs) are infectious and extra-cellular, whereas reticulate bodies (RBs) replicate within a specialized intracellular compartment termed an 'inclusion'. Alternative persistent intra-cellular forms can be induced in culture by diverse stimuli such as IFNγ or adenosine/EHNA. They do not grow or divide but revive upon withdrawal of the stimulus and are implicated in several widespread human diseases through ill-defined in vivo mechanisms. β-Lactam antibiotics have also been claimed to induce persistence in vitro. The present report shows that upon penicillin G (pG) treatment, inclusions grow as fast as those in infected control cells. After removal of pG, Chlamydia do not revert to RBs. These effects are independent of host cell type, serovar, biovar and species of Chlamydia. Time-course experiments demonstrated that only RBs were susceptible to pG. pG-treated bacteria lost their control over host cell apoptotic pathways and no longer expressed pre-16S rRNA, in contrast to persistent bacteria induced with adenosine/EHNA. Confocal and live-video microscopy showed that bacteria within the inclusion fused with lysosomal compartments in pG-treated cells. That leads to recruitment of cathepsin D as early as 3 h post pG treatment, an event preceding bacterial death by several hours. These data demonstrate that pG treatment of cultured cells infected with Chlamydia results in the degradation of the bacteria. In addition we show that pG is significantly more efficient than doxycycline at preventing genital inflammatory lesions in C. muridarum-C57Bl/6 infected mice. These in vivo results support the physiological relevance of our findings and their potential therapeutic applications.

  18. Incidence of Chlamydia trachomatis infections in the provinces of Novara and VCO: one year of observations

    Directory of Open Access Journals (Sweden)

    Stefano Andreoni

    2009-12-01

    Full Text Available Chlamydia trachomatis infections represent the most common sexually transmitted diseases.The lack of growth of these microorganisms on common media and the roundabout research by immunofluorescence, has meant that, until now, these special-lived intracellular microorganisms have played a role probably underestimated in cases of infections affecting the sexual organs.The introduction of molecular biology has made possible their research in a much more simple, reliable and standardized methods. The study was carried out on endocervical samples, male urethral swabs and urine samples of men and women, determining the C. trachomatis DNA amplified using the BD ProbeTec ET system. This system uses technology SDA (Strand Displacement Amplification - Elongationcrowding of the blanks. The study was conducted from June 2008 to june 2009. Symptomatic and asyntptomatic patients residents in the provinces of Novara and the Verbano-Cusio-Ossola were considered. In this period 784 determinations were made in molecular biology. Chlamydia trachomatis was found in 26 cases equal to a percentage of 3.32%. While considering these preliminary data, however, we can estimate the rate of detection of C. trachomatis as a good starting point, because we have the impression that improved procedures particularly relate to the techniques for sampling and for storage and transport of the sample, can undoubtedly lead to much higher percentages.

  19. Binding of Galanthus nivalis lectin to Chlamydia trachomatis and inhibition of in vitro infection.

    Science.gov (United States)

    Amin, K; Beillevaire, D; Mahmoud, E; Hammar, L; Mårdh, P A; Fröman, G

    1995-10-01

    A glycoprotein present in Chlamydia trachomatis, serotype L1, elementary bodies (EBs) was earlier found to bind the lectin from Galanthus nivalis (GNA). In the present paper we investigate the interaction of GNA with chlamydial EBs and its effect on in vitro infectivity. The binding affinity was studied with 125I-GNA lectin. Within 15 min about 80% maximal binding was obtained. The chlamydia-GNA interaction was inhibited by alpha-methylmannoside, causing a decrease of about 50% at 1 mM. Curve fit analyses indicated two types of binding sites for GNA on the EBs. The affinity to these differed by a factor of 15. The influence of the lectin on the ability of C. trachomatis to infect McCoy cells was also investigated. There was a GNA-dependent inhibition with a 50% reduction in the number of intracellular inclusions at 0.2 microM of the lectin. The findings indicate the presence of terminal mannose structures on the chlamydial surface at or in the proximity of the cell-binding domains. Mannose-binding proteins of eukaryotic cells could be important for the initial uptake of EBs.

  20. Chlamydiaceae Genomics Reveals Interspecies Admixture and the Recent Evolution of Chlamydia abortus Infecting Lower Mammalian Species and Humans.

    Science.gov (United States)

    Joseph, Sandeep J; Marti, Hanna; Didelot, Xavier; Castillo-Ramirez, Santiago; Read, Timothy D; Dean, Deborah

    2015-10-27

    Chlamydiaceae are obligate intracellular bacteria that cause a diversity of severe infections among humans and livestock on a global scale. Identification of new species since 1989 and emergence of zoonotic infections, including abortion in women, underscore the need for genome sequencing of multiple strains of each species to advance our knowledge of evolutionary dynamics across Chlamydiaceae. Here, we genome sequenced isolates from avian, lower mammalian and human hosts. Based on core gene phylogeny, five isolates previously classified as Chlamydia abortus were identified as members of Chlamydia psittaci and Chlamydia pecorum. Chlamydia abortus is the most recently emerged species and is a highly monomorphic group that lacks the conserved virulence-associated plasmid. Low-level recombination and evidence for adaptation to the placenta echo evolutionary processes seen in recently emerged, highly virulent niche-restricted pathogens, such as Bacillus anthracis. In contrast, gene flow occurred within C. psittaci and other Chlamydiaceae species. The C. psittaci strain RTH, isolated from a red-tailed hawk (Buteo jamaicensis), is an outlying strain with admixture of C. abortus, C. psittaci, and its own population markers. An average nucleotide identity of less than 94% compared with other Chlamydiaceae species suggests that RTH belongs to a new species intermediary between C. psittaci and C. abortus. Hawks, as scavengers and predators, have extensive opportunities to acquire multiple species in their intestinal tract. This could facilitate transformation and homologous recombination with the potential for new species emergence. Our findings indicate that incubator hosts such as birds-of-prey likely promote Chlamydiaceae evolution resulting in novel pathogenic lineages.

  1. Intra-ChIP: studying gene regulation in an intracellular pathogen.

    Science.gov (United States)

    Hanson, Brett R; Tan, Ming

    2016-08-01

    Intracellular bacteria that reside within a host cell use a variety of strategies to exploit this unique niche. While these organisms are technically challenging to study in the context of an infected host cell, recent advances have led to an improved understanding of how the intracellular environment impacts bacterial gene expression. We recently demonstrated that chromatin immunoprecipitation (ChIP) can be used to quantify transcription factor binding in the obligate intracellular pathogen Chlamydia trachomatis within infected cells. Furthermore, we showed it was possible to experimentally modulate transcription factor binding while simultaneously measuring changes in transcription. Here we discuss these findings as well as other recent work that has used ChIP to study intracellular pathogens within infected cells. We also discuss technical considerations associated with this approach and its possible future applications.

  2. Risk of reproductive complications following chlamydia testing

    DEFF Research Database (Denmark)

    Davies, Bethan; Turner, Katy M E; Frølund, Maria;

    2016-01-01

    BACKGROUND: Uncertainty in the risk of reproductive complications (pelvic inflammatory disease, ectopic pregnancy, and tubal factor infertility) following chlamydia infection and repeat infection hampers the design of evidence-based chlamydia control programmes. We estimate the association between......, ectopic pregnancy, or tubal factor infertility. FINDINGS: The 516 720 women (103 344 positive, 182 879 negative, 230 497 never-tested) had a mean follow-up of 7·96 years. Compared with women with only negative tests, the risk of each complication was 30% higher in women with one or more positive tests...... (pelvic inflammatory disease, adjusted hazard ratio [AHR] 1·50 [95% CI 1·43-1·57]; ectopic pregnancy, AHR 1·31 [1·25-1·38]; tubal factor infertility, AHR 1·37 [1·24-1·52]) and 60% lower in women who were never-tested (pelvic inflammatory disease, AHR 0·33 [0·31-0·35]; ectopic pregnancy, AHR 0·42 [0...

  3. Failure to demonstrate Chlamydia pneumoniae in symptomatic abdominal aortic aneurysms by a nested polymerase chain reaction (PCR)

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal; Ostergård, L; Henneberg, E W;

    1998-01-01

    To investigate whether Chlamydia pneumoniae is present in symptomatic abdominal aortic aneurysms (AAA).......To investigate whether Chlamydia pneumoniae is present in symptomatic abdominal aortic aneurysms (AAA)....

  4. Chlamydia pneumoniae Infection in Atherosclerotic Lesion Development through Oxidative Stress: A Brief Overview

    Directory of Open Access Journals (Sweden)

    Rosa Sessa

    2013-07-01

    Full Text Available Chlamydia pneumoniae, an obligate intracellular pathogen, is known as a leading cause of respiratory tract infections and, in the last two decades, has been widely associated with atherosclerosis by seroepidemiological studies, and direct detection of the microorganism within atheroma. C. pneumoniae is presumed to play a role in atherosclerosis for its ability to disseminate via peripheral blood mononuclear cells, to replicate and persist within vascular cells, and for its pro-inflammatory and angiogenic effects. Once inside the vascular tissue, C. pneumoniae infection has been shown to induce the production of reactive oxygen species in all the cells involved in atherosclerotic process such as macrophages, platelets, endothelial cells, and vascular smooth muscle cells, leading to oxidative stress. The aim of this review is to summarize the data linking C. pneumoniae-induced oxidative stress to atherosclerotic lesion development.

  5. Cost-effectiveness of Chlamydia Vaccination Programs for Young Women

    Centers for Disease Control (CDC) Podcasts

    2015-06-19

    Dr. Kwame Owusu-Edusei discusses the importance of chlamydia vaccine development.  Created: 6/19/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/22/2015.

  6. Screening for Chlamydia trachomatis in Low-Risk Obstetric Patients

    Directory of Open Access Journals (Sweden)

    Robert K. Gribble

    1994-01-01

    Full Text Available Objective: The purpose of this study was to evaluate the prevalence of Chlamydia trachomatis in our rural obstetric population and assess the appropriateness of selective vs. universal prenatal screening.

  7. Study on Drug Resistance and Relative Mechanisms of Chlamydia Trachomatis

    Institute of Scientific and Technical Information of China (English)

    侯淑萍; 刘全忠

    2004-01-01

    Abstract: Chlamydia Trachomatis (C.T.) is one of the most common pathogens of human sexually transmitted diseases. Treatment of C.T. infection primarily depends on Tetracyclines, Macrolides and Quinolones, but with the wide use of antibiotics an increasing number of drug-resistant Chlamydia trachomatis cases have been reported. This review summarizes the resistant conditions and the possible resistance mechanisms of C.T..

  8. Laboratory diagnosis of Chlamydia pneumoniae infections

    Science.gov (United States)

    Peeling, Rosanna W

    1995-01-01

    Chlamydia pneumoniae is an important cause of respiratory illness. There is a need for accurate and rapid laboratory diagnostic methods that will lead to improved patient care, appropriate use of antimicrobial therapy and a better understanding of the epidemiology of this emerging pathogen. Culture is highly specific but is technically demanding, expensive, has a long turnaround time and its sensitivity is highly dependent on transport conditions. Antigen detection tests such as enzyme immunoassay and direct fluorescent antibody assay, and molecular detection methods such as the polymerase chain reaction assay, may provide a rapid diagnosis without the requirement for stringent transport conditions. The results of these tests should be interpreted with caution until more thorough evaluation is available. Serology remains the method of choice. The limitations of different serological methods for the laboratory diagnosis of C pneumoniae are discussed. PMID:22514397

  9. Laboratory Diagnosis of Chlamydia Pneumoniae Infections

    Directory of Open Access Journals (Sweden)

    Rosanna W Peeling

    1995-01-01

    Full Text Available Chlamydia pneumoniae is an important cause of respiratory illness. There is a need for accurate and rapid laboratory diagnostic methods that will lead to improved patient care, appropriate use of antimicrobial therapy and a better understanding of the epidemiology of this emerging pathogen. Culture is highly specific but is technically demanding, expensive, has a long turnaround time and its sensitivity is highly dependent on transport conditions. Antigen detection tests such as enzyme immunoassay and direct fluorescent antibody assay, and molecular detection methods such as the polymerase chain reaction assay, may provide a rapid diagnosis without the requirement for stringent transport conditions. The results of these tests should be interpreted with caution until more thorough evaluation is available. Serology remains the method of choice. The limitations of different serological methods for the laboratory diagnosis of C pneumoniae are discussed.

  10. Role of Chlamydia in Multiple Sclerosis.

    Science.gov (United States)

    Ivanova, M V; Kolkova, N I; Morgunova, E Yu; Pashko, Yu P; Zigangirova, N A; Zakharova, M N

    2015-09-01

    Chlamydia and antibodies to them were detected by serological, molecular biological, and culture methods in the sera and cerebrospinal fluid of patients with multiple sclerosis and in the reference groups of subjects without neurological diseases. Correlations between the agent presence in the biological fluids of patients and clinical characteristics of the disease were analyzed. C. pneumoniae were more incident in the biological liquids of patients with multiple sclerosis than in healthy volunteers. On the other hand, the incidence of the agent in the patients was not high and its presence did not correlate with the clinical manifestations. C. trachomatis was equally rare in the patients and volunteers. The studies indicated the existence of a group of patients infected by C. pneumoniae in the cohort of patients with multiple sclerosis, but the impact of this agent for the disease course remains unclear.

  11. Chlamydia pneumoniae and Atherosclerosis: The End?

    Directory of Open Access Journals (Sweden)

    LE Nicolle

    2005-01-01

    Full Text Available In this issue of the Journal, Patrick et al (pages 298-300 report on the results of a pilot study testing the hypothesis that seropositivity to Chlamydia pneumoniae together with a specific bacteriophage protein is associated with first-episode myocardial infarction or unstable angina. The study evolved from an earlier report suggesting that C pneumoniae with phage seropositivity was strongly associated with the presence of abdominal aortic aneurysm. The phage association suggested a potential explanation for some of the variability in previous studies exploring C pneumoniae as a cause for atherosclerosis (ie, only selected strains of C pneumoniae were pathogenic. Patrick et al found no significant association or trend, and the authors concluded that the negative findings in their pilot study did not support further studies to address this potential association.

  12. The humoral immune response to Chlamydia trachomatis in patients with acute reactive arthritis

    DEFF Research Database (Denmark)

    Larsen, B; Birkelund, Svend; Mordhorst, CH;

    1994-01-01

    Sera from 25 patients with clinical signs of reactive arthritis were analysed for antibodies against Chlamydia trachomatis by immunoblotting. Purified elementary bodies, purified Chlamydia outer membrane complexes, and purified recombinant subcomponents were used as antigens. Antibodies against C...

  13. STD studies show spermicides protect against Chlamydia.

    Science.gov (United States)

    1986-01-01

    Evidence which suggests that spermicides provide protection against sexually transmitted diseases (STDs) is accumulating. Laboratory tests have repeatedly demonstrated that spermicides are capable of killing the bacteria responsible for several types of STDs, as well as the virus responsible for acquired immunodeficiency syndrome. Recently, studies conducted in Bangkok, Thailand and in New York City suggest that these protective effects are not confined to the laboratory but that they also occur among women who use spermicides in the real world. In the New York City study, Family Health International (FHI), using data collected by Planned Parenthood of New York City, compared STD prevalence rates for women using different contraceptive methods. Women who used spermicides, in comparison with women who used oral contraceptives (OCs), were 20% less likely to have contracted a STD, 30% less likely to have gonorrhea, and 60% less likely to have chlamydia. In the Thai study, conducted jointly by the FHI and the Ministry of Health, women at high risk of STDs were allocated either to a group which was instructed to use a vaginal sponge impregnated with nonoxynol-9 during intercourse or to a control group which received no vaginal contraceptives. All the women were either sterilized or using OCs, IUDs, or injectable contraceptives. Preliminary results suggest that the women who used the vaginal sponges were significantly less likely to contract chlamydia than the control group. In regard to the incidence of gonorrhea, no differences between the 2 groups was detected. In the Thai study methodological problems forced the researchers to redesign the study. In accordance with the new design, the women in the 2 groups will be crossed over after 6 weeks. This will allow the researchers to examine the effect of using or not using a vaginal spermicide on specific individuals. The findings of the 2 studies have special relevance given the increasing prevalence of STDs in many

  14. Hydrodynamic regulation of monocyte inflammatory response to an intracellular pathogen.

    Directory of Open Access Journals (Sweden)

    Shankar J Evani

    Full Text Available Systemic bacterial infections elicit inflammatory response that promotes acute or chronic complications such as sepsis, arthritis or atherosclerosis. Of interest, cells in circulation experience hydrodynamic shear forces, which have been shown to be a potent regulator of cellular function in the vasculature and play an important role in maintaining tissue homeostasis. In this study, we have examined the effect of shear forces due to blood flow in modulating the inflammatory response of cells to infection. Using an in vitro model, we analyzed the effects of physiological levels of shear stress on the inflammatory response of monocytes infected with chlamydia, an intracellular pathogen which causes bronchitis and is implicated in the development of atherosclerosis. We found that chlamydial infection alters the morphology of monocytes and trigger the release of pro-inflammatory cytokines TNF-α, IL-8, IL-1β and IL-6. We also found that the exposure of chlamydia-infected monocytes to short durations of arterial shear stress significantly enhances the secretion of cytokines in a time-dependent manner and the expression of surface adhesion molecule ICAM-1. As a functional consequence, infection and shear stress increased monocyte adhesion to endothelial cells under flow and in the activation and aggregation of platelets. Overall, our study demonstrates that shear stress enhances the inflammatory response of monocytes to infection, suggesting that mechanical forces may contribute to disease pathophysiology. These results provide a novel perspective on our understanding of systemic infection and inflammation.

  15. Exploring Chlamydia Positivity among Females on College Campuses, 2008-2010

    Science.gov (United States)

    Habel, Melissa A.; Leichliter, Jami S.; Torrone, Elizabeth

    2016-01-01

    Objective: Describe chlamydia positivity among young women tested at college health centers by student characteristics: age, race/ethnicity, and institution type. Participants: During 2008-2010, colleges participating in a national infertility prevention program provided chlamydia testing data from females aged 18-24. Methods: Chlamydia positivity…

  16. Chlamydia Trachomatis détourne l'énergie stockée de l'hôte et accumule le glycogène dans le lumen de l'inclusion par un chemin double

    OpenAIRE

    2015-01-01

    The human pathogen Chlamydia trachomatis is an obligate intracellular bacterium, which develops in a parasitophorous compartment called inclusion. The inclusion membrane serves as a barrier to host defense mechanisms, but limits access to nutrients. One essential nutrient for C. trachomatis is glucose, and its polymer, glycogen, is highly abundant in the inclusion lumen. This work aimed to reconstitute the glucose flow in C. trachomatis infected cells and to understand the mechanisms for glyc...

  17. Intracellular drug release nanosystems

    Directory of Open Access Journals (Sweden)

    Fenghua Meng

    2012-10-01

    Full Text Available In order to elicit therapeutic effects, many drugs including small molecule anticancer drugs, proteins, siRNA, and DNA have to be delivered and released into the specific cellular compartments typically the cytoplasm or nucleus of target cells. Intracellular environment-responsive nanosystems that exhibit good extracellular stability while rapidly releasing drugs inside cancer cells have been actively pursued for effective cancer therapy. Here, we highlight novel designs of smart nanosystems that release drugs in response to an intracellular biological signal of cancer cells such as acidic pH in endo/lysosomal compartments, enzymes in lysosomes, and redox potential in cytoplasm and the cell nucleus.

  18. Quinolone-resistance in Salmonella is associated with decreased mRNA expression of virulence genes invA and avrA, growth and intracellular invasion and survival.

    Science.gov (United States)

    Wang, Yu-Ping; Li, Lin; Shen, Jian-Zhong; Yang, Fu-Jiang; Wu, Yong-Ning

    2009-02-01

    A variety of environmental factors, such as oxygen, pH, osmolarity and antimicrobial agents, modulate the expression of Salmonella pathogenicity islands (SPI) genes. This study investigated SPI-1 gene expression and the pathogenicity of quinolone-resistant Salmonella. mRNA expression levels of the invA and avrA genes, located in SPI-1, in quinolone-susceptible and quinolone-resistant Salmonella strains were determined using real-time fluorescent quantitative reverse transcription-polymerase chain reaction (RT-PCR). Twenty-five quinolone-resistant Salmonella mutants were derived from quinolone-susceptible strains by multiple-passage selection through increasing concentrations of ciprofloxacin in vitro, while an additional 15 strains were quinolone-resistant Salmonella clinical isolates. Sequence analysis showed no gene deletion or point mutations of nine SPI-1 genes (including invA and avrA) occurred in either the selected or clinical quinolone-resistant strains, while a single gyrA point mutation (S83F) was observed in all 40 quinolone-resistant strains. The mRNA expression levels of invA and avrA were significantly decreased (P<0.005) in quinolone-resistant strains (clinically acquired or experimentally selected in vitro), compared to the quinolone-susceptible strains. The resistant strains also had a slower growth rate combined with decreased epithelial cell invasion and intracellular replication in epithelial cells and macrophages. The results suggest that quinolone-resistance may be associated with lower virulence and pathogenicity than in quinolone-susceptible strains.

  19. "Candidatus Mesochlamydia elodeae" (Chlamydiae: Parachlamydiaceae), a novel chlamydia parasite of free-living amoebae.

    Science.gov (United States)

    Corsaro, Daniele; Müller, Karl-Dieter; Wingender, Jost; Michel, Rolf

    2013-02-01

    Vannella sp. isolated from waterweed Elodea sp. was found infected by a chlamydia-like organism. This organism behaves like a parasite, causing the death through burst of its host. Once the vannellae degenerated, the parasite was successfully kept in laboratory within a Saccamoeba sp. isolated from the same waterweed sample, which revealed in fine through electron microscopy to harbor two bacterial endosymbionts: the chlamydial parasite we introduce and another endosymbiont initially and naturally present in the host. Herein, we provide molecular-based identification of both the amoeba host and its two endosymbionts, with special focus on the chlamydia parasite. High sequence similarity values of the 18S rDNA permitted to assign the amoeba to the species Saccamoeba lacustris (Amoebozoa, Tubulinea). The bacterial endosymbiont naturally harbored by the host belonged to Sphingomonas koreensis (Alpha-Proteobacteria). The chlamydial parasite showed a strict specificity for Saccamoeba spp., being unable to infect a variety of other amoebae, including Acanthamoeba, and it was itself infected by a bacteriophage. Sequence similarity values of the 16S rDNA and phylogenetic analysis indicated that this strain is a new member of the family Parachlamydiaceae, for which we propose the name "Candidatus Mesochlamydia elodeae."

  20. [Chlamydia: from population screening to individual repeated screening].

    Science.gov (United States)

    Bally, F; Quach, A

    2014-10-08

    Chlamydia trachomatis is a frequent sexually transmitted infection especially in young adults and adolescents. Its complications can impair a woman's reproductive potential. chlamydia control has several challenges. These include asymptomatic infections; a long duration of untreated infections; re-infections and partner treatments. Any person with infection is at high risk of re-infection. Repeated screening would decrease, at an individual level, the risk of complications. General practitioners, gynaecologists and centres for sexual health could participate in Chlamydia screening for asymptomatic infections, in Switzerland, the cost of the laboratory test is fixed by national tariff regulations. The cost is high and prohibitive for many, especially adolescents and young adults and needs to be lowered.

  1. Changes in chlamydia control activities in Europe between 2007 and 2012: A cross-national survey

    DEFF Research Database (Denmark)

    van den Broek, I; Andersen, Berit; Herrmann, B

    2015-01-01

    indicators of chlamydia prevention and control activities; countries were assigned to one of five categories of chlamydia control. Results: In 2012, more countries than in 2007 reported availability of national chlamydia case management guidelines (80% vs. 68%), opportunistic chlamydia testing (68% vs. 44......%) and consistent use of nucleic acid amplification tests (64% vs. 36%). The number of countries reporting having a national sexually transmitted infection control strategy or a surveillance system for chlamydia did not change notably. In 2012, most countries (18/25, 72%) had implemented primary prevention...... activities and case management guidelines addressing partner management, compared with 44% (11/25) of countries in 2007. Conclusion: Overall, chlamydia control activities in EU/EEA countries strengthened between 2007 and 2012. Several countries still need to develop essential chlamydia control activities...

  2. RNA interference screen identifies Abl kinase and PDGFR signaling in Chlamydia trachomatis entry.

    Directory of Open Access Journals (Sweden)

    Cherilyn A Elwell

    2008-03-01

    Full Text Available The strain designated Chlamydia trachomatis serovar L2 that was used for experiments in this paper is Chlamydia muridarum, a species closely related to C. trachomatis (and formerly termed the Mouse Pneumonitis strain of C. trachomatis. This conclusion was verified by deep sequencing and by PCR using species-specific primers. All data presented in the results section that refer to C. trachomatis should be interpreted as referring to C. muridarum. Since C. muridarum TARP lacks the consensus tyrosine repeats present in C. trachomatis TARP, we cannot make any conclusions about the role of TARP phosphorylation and C. muridarum entry. However, the conclusion that C. trachomatis L2 TARP is a target of Abl kinase is still valid as these experiments were performed with C. trachomatis L2 TARP [corrected]. To elucidate the mechanisms involved in early events in Chlamydia trachomatis infection, we conducted a large scale unbiased RNA interference screen in Drosophila melanogaster S2 cells. This allowed identification of candidate host factors in a simple non-redundant, genetically tractable system. From a library of 7,216 double stranded RNAs (dsRNA, we identified approximately 226 host genes, including two tyrosine kinases, Abelson (Abl kinase and PDGF- and VEGF-receptor related (Pvr, a homolog of the Platelet-derived growth factor receptor (PDGFR. We further examined the role of these two kinases in C. trachomatis binding and internalization into mammalian cells. Both kinases are phosphorylated upon infection and recruited to the site of bacterial attachment, but their roles in the infectious process are distinct. We provide evidence that PDGFRbeta may function as a receptor, as inhibition of PDGFRbeta by RNA interference or by PDGFRbeta neutralizing antibodies significantly reduces bacterial binding, whereas depletion of Abl kinase has no effect on binding. Bacterial internalization can occur through activation of PDGFRbeta or through independent

  3. Role of Chlamydia trachomatis in miscarriage.

    Science.gov (United States)

    Baud, David; Goy, Genevieve; Jaton, Katia; Osterheld, Maria-Chiara; Blumer, Serafin; Borel, Nicole; Vial, Yvan; Hohlfeld, Patrick; Pospischil, Andreas; Greub, Gilbert

    2011-09-01

    To determine the role of Chlamydia trachomatis in miscarriage, we prospectively collected serum, cervicovaginal swab specimens, and placental samples from 386 women with and without miscarriage. Prevalence of immunoglobulin G against C. trachomatis was higher in the miscarriage group than in the control group (15.2% vs. 7.3%; p = 0.018). Association between C. trachomatis-positive serologic results and miscarriage remained significant after adjustment for age, origin, education, and number of sex partners (odds ratio 2.3, 95% confidence interval 1.1-4.9). C. trachomatis DNA was more frequently amplified from products of conception or placenta from women who had a miscarriage (4%) than from controls (0.7%; p = 0.026). Immunohistochemical analysis confirmed C. trachomatis in placenta from 5 of 7 patients with positive PCR results, whereas results of immunohistochemical analysis were negative in placenta samples from all 8 negative controls tested. Associations between miscarriage and serologic/molecular evidence of C. trachomatis infection support its role in miscarriage.

  4. Tetracycline Susceptibility in Chlamydia suis Pig Isolates.

    Directory of Open Access Journals (Sweden)

    Manuela Donati

    Full Text Available The aims of the present study were to assess the prevalence of Chlamydia suis in an Italian pig herd, determine the tetracycline susceptibility of C. suis isolates, and evaluate tet(C and tetR(C gene expression. Conjunctival swabs from 20 pigs were tested for C. suis by real-time polymerase chain reaction, and 55% (11 were positive. C. suis was then isolated from 11 conjunctival swabs resampled from the same herd. All positive samples and isolates were positive for the tet(C resistance gene. The in vitro susceptibility to tetracycline of the C. suis isolates showed MIC values ranging from 0.5 to 4 μg/mL. Tet(C and tetR(C transcripts were found in all the isolates, cultured both in the absence and presence of tetracycline. This contrasts with other Gram-negative bacteria in which both genes are repressed in the absence of the drug. Further investigation into tet gene regulation in C. suis is needed.

  5. [Chlamydia trachomatis genital infections and contraception].

    Science.gov (United States)

    Aloisio, T; Rullo, F; Smeraglia, R; Giorgio, A; Lettieri, G; Sannino, F; Martinelli, A

    1988-01-01

    330 women with a median age of 30.15 (+- 9.5) years sought gynecological consultation for advice on contraception and for cervical carcinoma screening. Anamnesis explored the presence of dysuria, dyspareunia, secretions, and pelvic pain, the number of partners, and type of contraceptive used. Endocervical samples were collected by means of tampon and the specimens were analyzed for 48 to 120 hours to find antigens of Chlamydia trachomatis (C.T.) by a solid phase immunoenzymatic test. Peripheral blood samples were also taken from all women to look for antibodies of C.T. and also the indirect immunoperoxidase test was used to search for specific antibodies of C.T. (IgM, IgA, IgE, IgG). The chi-square test was applied for statistical analysis. None of the women who used oral hormonal contraceptives or condoms were infected (presence of antigens and positivity for IgM and/or IgE and/or IgA), however, 36 of 90 IUD users (40%) were infected, 18 of 132 women who used no contraceptives whatsoever (13.7%) were also infected. 91% of the subjects had a single partner. In view of these findings the use of the condom and oral contraceptives is recommended with proper instruction about their potential side effects.

  6. Tetracycline Susceptibility in Chlamydia suis Pig Isolates.

    Science.gov (United States)

    Donati, Manuela; Balboni, Andrea; Laroucau, Karine; Aaziz, Rachid; Vorimore, Fabien; Borel, Nicole; Morandi, Federico; Vecchio Nepita, Edoardo; Di Francesco, Antonietta

    2016-01-01

    The aims of the present study were to assess the prevalence of Chlamydia suis in an Italian pig herd, determine the tetracycline susceptibility of C. suis isolates, and evaluate tet(C) and tetR(C) gene expression. Conjunctival swabs from 20 pigs were tested for C. suis by real-time polymerase chain reaction, and 55% (11) were positive. C. suis was then isolated from 11 conjunctival swabs resampled from the same herd. All positive samples and isolates were positive for the tet(C) resistance gene. The in vitro susceptibility to tetracycline of the C. suis isolates showed MIC values ranging from 0.5 to 4 μg/mL. Tet(C) and tetR(C) transcripts were found in all the isolates, cultured both in the absence and presence of tetracycline. This contrasts with other Gram-negative bacteria in which both genes are repressed in the absence of the drug. Further investigation into tet gene regulation in C. suis is needed.

  7. Contemporary approaches to designing and evaluating vaccines against Chlamydia.

    Science.gov (United States)

    Igietseme, Joseph U; Eko, Francis O; Black, Carolyn M

    2003-02-01

    The clinically relevant pathologic consequences of primary ocular, genital, or respiratory human infection by members of the genus Chlamydia are conjunctivitis, cervicitis, urethritis and sinusitis. The major complications and sometimes debilitating evolutionary outcomes of these infections include: trichiasis and cicatrizing trachoma, endometritis or pelvic inflammatory disease and involuntary tubal factor infertility and bronchopulmonary pneumonia. These diseases, in addition to other chlamydia-associated chronic syndromes (e.g., artherosclerosis, multiple sclerosis and Alzheimer's disease), pose serious public healthcare and huge budgetary concerns. The current medical opinion is that an efficacious prophylactic vaccine is a sine qua non--to control the morbidity of chiamydial infection in the human population. The research goal for an efficacious human chlamydial vaccine has faced key challenges to define the elements of protective immunity to facilitate vaccine evaluation, the judicious selection of appropriate vaccine candidates that possess stable antigenic and immunologic properties and the development of effective delivery vehicles and adjuvants to boost immune effectors to achieve long-term protective immunity. Progress in the functional immunobiology of Chlamydia has established the essential immunologic paradigms for vaccine selection and evaluation, including the obligatory requirement for a vaccine to induce T-helper Type 1 immune response that controls chlamydiae. Recent advances in chlamydial genomics and proteomics should enhance the identification of likely chlamydial gene products that fulfill the antigenic requirements of putative vaccine candidates. Major inroads are however needed in the construction and development of novel and effective delivery systems, such as vectors and adjuvants. This review summarizes the status of contemporary chlamydial vaccine research and promising trends fueling the growing optimism for an efficacious vaccine. The

  8. Gene Deletion by Fluorescence-Reported Allelic Exchange Mutagenesis in Chlamydia trachomatis

    Directory of Open Access Journals (Sweden)

    Konrad E. Mueller

    2016-01-01

    Full Text Available Although progress in Chlamydia genetics has been rapid, genomic modification has previously been limited to point mutations and group II intron insertions which truncate protein products. The bacterium has thus far been intractable to gene deletion or more-complex genomic integrations such as allelic exchange. Herein, we present a novel suicide vector dependent on inducible expression of a chlamydial gene that renders Chlamydia trachomatis fully genetically tractable and permits rapid reverse genetics by fluorescence-reported allelic exchange mutagenesis (FRAEM. We describe the first available system of targeting chlamydial genes for deletion or allelic exchange as well as curing plasmids from C. trachomatis serovar L2. Furthermore, this approach permits the monitoring of mutagenesis by fluorescence microscopy without disturbing bacterial growth, a significant asset when manipulating obligate intracellular organisms. As proof of principle, trpA was successfully deleted and replaced with a sequence encoding both green fluorescent protein (GFP and β-lactamase. The trpA-deficient strain was unable to grow in indole-containing medium, and this phenotype was reversed by complementation with trpA expressed in trans. To assess reproducibility at alternate sites, FRAEM was repeated for genes encoding type III secretion effectors CTL0063, CTL0064, and CTL0065. In all four cases, stable mutants were recovered one passage after the observation of transformants, and allelic exchange was limited to the specific target gene, as confirmed by whole-genome sequencing. Deleted sequences were not detected by quantitative real-time PCR (qPCR from isogenic mutant populations. We demonstrate that utilization of the chlamydial suicide vector with FRAEM renders C. trachomatis highly amenable to versatile and efficient genetic manipulation.

  9. Association of caveolin with Chlamydia trachomatis inclusions at early and late stages of infection.

    Science.gov (United States)

    Norkin, L C; Wolfrom, S A; Stuart, E S

    2001-06-10

    The mechanism by which the intracellular bacterial pathogen Chlamydia trachomatis enters eukaryotic cells is poorly understood. There are conflicting reports of entry occurring by clathrin-dependent and clathrin-independent processes. We report here that C. trachomatis serovar K enters HEp-2 and HeLa 229 epithelial cells and J-774A.1 mouse macrophage/monocyte cells via caveolin-containing sphingolipid and cholesterol-enriched raft microdomains in the host cell plasma membranes. First, filipin and nystatin, drugs that specifically disrupt raft function by cholesterol chelation, each impaired entry of C. trachomatis serovar K. In control experiments, filipin did not impair entry of the same organism by an antibody-mediated opsonic process, nor did it impair entry of BSA-coated microspheres. Second, the chlamydia-containing endocytic vesicles specifically reacted with antisera against the caveolae marker protein caveolin. These vesicles are known to become the inclusions in which parasite replication occurs. They avoid fusion with lysosomes and instead traffic to the Golgi region, where they intercept Golgi-derived vesicles that recycle sphingolipids and cholesterol to the plasma membrane. We also report that late-stage C. trachomatis inclusions continue to display high levels of caveolin, which they likely acquire from the exocytic Golgi vesicles. We suggest that the atypical raft-mediated entry process may have important consequences for the host-pathogen interaction well after entry has occurred. These consequences include enabling the chlamydial vesicle to avoid acidification and fusion with lysosomes, to traffic to the Golgi region, and to intercept sphingolipid-containing vesicles from the Golgi.

  10. The novel chlamydial adhesin CPn0473 mediates the lipid raft-dependent uptake of Chlamydia pneumoniae.

    Science.gov (United States)

    Fechtner, Tim; Galle, Jan N; Hegemann, Johannes H

    2016-08-01

    Chlamydiae are Gram-negative, obligate intracellular pathogens that pose a serious threat to public health worldwide. Chlamydial surface molecules are essential for host cell invasion. The first interaction with the host cell is thereby accomplished by the Outer membrane complex protein B (OmcB) binding to heparan sulfate moieties on the host cell surface, followed by the interaction of the chlamydial polymorphic membrane proteins (Pmps) with host cell receptors. Specifically, the interaction of the Pmp21 adhesin and invasin with its human interaction partner, the epidermal growth factor receptor, results in receptor activation, down-stream signalling and finally internalization of the bacteria. Blocking both, the OmcB and Pmp21 adhesion pathways, did not completely abolish infection, suggesting the presence of additional factors relevant for host cell invasion. Here, we show that the novel surface protein CPn0473 of Chlamydia pneumoniae contributes to the binding and invasion of infectious chlamydial particles. CPn0473 is expressed late in the infection cycle and located on the infectious chlamydial cell surface. Soluble recombinant CPn0473 as well as rCPn0473-coupled fluorescent latex beads adhere to human epithelial HEp-2 cells. Interestingly, in classical infection blocking experiments pretreatment of HEp-2 cells with rCPn0473 does not attenuate adhesion but promotes dose-dependently internalization by C. pneumoniae suggesting an unusual mode of action for this adhesin. This CPn0473-dependent promotion of infection by C. pneumoniae depends on two different domains within the protein and requires intact lipid rafts. Thus, inhibition of the interaction of CPn0473 with the host cell could provide a way to reduce the virulence of C. pneumoniae.

  11. The novel chlamydial adhesin CPn0473 mediates the lipid raft‐dependent uptake of Chlamydia pneumoniae

    Science.gov (United States)

    Fechtner, Tim; Galle, Jan N.

    2016-01-01

    Summary Chlamydiae are Gram‐negative, obligate intracellular pathogens that pose a serious threat to public health worldwide. Chlamydial surface molecules are essential for host cell invasion. The first interaction with the host cell is thereby accomplished by the Outer membrane complex protein B (OmcB) binding to heparan sulfate moieties on the host cell surface, followed by the interaction of the chlamydial polymorphic membrane proteins (Pmps) with host cell receptors. Specifically, the interaction of the Pmp21 adhesin and invasin with its human interaction partner, the epidermal growth factor receptor, results in receptor activation, down‐stream signalling and finally internalization of the bacteria. Blocking both, the OmcB and Pmp21 adhesion pathways, did not completely abolish infection, suggesting the presence of additional factors relevant for host cell invasion. Here, we show that the novel surface protein CPn0473 of Chlamydia pneumoniae contributes to the binding and invasion of infectious chlamydial particles. CPn0473 is expressed late in the infection cycle and located on the infectious chlamydial cell surface. Soluble recombinant CPn0473 as well as rCPn0473‐coupled fluorescent latex beads adhere to human epithelial HEp‐2 cells. Interestingly, in classical infection blocking experiments pretreatment of HEp‐2 cells with rCPn0473 does not attenuate adhesion but promotes dose‐dependently internalization by C. pneumoniae suggesting an unusual mode of action for this adhesin. This CPn0473‐dependent promotion of infection by C. pneumoniae depends on two different domains within the protein and requires intact lipid rafts. Thus, inhibition of the interaction of CPn0473 with the host cell could provide a way to reduce the virulence of C. pneumoniae. PMID:26780295

  12. Is there a Relation between Chlamydia Infection and Primary Biliary Cirrhosis?

    Science.gov (United States)

    Leung, Patrick S. C.; Park, Ogyi; Matsumura, Shuji; Ansari, Aftab A.; Coppel, Ross L.; Gershwin, M. Eric

    2003-01-01

    Over the past two decades, a number of studies have failed to provide direct evidence of specific microbial chronic infection in primary biliary cirrhosis (PBC). However, a recent report suggests that there is a specific association of Chlamydia pneumoniae in patients with PBC and that C. pneumoniae or similar antigens might play a role in the pathogenesis of disease. To determine if Chlamydia infection is associated with PBC, we applied a combination of immunological and molecular approaches to investigate (a) the serological reactivity against two common Chlamydia human pathogens, C. pneumoniae and C. trachomatis, by immunoblotting, (b) the presence of Chlamydia in liver samples of patients with PBC and controls by PCR amplification of Chlamydia specific 16S rRNA and (c) the presence of Chlamydia proteins in liver samples of patients with PBC and controls by immunohistochemical staining. By immunoblotting, C. trachomatis and C. pneumoniae specific serological antibodies were found in 52/57 (91.2%) AMA positive PBC, 7/33 (21/2%) of AMA negative PBC, 1/25 (4%) PSC, 0/15 (0%) Sjorgen's syndrome and 0/20 (0%) systemic lupus erythematosus patients and 0/20 (0%) healthy volunteers at 1:200 sera dilution. PBC sera reacted to Chlamydia and E. coli lysates in western blots up to a maximum of 10-4 dilution. However, PCR amplification of the Chlamydia specific 16S rRNA gene was negative in 25/25 PBC livers but positive in 1/4 PSC liver, 3/6 in other liver disease controls and 1/4 normal liver samples. While two commercially available specific monoclonal antibodies stained positive controls (Chlamydia infected HEp-2 cells) they failed to detect Chlamydia antigens in PBC livers. The detection of Chlamydia specific antibodies but not Chlamydia rRNA gene and Chlamydia antigens in PBC suggests that Chlamydia infection is not involved in PBC. PMID:14768955

  13. Damage/Danger Associated Molecular Patterns (DAMPs) Modulate Chlamydia pecorum and C. trachomatis Serovar E Inclusion Development In Vitro.

    Science.gov (United States)

    Leonard, Cory Ann; Schoborg, Robert V; Borel, Nicole

    2015-01-01

    Persistence, more recently termed the chlamydial stress response, is a viable but non-infectious state constituting a divergence from the characteristic chlamydial biphasic developmental cycle. Damage/danger associated molecular patterns (DAMPs) are normal intracellular components or metabolites that, when released from cells, signal cellular damage/lysis. Purine metabolite DAMPs, including extracellular ATP and adenosine, inhibit chlamydial development in a species-specific manner. Viral co-infection has been shown to reversibly abrogate Chlamydia inclusion development, suggesting persistence/chlamydial stress. Because viral infection can cause host cell DAMP release, we hypothesized DAMPs may influence chlamydial development. Therefore, we examined the effect of extracellular ATP, adenosine, and cyclic AMP exposure, at 0 and 14 hours post infection, on C. pecorum and C. trachomatis serovar E development. In the absence of de novo host protein synthesis, exposure to DAMPs immediately post or at 14 hours post infection reduced inclusion size; however, the effect was less robust upon 14 hours post infection exposure. Additionally, upon exposure to DAMPs immediately post infection, bacteria per inclusion and subsequent infectivity were reduced in both Chlamydia species. These effects were reversible, and C. pecorum exhibited more pronounced recovery from DAMP exposure. Aberrant bodies, typical in virus-induced chlamydial persistence, were absent upon DAMP exposure. In the presence of de novo host protein synthesis, exposure to DAMPs immediately post infection reduced inclusion size, but only variably modulated chlamydial infectivity. Because chlamydial infection and other infections may increase local DAMP concentrations, DAMPs may influence Chlamydia infection in vivo, particularly in the context of poly-microbial infections.

  14. Cost-effectiveness of Chlamydia Vaccination Programs for Young Women

    OpenAIRE

    Owusu-Edusei, Kwame; Harrell W Chesson; Gift, Thomas L.; Brunham, Robert C.; Bolan, Gail

    2015-01-01

    We explored potential cost-effectiveness of a chlamydia vaccine for young women in the United States by using a compartmental heterosexual transmission model. We tracked health outcomes (acute infections and sequelae measured in quality-adjusted life-years [QALYs]) and determined incremental cost-effectiveness ratios (ICERs) over a 50-year analytic horizon. We assessed vaccination of 14-year-old girls and catch-up vaccination for 15–24-year-old women in the context of an existing chlamydia sc...

  15. Infection of Human Retinal Pigment Epithelium with Chlamydia trachomatis.

    Directory of Open Access Journals (Sweden)

    Ernest Boiko

    Full Text Available Little is known about the susceptibility of posterior segment tissues, particularly the human retinal pigment epithelium (hRPE, to Chlamydia trachomatis. The purpose of the study was to investigate the possibility of infecting the hRPE with Chlamydia trachomatis, and to examine the infectivity of different Chlamydia trachomatis clinical isolates for hRPE cells and the hRPE cell response to the infection.Cultured hRPE and McCoy cells were inoculated with eight Chlamydia trachomatis (serovar E clinical isolates at multiplicity of infection (MOI of 2.0 or 0.3. To detect Chlamydia trachomatis, samples were stained immunohistochemically with anti-major outer membrane protein antibodies at 24h, 48h, and 72h postinoculation (PI. The changes in the expression of signaling molecules and proteins of cytoskeleton and extracellular matrix in hRPE cells were examined immunohistochemically.All eight clinical isolates demonstrated ability to infect hRPE cells. At equal MOI of 0.3, the infectivity of Chlamydia trachomatis clinical isolates for RPE culture was found to be at least as high as that for McCoy cell culture. At 24h PI, the percentage of inclusion-containing cells varied from 1.5 ± 0.52 to 14.6 ± 3.3% in hRPE cell culture infected at MOI of 2.0 against 0.37 ± 0.34 to 8.9 ± 0.2% in McCoy cell culture infected at MOI of 0.3. Collagen type I, collagen type IV, basic fibroblast growth factor, transforming growth factor-beta and interleukin-8 expression at 48h PI were maximally increased, by 2.1-, 1.3-, 1.5-, 1.5- and 1.6-fold, respectively, in the Chlamydia trachomatis-infected compared with control hRPE cell culture specimens (P < 0.05.This study, for the first time, proved the possibility of infecting hRPE cultured cells with Chlamydia trachomatis, which leads to proproliferative and proinflammatory changes in the expression of signaling molecules and extracellular matrix components.

  16. Seroepidemiological survey of Chlamydia in North West zone of Nigeria

    Institute of Scientific and Technical Information of China (English)

    Agbonlahor DE; Okoror LE; Esumeh FI

    2009-01-01

    Objective:Chlamydia is made of organism responsible for respiratory as well as genital infections with very se-rious sequelae.In Nigeria there is paucity of information regards relative frequencies of Chlamydia infection of which this study reports in North West zone of Nigeria.Methods:Three hundred and thirty three (333)blood samples were collected from individuals attending various clinics in North West zone of Nigeria and tested for Chlamydia complement fixing antibody.Swabs collected from positive patients were re-tested using the Ro-manowsky-Giemsa staining technique.Statistical analysis were carried out in epi-info epidemiological software package.Results:From the total of 333 samples collected and tested for Chlamydia complement fixing anti-body (CCFA)only 287 (86%)were positive.The culture showed that 215 (75%)were positive for Chlamydia trachomatis while only 135 (47%)were positive for Chlamydia pneumoniae.Seventy-one (71)fe-males had symptomatic infection while 31 males were symptomatic.Of the 104 individuals who were asympto-matic 67 were females while 92 were males.Of the 31 symptomatic males were 22 positive to Chlamydia pneu-moniae and the symptoms being that of respiratory syndrome while 9 had difficulty urinating.All the symptom-atic women had symptoms resembling that of the pelvic inflammatory disease (PID)and vaginal discharge. Age groups 31-35 had the highest positive samples while the extreme ages had the lowest number of positive in-dividuals and also the lowest number of samples.The number of samples as well as the positive results were validated using the epi-info statistical package version 3.4.1.There was no significant difference in the num-ber of samples from both males and females (χ2 =1.360,CI =99%).Conclusion:A high percentage of pos-itive result as validated by statistical analysis shows that Chlamydia infections are endemic in the population and efforts should be made to screen for the organism to avoid the "silent epidemics".

  17. Role of Chlamydia trachomatis and emerging Chlamydia-related bacteria in ectopic pregnancy in Vietnam.

    Science.gov (United States)

    Hornung, S; Thuong, B C; Gyger, J; Kebbi-Beghdadi, C; Vasilevsky, S; Greub, G; Baud, D

    2015-09-01

    In this case-control study, we investigated the seroprevalence and molecular evidence of Chlamydia trachomatis and Waddlia chondrophila in ectopic pregnancies (EP) and uneventful control pregnancies in 343 women from Vietnam. Whereas presence of C. trachomatis IgG was strongly associated with EP [adjusted odds ratio (aOR) 5·41, 95% confidence interval (CI) 2·58-11·32], its DNA remained undetected in all tubal lesions. We confirmed an independent association between antibodies against Waddlia and previous miscarriage (aOR 1·87, 95% CI 1·02-3·42). Further investigations are needed to understand the clinical significance of Waddlia's high seroprevalence (25·9% in control pregnancies) in this urban population.

  18. Chlamydia trachomatis Genotypes and the Swedish New Variant among Urogenital Chlamydia trachomatis Strains in Finland

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    Suvi Niemi

    2011-01-01

    Full Text Available Our aims were to genotype Chlamydia trachomatis strains present in urogenital samples and to investigate the occurrence of the Swedish new variant of C. trachomatis in Finland. We genotyped 160 C. trachomatis positive samples with ompA real-time PCR and analyzed 495 samples for the new variant. The three most prevalent genotypes were E (40%, F (28%, and G (13%. Only two specimens containing bacteria with the variant plasmid were detected. It seems that in Finland the percentage of infections due to genotypes F and G has slightly increased during the last 20 years. Genotypes E and G appear to be more common, and genotypes J/Ja and I/Ia appear to be less common in Europe than in the USA. Although the genotype E was the most common genotype among C. trachomatis strains, the new variant was rarely found in Finland.

  19. Chlamydia pecorum: fetal and placental lesions in sporadic caprine abortion.

    Science.gov (United States)

    Giannitti, Federico; Anderson, Mark; Miller, Myrna; Rowe, Joan; Sverlow, Karen; Vasquez, Marce; Cantón, Germán

    2016-03-01

    Chlamydial abortion in small ruminants is usually associated with Chlamydia abortus infection. Although Chlamydia pecorum has been detected in aborted ruminants and epidemiological data suggests that C. pecorum is abortigenic in these species, published descriptions of lesions in fetuses are lacking. This work describes fetoplacental lesions in a caprine abortion with C. pecorum infection, and further supports the abortigenic role of C. pecorum in ruminants. A 16-month-old Boer goat aborted twin fetuses at ~130 days of gestation. Both fetuses (A and B) and the placenta of fetus A were submitted for postmortem examination and diagnostic workup. At autopsy, the fetuses had moderate anasarca, intermuscular edema in the hindquarters (A), and brachygnathia and palatoschisis (B). In the placenta, the cotyledons were covered by yellow fibrinosuppurative exudate that extended into the adjacent intercotyledonary areas. Histologically, there was severe suppurative and necrotizing placentitis with vasculitis (arteriolitis) and thrombosis, multifocal lymphohistiocytic and neutrophilic hepatitis (A), and fibrinosuppurative enteritis in both fetuses. Chlamydia antigen was detected in the placenta by the direct fluorescent antibody test and in fetal intestines by immunohistochemistry. Nested polymerase chain reaction of DNA extracted from formalin-fixed, paraffin-embedded sections of placenta and intestine amplified 400 bp of the Chlamydia 16S rRNA gene that was sequenced and found to be 99% identical to C. pecorum by BLAST analysis. Other known abortigenic infectious agents were ruled out by specific testing. It is concluded that C. pecorum infection is associated with fetoplacental lesions and sporadic abortion in goats.

  20. Use of polymerase chain reaction for detection of Chlamydia trachomatis

    DEFF Research Database (Denmark)

    Østergaard, Lars; Birkelund, Svend; Christiansen, Gunna

    1990-01-01

    A polymerase chain reaction (PCR) assay was developed for detection of Chlamydia trachomatis DNA. From the published sequence of the common C. trachomatis plasmid, two primer sets were selected. Detection of amplified sequences was done by agarose gel electrophoresis of cleaved or uncleaved...

  1. Seroprevalence and genotype of Chlamydia in pet parrots in China.

    Science.gov (United States)

    Zhang, N-Z; Zhang, X-X; Zhou, D-H; Huang, S-Y; Tian, W-P; Yang, Y-C; Zhao, Q; Zhu, X-Q

    2015-01-01

    Parrots are one of the most popular pet birds in China, and can harbour Chlamydia which has significance for human and animal health. We investigated, by indirect haemagglutination assay, the seroprevalence of Chlamydia infection in four species of parrots, namely budgerigars (Melopsittacus undulatus), lovebirds (Agapornis sp.), cockatiels (Nymphicus hollandicus) and Alexandrine parakeets (Psittacula eupatria) that were collected from Weifang and Beijing cities, North China and explored the association between potential risk factors and chlamydial seropositivity. We further determined the genotype of Chlamydia in 21 fresh faecal samples based on the ompA sequence by reconstruction of phylogenetic relationships. Of the 311 parrots examined, 35·37% (95% confidence interval 30·06-40·68) were seropositive, and species, gender, age, season and geographical location were identified as risk factors. Two PCR-positive samples represented Chlamydia psittaci genotype A. The occurrence of C. psittaci genotype A in the droppings of two pet parrots in China suggests potential environmental contamination with Chlamydiaceae and may raise a public health concern.

  2. Molecular detection of Chlamydia trachomatis and Neisseria gonorrhoeae

    DEFF Research Database (Denmark)

    Møller, Jens Kjølseth; Herrmann, B; Jensen, K.T.;

    2011-01-01

    This chapter highlights the use of nucleic acid amplification tests (NAATs) for the molecular diagnosis of gonorrhoea and chlamydia infection. In addition, good laboratory practice and issues that should be considered before and after implementation of NAATs for C. trachomatis and N. gonorrhoeae...

  3. Absence of Chlamydia-like organisms in pigs

    Directory of Open Access Journals (Sweden)

    M. Van Gils

    2015-09-01

    Full Text Available Porcine reproductive failure, especially abortion, causes significant economic loss in the pig industry. Waddlia chondrophila and Parachlamydia acanthamoebae are potential abortigenic agents for pigs. Therefore, we investigated the presence of these two Chlamydia-like organisms in abortion-related samples originating from Belgian pig farms. All investigated samples remained negative.

  4. Chlamydia trachomatis infection and risk of cervical intraepithelial neoplasia

    DEFF Research Database (Denmark)

    Lehtinen, Matti; Ault, Kevin A; Lyytikainen, Erika

    2011-01-01

    High-risk human papillomavirus (hrHPV) is the primary cause of cervical cancer. As Chlamydia trachomatis is also linked to cervical cancer, its role as a potential co-factor in the development of cervical intraepithelial neoplasia (CIN) grade 2 or higher was examined....

  5. A mouse model for Chlamydia suis genital infection.

    Science.gov (United States)

    Donati, Manuela; Di Paolo, Maria; Favaroni, Alison; Aldini, Rita; Di Francesco, Antonietta; Ostanello, Fabio; Biondi, Roberta; Cremonini, Eleonora; Ginocchietti, Laura; Cevenini, Roberto

    2015-02-01

    A mouse model for Chlamydia suis genital infection was developed. Ninety-nine mice were randomly divided into three groups and intravaginally inoculated with chlamydia: 45 mice (group 1) received C. suis purified elementary bodies (EBs), 27 (group 2) were inoculated with C. trachomatis genotype E EBs and 27 mice (group 3) with C. trachomatis genotype F EBs. Additionally, 10 mice were used as a negative control. At seven days post-infection (dpi) secretory anti-C. suis IgA were recovered from vaginal swabs of all C. suis inoculated mice. Chlamydia suis was isolated from 93, 84, 71 and 33% vaginal swabs at 3, 5, 7 and 12 dpi. Chlamydia trachomatis genotype E and F were isolated from 100% vaginal swabs up to 7 dpi and from 61 and 72%, respectively, at 12 dpi. Viable C. suis and C. trachomatis organisms were isolated from uterus and tubes up to 16 and 28 dpi, respectively. The results of the present study show the susceptibility of mice to intravaginal inoculation with C. suis. A more rapid course and resolution of C. suis infection, in comparison to C. trachomatis, was highlighted. The mouse model could be useful for comparative investigations involving C. suis and C. trachomatis species.

  6. Chlamydia Pneumoniae Infections and Sudden Unexpected Deaths in Denmark.

    Science.gov (United States)

    Johannsen, Finn

    1993-01-01

    Blood samples from 38 runners on the Danish national orienteering team revealed no ongoing chlamydia pneumoniae, although 42% had an earlier infection, similar to the incidence in the general population. However, over 2% had an ongoing lyme borreliosis infection, and 18% had an earlier infection, which is a higher incidence than in the general…

  7. Human neutrophils dump Candida glabrata after intracellular killing.

    Science.gov (United States)

    Essig, Fabian; Hünniger, Kerstin; Dietrich, Stefanie; Figge, Marc Thilo; Kurzai, Oliver

    2015-11-01

    Interaction between fungal pathogens and human phagocytes can lead to remarkably variable outcomes, ranging from intracellular killing to prolonged survival and replication of the pathogen in the host cell. Using live cell imaging we observed primary human neutrophils that release phagocytosed Candida glabrata yeast cells after intracellular killing. This process, for which we propose the name "dumping", adds a new outcome to phagocyte-fungus interaction which may be of potential immunological importance as it allows professional antigen presenting cells to take up and process neutrophil-inactivated pathogens that in their viable state are able to evade intracellular degradation in these cells.

  8. Does population screening for Chlamydia trachomatis raise anxiety among those tested? Findings from a population based chlamydia screening study

    Directory of Open Access Journals (Sweden)

    Low Nicola

    2006-04-01

    Full Text Available Abstract Background The advent of urine testing for Chlamydia trachomatis has raised the possibility of large-scale screening for this sexually transmitted infection, which is now the most common in the United Kingdom. The purpose of this study was to investigate the effect of an invitation to be screened for chlamydia and of receiving a negative result on levels of anxiety, depression and self-esteem. Methods 19,773 men and women aged 16 to 39 years, selected at random from 27 general practices in two large city areas (Bristol and Birmingham were invited by post to send home-collected urine samples or vulvo-vaginal swabs for chlamydia testing. Questionnaires enquiring about anxiety, depression and self-esteem were sent to random samples of those offered screening: one month before the dispatch of invitations; when participants returned samples; and after receiving a negative result. Results Home screening was associated with an overall reduction in anxiety scores. An invitation to participate did not increase anxiety levels. Anxiety scores in men were lower after receiving the invitation than at baseline. Amongst women anxiety was reduced after receipt of negative test results. Neither depression nor self-esteem scores were affected by screening. Conclusion Postal screening for chlamydia does not appear to have a negative impact on overall psychological well-being and can lead to a decrease in anxiety levels among respondents. There is, however, a clear difference between men and women in when this reduction occurs.

  9. Genital chlamydia trachomatis infection among female undergraduate students of University of Port Harcourt, Nigeria

    Directory of Open Access Journals (Sweden)

    A Ugboma Henry Arinze

    2014-01-01

    Full Text Available Background: Genital Chlamydia trachomatis infection is a common bacterial sexually transmitted infection worldwide. There is little information about this infection in Nigeria. This study determined the prevalence of genital Chlamydia trachomatis infection among female undergraduates of University of Port Harcourt and identify the various associated risk factors. Materials and Methods: A cross-sectional prospective study of 354 female students was done. Their socio-demographic characteristics and pattern of sexual behaviour was noted followed by collection of endocervical swab which was analysed with a Chlamydia Rapid Test Device. Data management was done by SPSS version 17.0 statistical package. Result: The prevalence of genital Chlamydia trachomatis infection was 30.2%. First coital exposure at14 years or less had the highest prevalence of the disease. Multiple sexual partners, tribe and inconsistent use of condom were significantly related with Chlamydia trachomatis infection. Conclusion: Genital Chlamydia trachomatis is prevalent among female undergraduates of the University of Port Harcourt.

  10. Evolution of intracellular compartmentalization.

    Science.gov (United States)

    Diekmann, Yoan; Pereira-Leal, José B

    2013-01-15

    Cells compartmentalize their biochemical functions in a variety of ways, notably by creating physical barriers that separate a compartment via membranes or proteins. Eukaryotes have a wide diversity of membrane-based compartments, many that are lineage- or tissue-specific. In recent years, it has become increasingly evident that membrane-based compartmentalization of the cytosolic space is observed in multiple prokaryotic lineages, giving rise to several types of distinct prokaryotic organelles. Endosymbionts, previously believed to be a hallmark of eukaryotes, have been described in several bacteria. Protein-based compartments, frequent in bacteria, are also found in eukaryotes. In the present review, we focus on selected intracellular compartments from each of these three categories, membrane-based, endosymbiotic and protein-based, in both prokaryotes and eukaryotes. We review their diversity and the current theories and controversies regarding the evolutionary origins. Furthermore, we discuss the evolutionary processes acting on the genetic basis of intracellular compartments and how those differ across the domains of life. We conclude that the distinction between eukaryotes and prokaryotes no longer lies in the existence of a compartmentalized cell plan, but rather in its complexity.

  11. Chlamydia species in free-living Cattle Egret (Bubulcus ibis) and Hoopoe (Upupa epops) in Egypt

    OpenAIRE

    El-Jakee, Jakeen K.; Osman, Kamelia M; Nashwa A. Ezzeldeen; Hadia A. Ali; Eman R. Mostafa

    2014-01-01

    Little information is available on the presence of chlamydia infection in wildlife. This study was conducted to assess the occurrence of chlamydiae in asymptomatic birds from two species of wild birds (Cattle Egret and Hoopoe) in Egypt. In the present study Chlamydiaceae was analyzed using Giemsa stain, Giménez stain, fluorescent antibody test (FAT) and PCR. The results of these techniques were compared with CFT for detecting Chlamydia psittaci antibodies among the examined birds. The results...

  12. Influence of the tryptophan-indole-IFNγ axis on human genital Chlamydia trachomatis infection: role of vaginal co-infections

    Directory of Open Access Journals (Sweden)

    Ashok eAiyar

    2014-06-01

    Full Text Available The natural history of genital Chlamydia trachomatis infections can vary widely; infections can spontaneously resolve but can also last from months to years, potentially progressing to cause significant pathology. The host and bacterial factors underlying this wide variation are not completely understood, but emphasize the bacterium’s capacity to evade/adapt to the genital immune response, and/or exploit local environmental conditions to survive this immune response. IFNγ is considered to be a primary host protective cytokine against endocervical C. trachomatis infections. IFNγ acts by inducing the host enzyme indoleamine 2,3-dioxygenase, which catabolizes tryptophan, thereby depriving the bacterium of this essential amino acid. In vitro studies have revealed that tryptophan deprivation causes Chlamydia to enter a viable but non-infectious growth pattern that is termed a persistent growth form, characterized by a unique morphology and gene expression pattern. Provision of tryptophan can reactivate the bacterium to the normal developmental cycle. There is a significant difference in the capacity of ocular and genital C. trachomatis serovars to counter tryptophan deprivation. The latter uniquely encode a functional tryptophan synthase to synthesize tryptophan via indole salvage, should indole be available in the infection microenvironment. In vitro studies have confirmed the capacity of indole to mitigate the effects of IFNγ; it has been suggested that a perturbed vaginal microbiome may provide a source of indole in vivo. Consistent with this hypothesis, the microbiome associated with bacterial vaginosis includes species that encode a tryptophanase to produce indole. In this review, we discuss the natural history of genital chlamydial infections, morphological and molecular changes imposed by IFNγ on Chlamydia, and finally, the microenvironmental conditions associated with vaginal co-infections that can ameliorate the effects of IFNγ on C

  13. Chlamydia and sudden infant death syndrome. A study of 166 SIDS and 30 control cases

    DEFF Research Database (Denmark)

    Banner, Jytte; Lundemose, A G; Gregersen, M;

    1990-01-01

    Chlamydia inclusions could be demonstrated by an immunofluorescence assay in formalin-fixed lung sections in 32 of 166 cases (19.4%) of Sudden Infant Death Syndrome (SIDS) and in the lungs of only 1 of 30 infants with a known cause of death (3.3%). The difference is statistically significant (P = 0.......04). Chlamydia trachomatis is an agent of pneumonia in 1-4 month-old infants who have acquired the disease from an infected cervix during birth, but other chlamydia species are also capable of causing pneumonia. The lung sections of the 32 chlamydia positive SIDS cases did not show typical histological signs...

  14. Detection of Chlamydia trachomatis in asymptomatic women: relationship to history, contraception, and cervicitis.

    Science.gov (United States)

    Bontis, J; Vavilis, D; Panidis, D; Theodoridis, T; Konstantinidis, T; Sidiropoulou, A

    1994-12-01

    The presence of Chlamydia trachomatis antigen was examined in 400 endocervical samples collected from an equal number of asymptomatic sexually active women. The overall prevalence was found to be 4%, using the enzyme-linked immunosorbent assay. Chlamydia infection was correlated with younger age (5.8%, p 0.05), condom (0%, p Chlamydia trachomatis infection is associated with younger age, intense sexual life, and use of oral contraceptives. Given that the majority of infected women revealed cervical pathology, the detection of chlamydia in the high-risk female population with cervical changes seems to be essential.

  15. Knowledge and acceptability of Chlamydia trachomatis screening among pregnant women and their partners: a cross-sectional study.

    NARCIS (Netherlands)

    Pereboom, M.T.R.; Spelten, E.R.; Manniën, J.; Rours, G.I.J.G.; Morré, S.A.; Schellevis, F.G.; Hutton, E.K.

    2014-01-01

    Background: Chlamydia trachomatis infections in pregnancy can cause maternal disease, adverse pregnancy outcomes and neonatal disease, which is why chlamydia screening during pregnancy has been advocated. The effectiveness of a screening program depends on the knowledge of health care professionals,

  16. Inhibition of apoptosis in neuronal cells infected with Chlamydophila (Chlamydia pneumoniae

    Directory of Open Access Journals (Sweden)

    Albert Elizabeth V

    2008-01-01

    Full Text Available Abstract Background Chlamydophila (Chlamydia pneumoniae is an intracellular bacterium that has been identified within cells in areas of neuropathology found in Alzheimer disease (AD, including endothelia, glia, and neurons. Depending on the cell type of the host, infection by C. pneumoniae has been shown to influence apoptotic pathways in both pro- and anti-apoptotic fashions. We have hypothesized that persistent chlamydial infection of neurons may be an important mediator of the characteristic neuropathology observed in AD brains. Chronic and/or persistent infection of neuronal cells with C. pneumoniae in the AD brain may affect apoptosis in cells containing chlamydial inclusions. Results SK-N-MC neuroblastoma cells were infected with the respiratory strain of C. pneumoniae, AR39 at an MOI of 1. Following infection, the cells were either untreated or treated with staurosporine and then examined for apoptosis by labeling for nuclear fragmentation, caspase activity, and membrane inversion as indicated by annexin V staining. C. pneumoniae infection was maintained through 10 days post-infection. At 3 and 10 days post-infection, the infected cell cultures appeared to inhibit or were resistant to the apoptotic process when induced by staurosporine. This inhibition was demonstrated quantitatively by nuclear profile counts and caspase 3/7 activity measurements. Conclusion These data suggest that C. pneumoniae can sustain a chronic infection in neuronal cells by interfering with apoptosis, which may contribute to chronic inflammation in the AD brain.

  17. Chlamydia trachomatis Infection of Endocervical Epithelial Cells Enhances Early HIV Transmission Events.

    Science.gov (United States)

    Buckner, Lyndsey R; Amedee, Angela M; Albritton, Hannah L; Kozlowski, Pamela A; Lacour, Nedra; McGowin, Chris L; Schust, Danny J; Quayle, Alison J

    2016-01-01

    Chlamydia trachomatis causes a predominantly asymptomatic, but generally inflammatory, genital infection that is associated with an increased risk for HIV acquisition. Endocervical epithelial cells provide the major niche for this obligate intracellular bacterium in women, and the endocervix is also a tissue in which HIV transmission can occur. The mechanism by which CT infection enhances HIV susceptibility at this site, however, is not well understood. Utilizing the A2EN immortalized endocervical epithelial cell line grown on cell culture inserts, we evaluated the direct role that CT-infected epithelial cells play in facilitating HIV transmission events. We determined that CT infection significantly enhanced the apical-to-basolateral migration of cell-associated, but not cell-free, HIVBaL, a CCR5-tropic strain of virus, across the endocervical epithelial barrier. We also established that basolateral supernatants from CT-infected A2EN cells significantly enhanced HIV replication in peripheral mononuclear cells and a CCR5+ T cell line. These results suggest that CT infection of endocervical epithelial cells could facilitate both HIV crossing the mucosal barrier and subsequent infection or replication in underlying target cells. Our studies provide a mechanism by which this common STI could potentially promote the establishment of founder virus populations and the maintenance of local HIV reservoirs in the endocervix. Development of an HIV/STI co-infection model also provides a tool to further explore the role of other sexually transmitted infections in enhancing HIV acquisition.

  18. Chlamydia trachomatis CT771 (nudH) is an asymmetric Ap4A hydrolase

    Science.gov (United States)

    Barta, Michael L.; Lovell, Scott; Sinclair, Amy N.; Battaile, Kevin P.; Hefty, P. Scott

    2014-01-01

    Asymmetric diadenosine 5′,5′″-P1,P4-tetraphosphate (Ap4A) hydrolases are members of the Nudix superfamily that asymmetrically cleave the metabolite Ap4A into ATP and AMP while facilitating homeostasis. The obligate intracellular mammalian pathogen Chlamydia trachomatis possesses a single Nudix family protein, CT771. As pathogens that rely on a host for replication and dissemination typically have one or zero Nudix family proteins, this suggests that CT771 could be critical for chlamydial biology and pathogenesis. We identified orthologs to CT771 within environmental Chlamydiales that share active site residues suggesting a common function. Crystal structures of both apo- and ligand-bound CT771 were determined to 2.6 Å and 1.9 Å resolution, respectively. The structure of CT771 shows a αβα-sandwich motif with many conserved elements lining the putative Nudix active site. Numerous aspects of the ligand-bound CT771 structure mirror those observed in the ligand-bound structure of the Ap4A hydrolase from Caenorhabditis elegans. These structures represent only the second Ap4A hydrolase enzyme member determined from eubacteria and suggest that mammalian and bacterial Ap4A hydrolases might be more similar than previously thought. The aforementioned structural similarities, in tandem with molecular docking, guided the enzymatic characterization of CT771. Together, these studies provide the molecular details for substrate binding and specificity, supporting the analysis that CT771 is an Ap4A hydrolase (nudH). PMID:24354275

  19. Host preference and zoonotic potential of Chlamydia psittaci and C. gallinacea in poultry.

    Science.gov (United States)

    Hulin, Virginie; Oger, Sabrina; Vorimore, Fabien; Aaziz, Rachid; de Barbeyrac, Bertille; Berruchon, Jacques; Sachse, Konrad; Laroucau, Karine

    2015-02-01

    Chlamydia psittaci and C. gallinacea are obligate intracellular bacteria infecting poultry. We conducted a survey in two poultry slaughterhouses that were processing either exclusively ducks (A) or various poultry species except ducks (B). Cloacal swabs were collected from all incoming poultry flocks in the course of a week, and blood samples and pharyngeal swabs were taken from workers. Swabs were examined using PCR and sera were analyzed with two immunoassays. PCR testing revealed the presence of C. psittaci in 9/38 duck flocks and the complete absence of C. gallinacea in these flocks (slaughterhouse A), whereas 16/33 Chlamydiaceae-positive poultry flocks handled in slaughterhouse B harbored C. gallinacea only. In an episode of psittacosis in slaughterhouse A, where one PCR-positive worker presented clinical signs, seroconversions were detected in 10 workers. In contrast, serological responses of slaughterhouse B workers to C. psittaci were generally low. This is in line with the almost complete absence of C. psittaci in handled flocks, where in additional sampling campaigns the agent was detected only once in the course of a year. Our study indicates that C. psittaci has a certain preference for ducks, whereas C. gallinacea was the predominant chlamydial agent in chickens and guinea fowl flocks.

  20. IFN-gamma-inducible Irga6 mediates host resistance against Chlamydia trachomatis via autophagy.

    Directory of Open Access Journals (Sweden)

    Munir A Al-Zeer

    Full Text Available Chlamydial infection of the host cell induces Gamma interferon (IFNgamma, a central immunoprotector for humans and mice. The primary defense against Chlamydia infection in the mouse involves the IFNgamma-inducible family of IRG proteins; however, the precise mechanisms mediating the pathogen's elimination are unknown. In this study, we identify Irga6 as an important resistance factor against C. trachomatis, but not C. muridarum, infection in IFNgamma-stimulated mouse embryonic fibroblasts (MEFs. We show that Irga6, Irgd, Irgm2 and Irgm3 accumulate at bacterial inclusions in MEFs upon stimulation with IFNgamma, whereas Irgb6 colocalized in the presence or absence of the cytokine. This accumulation triggers a rerouting of bacterial inclusions to autophagosomes that subsequently fuse to lysosomes for elimination. Autophagy-deficient Atg5-/- MEFs and lysosomal acidification impaired cells surrender to infection. Irgm2, Irgm3 and Irgd still localize to inclusions in IFNgamma-induced Atg5-/- cells, but Irga6 localization is disrupted indicating its pivotal role in pathogen resistance. Irga6-deficient (Irga6-/- MEFs, in which chlamydial growth is enhanced, do not respond to IFNgamma even though Irgb6, Irgd, Irgm2 and Irgm3 still localize to inclusions. Taken together, we identify Irga6 as a necessary factor in conferring host resistance by remodelling a classically nonfusogenic intracellular pathogen to stimulate fusion with autophagosomes, thereby rerouting the intruder to the lysosomal compartment for destruction.

  1. Chlamydia trachomatis antigen in female genital tract infection

    Directory of Open Access Journals (Sweden)

    Badrinath S

    1996-01-01

    Full Text Available Thirty cases of female genital tract infection were investigated for the presence of Chlamydia trachomatis antigen. Endocervical swabs obtained were subjected to antigen detection by enzyme immunoassay. Rabbit antiserum to chlamydial lipopolysaccharide was used in a card test. Anti rabbit immunoglobulin G conjugated to alkaline phosphatase with a chromogenic substrate 5 bromo-4 chloro-3-indolyl phosphate and nitro blue tetrazolium were used for the enzymatic reaction. Chlamydial antigen could be detected in four out of thirty samples (13.3%. In contrast direct immunofluorescence detected 5 cases (16.6%. Although less sensitive, enzyme immunoassay can be used as a rapid diagnostic tool in detecting Chlamydia trachomatis antigen in genital infections.

  2. Female Reproductive Hormones and Biomarkers of Oxidative Stress in Genital Chlamydia Infection in Tubal Factor Infertility

    Science.gov (United States)

    Nsonwu-Anyanwu, Augusta Chinyere; Charles-Davies, Mabel Ayebantoyo; Taiwo, Victor Olusegun; Li, Bin; Oni, Anthony Alabar; Bello, Folashade Adenike

    2015-01-01

    Background Genital Chlamydia infection (GCI) and the associated pathologies have been implicated in tubal infertility. Though the actual pathologic mechanisms are still uncertain, oxidative stress and other factors have been implicated. The purpose of the study was to determine the possible contribution of female reproductive hormones and biomarkers of oxidative stress in genital Chlamydial infection to tubal occlusion. Methods This prospective case control study was carried out by recruiting 150 age matched women grouped into infertile Chlamydia positive women (n = 50), fertile Chlamydia positive women (n = 50) and fertile Chlamydia negative women as controls (n = 50). High vaginal swabs and endocervical swabs were collected for screening Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, Treponema pallidum, Staphylococcus aureus, and Candida albicans. Sera were collected for estimation of Chlamydia trachomatis antibody, female reproductive hormones [Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), Oestradiol (E2), Progesterone (P4), Prolactin (PRL)] and biomarkers of oxidative stress [Total Antioxidant Capacity (TAC) and 8-hydroxyl-2-deoxyguanosine (8-OHdG)] by enzyme immunoassay (EIA). Data were analyzed using chi square, analysis of variance and LSD Post hoc to determine mean differences at p = 0.05. Results Among women with GCI, higher levels of LH and 8-OHdG were observed in infertile Chlamydia positive women compared to fertile Chlamydia positive women (p < 0.05). Higher levels of LH and 8-OHdG and lower TAC levels were observed in infertile Chlamydia positive women compared to fertile Chlamydia negative controls (p < 0.05). Conclusion Mechanisms including oxidative DNA damage and reduced antioxidant capacity may be involved in the pathology of Chlamydia induced tubal damage. PMID:25927024

  3. The Type III Secretion System-Related CPn0809 from Chlamydia pneumoniae.

    Directory of Open Access Journals (Sweden)

    Astrid C Engel

    Full Text Available Chlamydia pneumoniae is an intracellular Gram-negative bacterium that possesses a type III secretion system (T3SS, which enables the pathogen to deliver, in a single step, effector proteins for modulation of host-cell functions into the human host cell cytosol to establish a unique intracellular niche for replication. The translocon proteins located at the top of the T3SS needle filament are essential for its function, as they form pores in the host-cell membrane. Interestingly, unlike other Gram-negative bacteria, C. pneumoniae has two putative translocon operons, named LcrH_1 and LcrH_2. However, little is known about chlamydial translocon proteins. In this study, we analyzed CPn0809, one of the putative hydrophobic translocators encoded by the LcrH_1 operon, and identified an 'SseC-like family' domain characteristic of T3S translocators. Using bright-field and confocal microscopy, we found that CPn0809 is associated with EBs during early and very late phases of a C. pneumoniae infection. Furthermore, CPn0809 forms oligomers, and interacts with the T3SS chaperone LcrH_1, via its N-terminal segment. Moreover, expression of full-length CPn0809 in the heterologous host Escherichia coli causes a grave cytotoxic effect that leads to cell death. Taken together, our data indicate that CPn0809 likely represents one of the translocon proteins of the C. pneumoniae T3SS, and possibly plays a role in the translocation of effector proteins in the early stages of infection.

  4. Telling partners about chlamydia: how acceptable are the new technologies?

    Directory of Open Access Journals (Sweden)

    Parker Rhian M

    2010-03-01

    Full Text Available Abstract Background Partner notification is accepted as a vital component in the control of chlamydia. However, in reality, many sexual partners of individuals diagnosed with chlamydia are never informed of their risk. The newer technologies of email and SMS have been used as a means of improving partner notification rates. This study explored the use and acceptability of different partner notification methods to help inform the development of strategies and resources to increase the number of partners notified. Methods Semi-structured telephone interviews were conducted with 40 people who were recently diagnosed with chlamydia from three sexual health centres and two general practices across three Australian jurisdictions. Results Most participants chose to contact their partners either in person (56% or by phone (44%. Only 17% chose email or SMS. Participants viewed face-to-face as the "gold standard" in partner notification because it demonstrated caring, respect and courage. Telephone contact, while considered insensitive by some, was often valued because it was quick, convenient and less confronting. Email was often seen as less personal while SMS was generally considered the least acceptable method for telling partners. There was also concern that emails and SMS could be misunderstood, not taken seriously or shown to others. Despite these, email and SMS were seen to be appropriate and useful in some circumstances. Letters, both from the patients or from their doctor, were viewed more favourably but were seldom used. Conclusion These findings suggest that many people diagnosed with chlamydia are reluctant to use the new technologies for partner notification, except in specific circumstances, and our efforts in developing partner notification resources may best be focused on giving patients the skills and confidence for personal interaction.

  5. Chlamydia trachomatis infection and maternal outcomes in Southern Ghana

    OpenAIRE

    2016-01-01

    Background: Despite the fact that Chlamydia trachomatis (CT) infection in pregnancy is known to have grave impact on maternal and neonatal health, routine CT screening in pregnancy is not available in Ghana The main aim of this study was to determine the prevalence and adverse maternal outcomes of CT infection among pregnant women attending antennal clinic at the Cape Coast Teaching Hospital. Methods: Two hundred and thirty two (232) pregnant women screened for CT infection by PCR were pur...

  6. Chlamydia trachomatis and oral contraceptive use: a quantitative review.

    OpenAIRE

    Cottingham, J.; Hunter, D.

    1992-01-01

    OBJECTIVES--Chlamydia trachomatis is now recognised as a major sexually transmitted disease; oral contraceptive use is rapidly increasing particularly in developing countries. There are thus important public health implications of the many reports that isolation of C trachomatis is more frequent among users of oral contraceptives. The aim of this analysis was to assess the strength and consistency of this association by summarising published studies between 1972 and 1990. DESIGN--Studies iden...

  7. Modelling the impact of chlamydia screening on the transmission of HIV among men who have sex with men

    NARCIS (Netherlands)

    Xiridou, Maria; Vriend, Henrike J.; Lugner, Anna K.; Wallinga, Jacco; Fennema, Johannes S.; Prins, Jan M.; Geerlings, Suzanne E.; Rijnders, Bart J.A.; Prins, Maria; de Vries, Henry J.C.; Postma, Maarten J.; van Veen, Maaike G.; Schim van der Loeff, Maarten F.; van der Sande, Marianne A.B.

    2013-01-01

    Background: Recent studies have found high prevalences of asymptomatic rectal chlamydia among HIV-infected men who have sex with men (MSM). Chlamydia could increase the infectivity of HIV and the susceptibility to HIV infection. We investigate the role of chlamydia in the spread of HIV among MSM and

  8. Modelling the impact of chlamydia screening on the transmission of HIV among men who have sex with men

    NARCIS (Netherlands)

    M. Xiridou (Maria); H.J. Vriend (Henrike); A.K. Lugnér (Anna); J. Wallinga (Jacco); J.S.A. Fennema (Johan); J.M. Prins (Jan); S.E. Geerlings (Suzanne); B.J.A. Rijnders (Bart); M. Prins (Mariia); H.J.C. de Vries (Henry); M.J. Postma (Maarten); M.G. van Veen (Maaike); M. Schim van der Loeff (Maarten); M.A.B. van der Sande (Marianne)

    2013-01-01

    textabstractBackground: Recent studies have found high prevalences of asymptomatic rectal chlamydia among HIV-infected men who have sex with men (MSM). Chlamydia could increase the infectivity of HIV and the susceptibility to HIV infection. We investigate the role of chlamydia in the spread of HIV a

  9. Quantitative Detection of Chlamydia psittaci and C. pecorum by High-Sensitivity Real-Time PCR Reveals High Prevalence of Vaginal Infection in Cattle

    OpenAIRE

    DeGraves, Fred J.; Gao, Dongya; Hehnen, Hans-Robert; Schlapp, Tobias; Kaltenboeck, Bernhard

    2003-01-01

    Bovine vaginal cytobrush specimens were analyzed for the presence of Chlamydia spp. by a high-sensitivity, high-specificity quantitative PCR. The 53% prevalence of low-level Chlamydia psittaci and C. pecorum genital infection detected in virgin heifers suggests predominantely extragenital transmission of Chlamydia in cattle and conforms to the high seroprevalence of anti-Chlamydia antibodies.

  10. Chlamydia trachomatis Infections during Pregnancy: Consequences for pregnancy outcome and infants

    NARCIS (Netherlands)

    G.I.J.G. Rours (Ingrid)

    2010-01-01

    textabstractChlamydia trachomatis is the most common bacterial sexually transmitted infection (STI) worldwide. Chlamydia is responsible for a significant proportion of genitourinary tract infections in adult males and females, but like STIs in general, it is primarily a woman’s health care issue sin

  11. Innate immune responses to Chlamydia pneumoniae infection: role of TLRs, NLRs, and the inflammasome.

    Science.gov (United States)

    Shimada, Kenichi; Crother, Timothy R; Arditi, Moshe

    2012-11-01

    Chlamydiae are important human pathogens that are responsible for a wide rage of diseases with a significant impact on public health. In this review article we highlight how recent studies have increased our knowledge of Chlamydia pneumoniae pathogenesis and mechanisms of innate immunity directed host defense against C. pneumoniae infection.

  12. Enhanced chlamydia surveillance in New South Wales (Australia) prisons, 2005-2007.

    Science.gov (United States)

    Forrest, Garry; Boonwaat, Leng; Douglas, Jenny; Awofeso, Niyi

    2009-01-01

    Chlamydia is currently the most frequently notified infectious disease in New South Wales (NSW). Published articles relating to chlamydia prevalence in Australian prison settings are sparse, but studies from the United Kingdom and the United States indicate relatively high chlamydia prevalence among young incarcerated individuals. This article reports on findings from an enhanced chlamydia surveillance programme in NSW prisons between 2005 and 2007. The authors report a relatively low chlamydia prevalence among the general population of NSW prisoners (compared with figures from the United Kingdom and United States), which by the end of 2007 was 4%. The average crude chlamydia notification rate for the NSW prison population during the review period was about four times that of the general NSW community - 716/100,000 during the review period compared with 175/100,000 in the NSW general community. The average crude chlamydia notification rate for Aboriginal prisoners during the review period was 1262/100,000, compared with 1470/100,000 in the general Australian Aboriginal population. The authors grapple with the dilemma of expanding chlamydia screening and treatment services for the sexual health benefits of prison populations with static prison health budgets on one hand, and limited evidence of cost-effectiveness of such an expensive intervention on the other.

  13. Two more species of Chlamydia-does it make a difference?

    Science.gov (United States)

    Sachse, Konrad; Laroucau, Karine

    2015-02-01

    The recent description of Chlamydia (C.) avium and C. gallinacea as new species of the reunited genus Chlamydia can be expected to have implications on the perception of avian chlamydiosis. We discuss possible effects on epidemiology, diagnosis and our understanding of aetiopathogenesis resulting from this discovery.

  14. Analysis of the humoral immune response to Chlamydia outer membrane protein 2

    DEFF Research Database (Denmark)

    Mygind, P; Christiansen, Gunna; Persson, K;

    1998-01-01

    The humoral immune response to Chlamydia outer membrane protein 2 (Omp2) was studied. Omp2 is a highly genus-conserved structural protein of all Chlamydia species, containing a variable N-terminal fragment. To analyze where the immunogenic parts were localized, seven highly purified truncated...

  15. Topological analysis of Chlamydia trachomatis L2 outer membrane protein 2

    DEFF Research Database (Denmark)

    Mygind, P; Christiansen, Gunna; Birkelund, Svend

    1998-01-01

    Using monospecific polyclonal antisera to different parts of Chlamydia trachomatis L2 outer membrane protein 2 (Omp2), we show that the protein is localized at the inner surface of the outer membrane. Omp2 becomes immunoaccessible when Chlamydia elementary bodies are treated with dithiothreitol...

  16. The prevalence and clinical significance of Chlamydia infection in island and mainland populations of Victorian koalas (Phascolarctos cinereus).

    Science.gov (United States)

    Patterson, Jade L S; Lynch, Michael; Anderson, Garry A; Noormohammadi, Amir H; Legione, Alistair; Gilkerson, James R; Devlin, Joanne M

    2015-04-01

    Chlamydia infection is known to impact the health of koalas (Phascolarctos cinereus) in New South Wales (NSW) and Queensland, but the clinical significance of Chlamydia infections in Victorian koalas is not well described. We examined the prevalence of Chlamydia infection and assessed associated health parameters in two Victorian koala populations known to be Chlamydia positive. The same testing regimen was applied to a third Victorian population in which Chlamydia had not been detected. We examined 288 koalas and collected samples from the urogenital sinus and conjunctival sacs. Detection and differentiation of Chlamydia species utilized real-time PCR and high-resolution melting curve analysis. Chlamydia pecorum was detected in two populations (prevalences: 25% and 41%, respectively) but only from urogenital sinus swabs. Chlamydia was not detected in the third population. Chlamydia pneumoniae was not detected. Chlamydia pecorum infection was positively associated with wet bottom (indicating chronic urinary tract disease) in one Chlamydia-positive population and with abnormal urogenital ultrasound findings in the other Chlamydia-positive population. The prevalence of wet bottom was similar in all populations (including the Chlamydia-free population), suggesting there is another significant cause (or causes) of wet bottom in Victorian koalas. Ocular disease was not observed. This is the largest study of Chlamydia infection in Victorian koalas, and the results suggest the potential for epidemiologic differences related to Chlamydia infections between Victorian koalas and koalas in Queensland and NSW and also between geographically distinct Victorian populations. Further studies to investigate the genotypes of C. pecorum present in Victorian koalas and to identify additional causes of wet bottom in koalas are indicated.

  17. Role of Diatoms in the Spatial-Temporal Distribution of Intracellular Nitrate in Intertidal Sediment

    DEFF Research Database (Denmark)

    Stief, P.; Kamp, A.; de Beer, D.

    2013-01-01

    Intracellular nitrate storage allows microorganisms to survive fluctuating nutrient availability and anoxic conditions in aquatic ecosystems. Here we show that diatoms, ubiquitous and highly abundant microalgae, represent major cellular reservoirs of nitrate in an intertidal flat of the German...

  18. Comprehensive insights into transcriptional adaptation of intracellular mycobacteria by microbe-enriched dual RNA sequencing

    NARCIS (Netherlands)

    Rienksma, R.A.; Suarez Diez, M.; Mollenkopf, H.J.; Dolganov, G.M.; Dorhoi, A.; Schoolnik, G.K.; Martins Dos Santos, V.A.P.; Kaufmann, S.; Schaap, P.J.; Gengenbacher, M.

    2015-01-01

    BackgroundThe human pathogen Mycobacterium tuberculosis has the capacity to escape eradication by professional phagocytes. During infection, M. tuberculosis resists the harsh environment of phagosomes and actively manipulates macrophages and dendritic cells to ensure prolonged intracellular survival

  19. Risk profile for Chlamydia infection in women from public health clinics in New York State.

    Science.gov (United States)

    Han, Y; Morse, D L; Lawrence, C E; Murphy, D; Hipp, S

    1993-02-01

    The prevalence of chlamydial infection and associated risk factors were studied in 1531 women from ten clinics in New York State excluding New York City. Overall Chlamydia infection rates were 13.6%; 17.6% in eight high risk family planning and STD clinics, and 5.7% in two low risk college and private clinics. Risk factors for Chlamydia infection included: age oral contraceptives (odds ratio 2.0), a history of having more than one sexual partner (odds ratio 1.7) and, in one clinic where data was available, inflammation on Papanicolaou smears (odds ratio 2.1). These data helped secure funding for Chlamydia preventive services and permitted development of a risk profile (score card) of Chlamydia for each age group. Use of such a score card can be most helpful in assigning which patients could benefit most from Chlamydia cultures, especially in those areas where testing is unavailable or too costly to screen all patients.

  20. Evidence of a conserved role for Chlamydia HtrA in the replication phase of the chlamydial developmental cycle.

    Science.gov (United States)

    Patel, Pooja; De Boer, Leonore; Timms, Peter; Huston, Wilhelmina May

    2014-08-01

    Identification of the HtrA inhibitor JO146 previously enabled us to demonstrate an essential function for HtrA during the mid-replicative phase of the Chlamydia trachomatis developmental cycle. Here we extend our investigations to other members of the Chlamydia genus. C. trachomatis isolates with distinct replicative phase growth kinetics showed significant loss of viable infectious progeny after HtrA was inhibited during the replicative phase. Mid-replicative phase addition of JO146 was also significantly detrimental to Chlamydia pecorum, Chlamydia suis and Chlamydia cavie. These data combined indicate that HtrA has a conserved critical role during the replicative phase of the chlamydial developmental cycle.

  1. Chlamydia Screening in Ireland: a pilot study of opportunistic screening for genital Chlamydia trachomatis infection in Ireland (2007-2009). Summary Integrated Report

    OpenAIRE

    Balfe, Myles; Brugha, Ruairi; O'Connell, Emer; Vaughan, Deirdre; O'Donovan, Diarmuid; Coleman, Claire; Conroy, Ronán; Cormican, Martin; Fitzgerald, Margaret; Fleming, Catherine; McGee, Hannah; Murphy, Andrew; Ni Fhoghlu, Grainne; O'Neill, Ciaran; Gillespie, Paddy

    2012-01-01

    Genital Chlamydia trachomatis (CT) infection is the most common curable, bacterial sexually transmitted infection (STI) worldwide [1, 2]. The number of cases notified in Ireland increased from 3,353 in 2005 to 5,781 in 2009 [3]. Notifications have increased since 2004 when legislation requiring laboratory notification came into effect. Chlamydia is usually a ‘silent’ asymptomatic infection, spread without the knowledge of those transmitting and contracting it: most cases remain undetected and...

  2. Systems Biology Approaches for the Prediction of Possible Role of Chlamydia pneumoniae Proteins in the Etiology of Lung Cancer.

    Science.gov (United States)

    Khan, Shahanavaj; Imran, Ahamad; Khan, Abdul Arif; Abul Kalam, Mohd; Alshamsan, Aws

    2016-01-01

    Accumulating evidence has recently supported the association of bacterial infection with the growth and development of cancers, particularly in organs that are constantly exposed to bacteria such as the lungs, colon, cervical cancer etc. Our in silico study on the proteome of Chlamydia pneumoniae suggests an unprecedented idea of the etiology of lung cancer and have revealed that the infection of C. pneumoniae is associated with lung cancer development and growth. It is reasonable to assume that C. pneumoniae transports its proteins within host-intracellular organelles during infection, where they may work with host-cell proteome. The current study was performed for the prediction of nuclear targeting protein of C. pneumoniae in the host cell using bioinformatics predictors including ExPASy pI/Mw tool, nuclear localization signal (NLS) mapper, balanced sub cellular localization predictor (BaCeILo), and Hum-mPLoc 2.0. We predicted 47/1112 nuclear-targeting proteins of C. pneumoniae connected with several possible alterations in host replication and transcription during intracellular infection. These nuclear-targeting proteins may direct to competitive interactions of host and C. pneumoniae proteins with the availability of same substrate and may be involved as etiological agents in the growth and development of lung cancer. These novel findings are expected to access in better understanding of lung cancer etiology and identifying molecular targets for therapy.

  3. Pmp-like proteins Pls1 and Pls2 are secreted into the lumen of the Chlamydia trachomatis inclusion.

    Science.gov (United States)

    Jorgensen, Ine; Valdivia, Raphael H

    2008-09-01

    The obligate intracellular pathogen Chlamydia trachomatis secretes effector proteins across the membrane of the pathogen-containing vacuole (inclusion) to modulate host cellular functions. In an immunological screen for secreted chlamydial proteins, we identified CT049 and CT050 as potential inclusion membrane-associated proteins. These acidic, nonglobular proteins are paralogously related to the passenger domain of the polymorphic membrane protein PmpC and, like other Pmp proteins, are highly polymorphic among C. trachomatis ocular and urogenital strains. We generated antibodies to these Pmp-like secreted (Pls) proteins and determined by immunofluorescence microscopy that Pls1 (CT049) and Pls2 (CT050) localized to globular structures within the inclusion lumen and at the inclusion membrane. Fractionation of membranes and cytoplasmic components from infected cells by differential and density gradient centrifugation further indicated that Pls1 and Pls2 associated with membranes distinct from the bulk of bacterial and inclusion membranes. The accumulation of Pls1 and, to a lesser extent, Pls2 in the inclusion lumen was insensitive to the type III secretion inhibitor C1, suggesting that this translocation system is not essential for Pls protein secretion. In contrast, Pls secretion and stability were sensitive to low levels of beta-lactam antibiotics, suggesting that a functional cell wall is required for Pls secretion from the bacterial cell. Finally, we tested the requirement for these proteins in Chlamydia infection by microinjecting anti-Pls1 and anti-Pls2 antibodies into infected cells. Coinjection of anti-Pls1 and -Pls2 antibodies partially inhibited expansion of the inclusion. Because Pls proteins lack classical sec-dependent secretion signals, we propose that Pls proteins are secreted into the inclusion lumen by a novel mechanism to regulate events important for chlamydial replication and inclusion expansion.

  4. Assessment of Chlamydia psittaci Shedding and Environmental Contamination as Potential Sources of Worker Exposure throughout the Mule Duck Breeding Process.

    Science.gov (United States)

    Hulin, V; Bernard, P; Vorimore, F; Aaziz, R; Cléva, D; Robineau, J; Durand, B; Angelis, L; Siarkou, V I; Laroucau, K

    2015-12-28

    Chlamydia psittaci is an obligate intracellular bacterium responsible for avian chlamydiosis, otherwise known as psittacosis, a zoonotic disease that may lead to severe atypical pneumonia. This study was conducted on seven mule duck flocks harboring asymptomatic birds to explore the circulation and persistence of C. psittaci during the entire breeding process and assess the potential sources of worker exposure. Cloacal swabs and air samples were taken on each occasion requiring humans to handle the birds. In parallel, environmental samples, including dust, water, and soil, were collected. Specific real-time PCR analyses revealed the presence of C. psittaci in all flocks but with three different shedding patterns involving ducks about the age of 4, 8, and 12 weeks with heavy, moderate, and low excretion levels, respectively. Air samples were only positive in flocks harboring heavy shedders. Dust in flocks with heavy or moderate shedders carried chlamydial loads strongly associated with the loads detected in avian and soil samples. Environmental contamination, significantly correlated with shedding dynamics, was considered to be the most probable source of exposure. The high prevalence of bacteriophage Chp1 in all flocks, mostly jointly present with chlamydia, suggests an important factor in C. psittaci persistence, thus creating a greater risk for humans. A survey conducted in these flocks regarding farming practices and activities showed that disinfection seems to be the most promising practice for reducing C. psittaci prevalence in ducks and that the place and the duration of action during operations seem to be potential risk factors. Strict adherence to good practices is strongly recommended.

  5. Investigations concerning the prevalence of Coxiella burnetii and Chlamydia abortus in sheep in correlation with management systems and abortion rate in Lower Saxony in 2004.

    Science.gov (United States)

    Runge, Martin; Binder, Alfred; Schotte, Ulrich; Ganter, Martin

    2012-01-01

    The intracellular bacteria Coxiella (C) burnetii and Chlamydia (Chl) abortus induce abortion in sheep and also affect humans. While Chl. abortus only infrequently infects humans, C burnetii is the aetiological agent of numerous Q fever outbreaks during the last decades. There is only limited knowledge about the prevalence of both pathogens in sheep, although sheep are involved in almost all Q fever outbreaks in Germany. The aim of our study was to investigate the prevalence of both pathogens in flocks located in Lower Saxony, Germany, in correlation to the management form and abortion rate. Serum samples of 1714 sheep from 95 flocks located in Lower Saxony were investigated by ELISA. 2.7% of these samples were positive, 1.3% showed inconclusive results in the C. burnetii-ELISA. Elevated intra-flock seroprevalences were only detected in three migrating flocks. Chlamydia-specific antibodies could be detected in 15.1% serum samples of mainly shepherded and migrating flocks. In one of these flocks with a high intra-flock seroprevalence for C burnetii (27%) and Chlamydia (44.9%), C burnetii was detected in 21.6% of the placenta samples of normal births and in 12.5% of the colostrum samples by PCR. Aborted fetuses and the corresponding placentas were negative in C burnetii-PCR, but in most of them and also in many other placenta samples Chl. abortus could be detected by PCR and DNA microarray. This survey shows a low overall prevalence of C. burnetii in sheep in Lower Saxony in the year 2004. However, three migrating flocks with a high intra-flock prevalence are localized in the southern parts of Lower Saxony. Spreading of C burnetii could occur, because of the large radius of grazing of all three flocks.

  6. Autophagic clearance of bacterial pathogens: molecular recognition of intracellular microorganisms.

    Science.gov (United States)

    Pareja, Maria Eugenia Mansilla; Colombo, Maria I

    2013-01-01

    Autophagy is involved in several physiological and pathological processes. One of the key roles of the autophagic pathway is to participate in the first line of defense against the invasion of pathogens, as part of the innate immune response. Targeting of intracellular bacteria by the autophagic machinery, either in the cytoplasm or within vacuolar compartments, helps to control bacterial proliferation in the host cell, controlling also the spreading of the infection. In this review we will describe the means used by diverse bacterial pathogens to survive intracellularly and how they are recognized by the autophagic molecular machinery, as well as the mechanisms used to avoid autophagic clearance.

  7. Chlamydia-related abortions in cattle from Graubunden, Switzerland.

    Science.gov (United States)

    Borel, N; Thoma, R; Spaeni, P; Weilenmann, R; Teankum, K; Brugnera, E; Zimmermann, D R; Vaughan, L; Pospischil, A

    2006-09-01

    In 2001, the first case of bovine chlamydial abortion was reported in canton Graubunden, Switzerland. In this region, Chlamydophila (Cp.) abortus is endemic in small ruminants. Hence, we aimed to investigate the incidence of chlamydia-related abortions in cattle from Graubunden. During breeding seasons of 2003-2004, formalin-fixed and paraffin-embedded placenta specimens (n = 235) from late-term abortions in cattle were analyzed by histopathology, immunohistochemistry with a Chlamydiaceae-specific monoclonal antibody against chlamydial lipopolysaccharide (LPS), and 2 different polymerase chain reaction (PCR) methods (16 S ribosomal ribonucleic acid [rRNA] PCR, intergenic spacer [IGS-S] PCR), followed by PCR product sequencing. In 149 of 235 cases (63.4%), histopathologic lesions such as purulent and/or necrotizing placentitis were observed. Chlamydial antigen was clearly demonstrated in immunohistochemistry in only 1 of 235 cases (0.4%). Cp. abortus or Cp. psittaci was found in 12 of 235 (5.1%) and 10 of 235 cases (4.2%) by 16 S rRNA PCR and IGS-S PCR, respectively. However, we detected, by 16 S rRNA PCR, 43 of 235 cases (18.3%) to be positive for chlamydia-like organisms. In contrast to the situation in small ruminants in the canton Graubunden, bovine abortion from Cp. abortus seems not to play an important role. Nevertheless, zoonotic potential should be taken into account when handling abortion material from cattle. The significance of chlamydia-like isolates other than Waddlia chondrophila remains an open question in abortion and needs further investigation.

  8. Association between chlamydia pneumoniae infection and carotid atherosclerotic plaques

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    Fereshteh Ashtari

    2007-08-01

    Full Text Available BACKGROUND: Several studies have suggested an association between Chlamydia pneumonia infection and atherosclerosis. This study was designed to investigate the association between this organism and atherosclerotic plaque formation in right and left common carotid arteries (CCAs and extracranial portions of internal carotid arteries (ICAs.
    METHODS: Antibodies to Chlamydia pneumoniae (IgA and IgG were measured and compared in 42 patients who had plaque in at least one CCA or ICA (detected by duplex ultrasound and 82 patients without any plaque in these arteries. Cp.IgG and Cp.IgA titers over 1.10 ISR were defined to be positive.
    RESULTS: We found that 6.1% of control subjects and 16.7% of cases were Cp.IgA seropositive. The difference between these two groups was prominent but was not statistically significant (P = 0.104. 4.2% of females without atherosclerotic plaque and 31.6% of females with plaque were Cp.IgA seropositive. This difference is statistically significant (P = 0.005. There was no significant difference in seropositivity of Cp.IgG between case and control subjects or in male and female groups with or without plaque.
    CONCLUSIONS: Cp.IgA is a predictor of atherosclerosis in women, but Cp.IgG has no predictive value for plaque formation in either gender.
    KEY WORDS: Atherosclerotic plaque, Chlamydia pneumoniae, serum antibody.

  9. Correlation of Chlamydia pneumoniae infection with primary biliary cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Hai-Ying Liu; An-Mei Deng; Jian Zhang; Ye Zhou; Ding-Kang Yao; Xiao-Qing Tu; Lie-Ying Fan; Ren-Qian Zhong

    2005-01-01

    AIM: To evaluate the association between Chlamydia pneumoniae (Cpn) infection and primary biliary cirrhosis (PBC).METHODS: Cpn IgG and IgM were determined by enzymelinked immunosorbent assay (ELISA) in 41 well-established PBC patients and two race-matched control groups (posthepatitis cirrhosis, n = 70; healthy controls, n = 57).RESULTS: The mean level and seroprevalence of Cpn IgG in PBC group and post-hepatitis cirrhosis (PHC) group were significantly higher than those in healthy controls (46.8±43.4 RU/mL, 49.5±45.2 RU/mL vs28.3±32.7 RU/mL;68.3%, 71.4%, 42.1%, respectively; P<0.05). There was a remarkably elevated seroprevalence of Cpn IgM in patients with PBC (22.0%) compared to the PHC and healthy control (HC) groups. For the PBC patients versus the HCs, the odds ratios (ORs) of the presence of Cpn IgG and IgM were 2.7 (95% CI 0.9-6.1) and 5.1 (95% CI 1.4-18.5), respectively. Though there was no correlation in the level of Cpn IgG with total IgG in sera of patients with PBC (r = -0.857, P = 0.344>0.05), Cpn IgM was related with the abnormally high concentrations of total IgM in PBC group.CONCLUSION: The results of this study do not support the hypothesis that infection with Chlamydia pneumoniae may be a triggering agent or even a causative agent in PBC, but suggest that Chlamydia pneumoniae infection probably contributes to the high level of IgM present in most patients with PBC.

  10. Chlamydia screening and positivity in juvenile detention centers, United States, 2009-2011.

    Science.gov (United States)

    Satterwhite, Catherine Lindsey; Newman, Daniel; Collins, Dayne; Torrone, Elizabeth

    2014-01-01

    An estimated 2.9 million new chlamydia infections occur in the United States each year. Among women, chlamydia can lead to serious adverse outcomes, including pelvic inflammatory disease and infertility. Chlamydia prevalence is highest among females aged 15-19 years. Despite long-standing recommendations directed at young, sexually active females, screening remains sub-optimal. Juvenile detention centers (JDCs) are uniquely situated to screen and treat high-risk adolescents. From 2009-2011, performance measure data on chlamydia screening coverage (proportion of eligible females screened) and positivity (proportion of females tested who were positive) were available from 126 geographically-dispersed JDCs in the United States. These facilities reported screening 55.2% of females entering the facilities (149,923), with a facility-specific median of 66.4% (range: 0-100%). Almost half (44.4%) of facilities had screening coverage levels of 75-100%. This screening resulted in the detection of 12,305 chlamydial infections, for an overall positivity of 14.7% (facility-specific median = 14.9%, range: 0-36.9%). In linear regression analysis, chlamydia positivity was inversely associated with screening coverage: as coverage increased, positivity decreased. The burden of chlamydia in JDCs is substantial; facilities should continue to deliver recommended chlamydia screening and treatment to females and identify mechanisms to increase coverage.

  11. Comparing two definitions of ethnicity for identifying young persons at risk for chlamydia.

    Science.gov (United States)

    Haasnoot, A; Koedijk, F D H; Op De Coul, E L M; Götz, H M; van der Sande, M A B; Van Den Broek, I V F

    2012-05-01

    Ethnic disparities in chlamydia infections in The Netherlands were assessed, in order to compare two definitions of ethnicity: ethnicity based on country of birth and self-defined ethnicity. Chlamydia positivity in persons aged 16-29 years was investigated using data from the first round of the Chlamydia Screening Implementation (CSI, 2008-2009) and surveillance data from STI centres (2009). Logistic regression modelling showed that being an immigrant was associated with chlamydia positivity in both CSI [adjusted odds ratio (aOR) 2·3, 95% confidence interval (CI) 2·0-2·6] and STI centres (aOR 1·4, 95% CI 1·3-1·5). In both settings, 60% of immigrants defined themselves as Dutch. Despite the difference, classification by self-defined ethnicity resulted in similar associations between (non-Dutch) ethnicity and chlamydia positivity. However, ethnicity based on country of birth explained variation in chlamydia positivity better, and is objective and constant over time and therefore more useful for identifying young persons at higher risk for chlamydia infection.

  12. Forekomst af Chlamydia trachomatis hos værnepligtige

    DEFF Research Database (Denmark)

    Søgaard, P; Møller, B R; Thorsen, Poul;

    1996-01-01

    (VD) and actual symptoms of urethritis and cervicitis. EIA positive specimens were confirmed by immunofluorescent microscopy. The investigation comprised 831 men and 80 women (17-26 years). The prevalence was 5.7% (95% confidence limits 4.2-7.4%) and 15% (8-25%) for men and women, respectively (p ... among Chlamydia positive men was 6. The frequency of earlier VD was 7.5% and 10% among men and women, respectively. Treatment with tetracycline was effective, which makes control of eradication unnecessary. We conclude that genital chlamydial infection among young asymptomatic people is common...

  13. Chlamydia in women: a case for more action?

    Science.gov (United States)

    1986-04-19

    The 1985 Communicable Disease Surveillance Center figures for sexually transmitted diseases document over 14,000 confirmed cases of genital chlamydial infection in women. Yet, this figure seriously underestimates the size of the problem as many chlamydial infections are silent. The mainstay of diagnosis until recently has been isolation of C. trachomatis in cell culture, which is time consuming, technically demanding, expensive, and available in only a few centers. A firm diagnosis of chlamydial infection cannot be based on serology alone. Antibodies can be detected in 78-100% of womn with C. trachomatis in the cervix, but in those who are culture negative 31-87% also will have antibodies. More support is given to the diagnosis by demonstration of a rising titre of IgG antibody or by detection of IgM, but because of the late presentation of most women with chlamydia this is seldom possible. Newer tests include direct immunofluorescence statining of genital secretions which is rapid and simple. Results of this method compare favorably with those of cell culture, but screening large numbers of smears is expensive and tedious. Enzyme-linked immunosorbent assays also give good results. C trachomatis is a well known cause of cervicitis and salpingitis and is consequently a major factor in infertility. The frequency of chlamydial infection is influenced by sexual activity and promiscuity, but the effect of contraceptive choice is more difficult to determine. An IUD can provide a nidus for many infections, but the role of oral contraceptives (OCs) is more controversial. Instrumentation of the endocervical canal provides a route for introduction of infection, which is therefore a frequent and important complication of induced abortion. Westergaard et al. in a study of women having 1st trimester abortions found that 10% had symptomless cervical chlamydia; postabortal pelvic inflammatory disease developed in 28% of these patients by comparison with 10% in culture

  14. Urogenital Chlamydia trachomatis infections among ethnic groups in Paramaribo, Suriname; determinants and ethnic sexual mixing patterns.

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    Jannie J van der Helm

    Full Text Available BACKGROUND: Little is known about the epidemiology of urogenital Chlamydia trachomatis infection (chlamydia in Suriname. Suriname is a society composed of many ethnic groups, such as Creoles, Maroons, Hindustani, Javanese, Chinese, Caucasians, and indigenous Amerindians. We estimated determinants for chlamydia, including the role of ethnicity, and identified transmission patterns and ethnic sexual networks among clients of two clinics in Paramaribo, Suriname. METHODS: Participants were recruited at two sites a sexually transmitted infections (STI clinic and a family planning (FP clinic in Paramaribo. Urine samples from men and nurse-collected vaginal swabs were obtained for nucleic acid amplification testing. Logistic regression analysis was used to identify determinants of chlamydia. Multilocus sequence typing (MLST was performed to genotype C. trachomatis. To identify transmission patterns and sexual networks, a minimum spanning tree was created, using full MLST profiles. Clusters in the minimum spanning tree were compared for ethnic composition. RESULTS: Between March 2008 and July 2010, 415 men and 274 women were included at the STI clinic and 819 women at the FP clinic. Overall chlamydia prevalence was 15% (224/1508. Age, ethnicity, and recruitment site were significantly associated with chlamydia in multivariable analysis. Participants of Creole and Javanese ethnicity were more frequently infected with urogenital chlamydia. Although sexual mixing with other ethnic groups did differ significantly per ethnicity, this mixing was not independently significantly associated with chlamydia. We typed 170 C. trachomatis-positive samples (76% and identified three large C. trachomatis clusters. Although the proportion from various ethnic groups differed significantly between the clusters (P = 0.003, all five major ethnic groups were represented in all three clusters. CONCLUSION: Chlamydia prevalence in Suriname is high and targeted prevention

  15. Management of Chlamydia trachomatis genital tract infection: screening and treatment challenges

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    Brandie D Taylor

    2011-01-01

    Full Text Available Brandie D Taylor, Catherine L HaggertyUniversity of Pittsburgh, Department of Epidemiology, Pittsburgh, PA, USAAbstract: Chlamydia trachomatis is a prevalent sexually transmitted infection that can lead to serious reproductive morbidity. Management and control of C. trachomatis is a challenge, largely due to its asymptomatic nature and our incomplete understanding of its natural history. Although chlamydia screening programs have been implemented worldwide, several countries have observed increasing rates of reported chlamydia cases. We reviewed the literature relating to the long-term complications of C. trachomatis, as well as screening strategies, treatment, and prevention strategies for reducing chlamydia in the population. Articles from 1950–2010 were identified through a Medline search using the keyword “Chlamydia trachomatis” combined with “screening”, “pelvic inflammatory disease”, “endometritis”, “salpingitis”, “infertility”, "ectopic pregnancy”, “urethritis”, “epididymitis”, “proctitis”, “prostatitis”, “reinfection”, “cost-effectiveness”, “treatment”, “vaccines”, or “prevention”. Progression of C. trachomatis varies, and recurrent infections are common. Currently, there is limited evidence on the effectiveness of chlamydia screening. Higher quality studies are needed to determine the efficacy of more frequent screening, on a broader range of sequelae, including infertility and ectopic pregnancy, in addition to pelvic inflammatory disease. Studies should focus on delineating the natural history of recurrent infections, paying particular attention to treatment failures. Furthermore, alternatives to screening, such as vaccines, should continue to be explored.Keywords: Chlamydia trachomatis, sexually transmitted disease, chlamydia screening, chlamydia treatment

  16. Comparison of the population excess fraction of Chlamydia trachomatis infection on pelvic inflammatory disease at 12-months in the presence and absence of chlamydia testing and treatment: Systematic review and retrospective cohort analysis

    Science.gov (United States)

    Turner, Katy M. E.; Leung, Stella; Yu, B. Nancy; Frølund, Maria; Benfield, Thomas; Blanchard, James; Westh, Henrik; Ward, Helen

    2017-01-01

    Background The impact of Chlamydia trachomatis (chlamydia) control on the incidence of pelvic inflammatory disease (PID) is theoretically limited by the proportion of PID caused by chlamydia. We estimate the population excess fraction (PEF) of treated chlamydia infection on PID at 12-months in settings with widespread chlamydia control (testing and treatment) and compare this to the estimated PEF of untreated chlamydia. Methods We used two large retrospective population-based cohorts of women of reproductive age from settings with widespread chlamydia control to calculate the PEF of treated chlamydia on PID at 12-months. We undertook a systematic review to identify further studies that reported the risk of PID in women who were tested for chlamydia (infected and uninfected). We used the same method to calculate the PEF in eligible studies then compared all estimates of PEF. Results The systematic review identified a single study, a randomised controlled trial of chlamydia screening (POPI-RCT). In the presence of testing and treatment cases of PID at 12-months per 100,000 women in the untreated setting and 13–184 cases of PID per 100,000 tested women in the presence of testing and treatment. Conclusion Testing and treating chlamydia reduced the PEF of chlamydia on PID by 65% compared to the untreated setting. But in the presence of testing and treatment over 90% of PID could not be attributed to a baseline chlamydia infection. More information is needed about the aetiology of PID to develop effective strategies for improving the reproductive health of women. PMID:28199392

  17. Tissue-Resident T Cells as the Central Paradigm of Chlamydia Immunity.

    Science.gov (United States)

    Johnson, Raymond M; Brunham, Robert C

    2016-04-01

    For almost 2 decades, results from Chlamydia pathogenesis investigations have been conceptualized using a cytokine polarization narrative. Recent viral immunity studies identifying protective tissue-resident memory T cells (Trm) suggest an alternative paradigm based on localized immune networks. As Chlamydia vaccines enter the preclinical pipeline and, in the case of an attenuated trachoma vaccine, are given to human subjects, it may be useful to ask whether cytokine polarization is the appropriate framework for understanding and evaluating vaccine efficacy. In this review, we revisit C. trachomatis pathogenesis data from mice and humans using a Trm narrative and note a comfortable concordance with the Chlamydia pathogenesis literature.

  18. DNA microarray-based detection of multiple pathogens: Mycoplasma spp. and Chlamydia spp.

    Science.gov (United States)

    Schnee, Christiane; Sachse, Konrad

    2015-01-01

    Rapid detection of slow-growing or non-culturable microorganisms, such as Mycoplasma spp. and Chlamydia spp., is still a challenge to diagnosticians in the veterinary field. In addition, as epidemiological evidence on the frequency of mixed infections involving two and more bacterial species has been emerging, detection methods allowing simultaneous identification of different pathogens are required. In the present chapter, we describe DNA microarray-based procedures for the detection of 83 Mollicutes species (Mycoplasma assay) and 11 Chlamydia spp. (Chlamydia assay). The assays are suitable for use in a routine diagnostic environment, as well as in microbiological research.

  19. 'The difference in determinants of Chlamydia trachomatis and Mycoplasma genitalium in a sample of young Australian women.'

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    Walker Sandra

    2011-02-01

    Full Text Available Abstract Background Differences in the determinants of Chlamydia trachomatis ('chlamydia' and Mycoplasma genitalium (MG genital infection in women are not well understood. Methods A cohort study of 16 to 25 year old Australian women recruited from primary health care clinics, aimed to determine chlamydia and MG prevalence and incidence. Vaginal swabs collected at recruitment were used to measure chlamydia and MG prevalence, organism-load and chlamydia-serovar a cross-sectional analysis undertaken on the baseline results is presented here. Results Of 1116 participants, chlamydia prevalence was 4.9% (95% CI: 2.9, 7.0 (n = 55 and MG prevalence was 2.4% (95% CI: 1.5, 3.3 (n = 27. Differences in the determinants were found - chlamydia not MG, was associated with younger age [AOR:0.9 (95% CI: 0.8, 1.0] and recent antibiotic use [AOR:0.4 (95% CI: 0.2, 1.0], and MG not chlamydia was associated with symptoms [AOR:2.1 (95% CI: 1.1, 4.0]. Having two or more partners in last 12 months was more strongly associated with chlamydia [AOR:6.4 (95% CI: 3.6, 11.3] than MG [AOR:2.2 (95% CI: 1.0, 4.6] but unprotected sex with three or more partners was less strongly associated with chlamydia [AOR:3.1 (95%CI: 1.0, 9.5] than MG [AOR:16.6 (95%CI: 2.0, 138.0]. Median organism load for MG was 100 times lower (5.7 × 104/swab than chlamydia (5.6 × 106/swab (p Conclusions These results demonstrate significant chlamydia and MG prevalence in Australian women, and suggest that the differences in strengths of association between numbers of sexual partners and unprotected sex and chlamydia and MG might be due to differences in the transmission dynamics between these infections.

  20. STIM1 Is a Novel Component of ER-Chlamydia trachomatis Inclusion Membrane Contact Sites.

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    Hervé Agaisse

    Full Text Available Productive developmental cycle of the obligate intracellular bacterial pathogen Chlamydia trachomatis depends on the interaction of the replicative vacuole, named the inclusion, with cellular organelles. We have recently reported the formation of ER-Inclusion membrane contact sites (MCSs, where the endoplasmic reticulum (ER is in apposition to the inclusion membrane. These platforms contain the C. trachomatis inclusion membrane protein IncD, the mammalian ceramide transfer protein CERT and the ER resident proteins VAPA/B and were proposed to play a role in the non-vesicular trafficking of lipids to the inclusion. Here, we identify STIM1 as a novel component of ER-Inclusion MCSs. STIM1, an ER calcium (Ca2+ sensor that relocate to ER-Plasma Membrane (PM MCSs upon Ca2+ store depletion, associated with C. trachomatis inclusion. STIM1, but not the general ER markers Rtn3C and Sec61ß, was enriched at the inclusion membrane. Ultra-structural studies demonstrated that STIM1 localized to ER-Inclusion MCSs. Time-course experiments showed that STIM1, CERT and VAPB co-localized throughout the developmental cycle. By contrast, Orai1, the PM Ca2+ channel that interacts with STIM1 at ER-PM MCSs, did not associate with C. trachomatis inclusion. Upon ER Ca2+ store depletion, a pool of STIM1 relocated to ER-PM MCSs, while the existing ER-Inclusion MCSs remained enriched in STIM1. Finally, we have identified the CAD domain, which mediates STIM1-Orai1 interaction, as the minimal domain required for STIM1 enrichment at ER-Inclusion MCSs. Altogether this study identifies STIM1 as a novel component of ER-C. trachomatis inclusion MCSs. We discuss the potential role(s of STIM1 during the infection process.

  1. Diversification and Distribution of Ruminant Chlamydia abortus Clones Assessed by MLST and MLVA.

    Science.gov (United States)

    Siarkou, Victoria I; Vorimore, Fabien; Vicari, Nadia; Magnino, Simone; Rodolakis, Annie; Pannekoek, Yvonne; Sachse, Konrad; Longbottom, David; Laroucau, Karine

    2015-01-01

    Chlamydia abortus, an obligate intracellular bacterium, is the most common infectious cause of abortion in small ruminants worldwide and has zoonotic potential. We applied multilocus sequence typing (MLST) together with multiple-locus variable-number tandem repeat analysis (MLVA) to genotype 94 ruminant C. abortus strains, field isolates and samples collected from 1950 to 2011 in diverse geographic locations, with the aim of delineating C. abortus lineages and clones. MLST revealed the previously identified sequence types (STs) ST19, ST25, ST29 and ST30, plus ST86, a recently-assigned type on the Chlamydiales MLST website and ST87, a novel type harbouring the hemN_21 allele, whereas MLVA recognized seven types (MT1 to MT7). Minimum-spanning-tree analysis suggested that all STs but one (ST30) belonged to a single clonal complex, possibly reflecting the short evolutionary timescale over which the predicted ancestor (ST19) has diversified into three single-locus variants (ST86, ST87 and ST29) and further, through ST86 diversification, into one double-locus variant (ST25). ST descendants have probably arisen through a point mutation evolution mode. Interestingly, MLVA showed that in the ST19 population there was a greater genetic diversity than in other STs, most of which exhibited the same MT over time and geographical distribution. However, the evolutionary pathways of C. abortus STs seem to be diverse across geographic distances with individual STs restricted to particular geographic locations. The ST30 singleton clone displaying geographic specificity and represented by the Greek strains LLG and POS was effectively distinguished from the clonal complex lineage, supporting the notion that possibly two separate host adaptations and hence independent bottlenecks of C. abortus have occurred through time. The combination of MLST and MLVA assays provides an additional level of C. abortus discrimination and may prove useful for the investigation and surveillance of

  2. Diversification and Distribution of Ruminant Chlamydia abortus Clones Assessed by MLST and MLVA.

    Directory of Open Access Journals (Sweden)

    Victoria I Siarkou

    Full Text Available Chlamydia abortus, an obligate intracellular bacterium, is the most common infectious cause of abortion in small ruminants worldwide and has zoonotic potential. We applied multilocus sequence typing (MLST together with multiple-locus variable-number tandem repeat analysis (MLVA to genotype 94 ruminant C. abortus strains, field isolates and samples collected from 1950 to 2011 in diverse geographic locations, with the aim of delineating C. abortus lineages and clones. MLST revealed the previously identified sequence types (STs ST19, ST25, ST29 and ST30, plus ST86, a recently-assigned type on the Chlamydiales MLST website and ST87, a novel type harbouring the hemN_21 allele, whereas MLVA recognized seven types (MT1 to MT7. Minimum-spanning-tree analysis suggested that all STs but one (ST30 belonged to a single clonal complex, possibly reflecting the short evolutionary timescale over which the predicted ancestor (ST19 has diversified into three single-locus variants (ST86, ST87 and ST29 and further, through ST86 diversification, into one double-locus variant (ST25. ST descendants have probably arisen through a point mutation evolution mode. Interestingly, MLVA showed that in the ST19 population there was a greater genetic diversity than in other STs, most of which exhibited the same MT over time and geographical distribution. However, the evolutionary pathways of C. abortus STs seem to be diverse across geographic distances with individual STs restricted to particular geographic locations. The ST30 singleton clone displaying geographic specificity and represented by the Greek strains LLG and POS was effectively distinguished from the clonal complex lineage, supporting the notion that possibly two separate host adaptations and hence independent bottlenecks of C. abortus have occurred through time. The combination of MLST and MLVA assays provides an additional level of C. abortus discrimination and may prove useful for the investigation and

  3. Chlamydia trachomatis Frequency in a Cohort of HPV-Infected Colombian Women.

    Directory of Open Access Journals (Sweden)

    Edith Margarita Quinónez-Calvache

    Full Text Available Chlamydia trachomatis (C. trachomatis, an obligate intracellular bacterium, is the commonest infectious bacterial agent of sexual transmission throughout the world. It has been shown that the presence of this bacteria in the cervix represents a risk regarding HPV persistence and, thereafter, in developing cervical cancer (CC. Prevalence rates may vary from 2% to 17% in asymptomatic females, depending on the population being analysed. This study reports the identification of C. trachomatis in a cohort of 219 HPV-infected Colombian females.C. trachomatis infection frequency was determined during each of the study's follow-up visits; it was detected by amplifying the cryptic plasmid sequence by polymerase chain reaction (PCR using two sets of primers: KL5/KL6 and KL1/KL2. Infection was defined as a positive PCR result using either set of primers at any time during the study. Cox proportional risk models were used for evaluating the association between the appearance of infection and a group of independent variables.Base line C. trachomatis infection frequency was 28% (n = 61. Most females infected by C. trachomatis were infected by multiple types of HPV (77.42%, greater prevalence occurring in females infected with HPV-16 (19.18%, followed by HPV-58 (17.81%. It was observed that females having had the most sexual partners (HR = 6.44: 1.59-26.05 95%CI or infection with multiple types of HPV (HR = 2.85: 1.22-6.63 95%CI had the greatest risk of developing C. trachomatis.The study provides data regarding the epidemiology of C. trachomatis /HPV coinfection in different population groups of Colombian females and contributes towards understanding the natural history of C. trachomatis infection.

  4. Frequency of Chlamydia trachomatis in genital specimens: kerman city, PCR method

    Directory of Open Access Journals (Sweden)

    Khalili M

    2008-06-01

    Full Text Available Background: Chlamydia trachomatis (CT is an obligate intracellular bacterium that causes genital disease and the most common sexually transmitted infection in the world. The most frequent risk factors associated with chlamydial infection are related to sexual behavior, multiple partners, and inconsistent condom use. Presenting primarily as urtheritis in men and cervicitis in women, CT a major cause of chronic pelvic inflammatory disease and subsequent infertility in women, eye and lung infection in newborns and other manifestations. Identification of CT-infected patients may prevent its spread and thereby reduce the high morbidity associated with CT infections. Polymerase chain reaction (PCR is a sensitive and specific method for the detection of small quantity of bacterial DNA in clinical samples. The aim of this study was to determine the frequency of C. trachomatis by PCR in genital samples from patients in the city of Kerman.Methods: A total of 130 genital samples including 64 endocervical and 66 urethral swab samples were collected by physicians. Nucleic acid was extracted from each sample using a commercial DNA extraction kit. PCR primers specific for a conserved region of the C. trachomatis omp2 gene, encoding an outer membrane protein, were used for amplification.  Results: A total of 9.2% (6.25% of cervicitis and 12.1% of urethritis of the samples were found positive for CT using this PCR method. Conclusions:  The present study shows a high prevalence of CT infection, especially in men with urethritis. Such patients should be referred to genitourinary clinics for treatment and partner notification. Given its worldwide prevalence, further CT studies on more populations are needed to assess potential public health implications of these infections.

  5. Chlamydia trachomatis co-opts the FGF2 signaling pathway to enhance infection.

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    Jung Hwa Kim

    2011-10-01

    Full Text Available The molecular details of Chlamydia trachomatis binding, entry, and spread are incompletely understood, but heparan sulfate proteoglycans (HSPGs play a role in the initial binding steps. As cell surface HSPGs facilitate the interactions of many growth factors with their receptors, we investigated the role of HSPG-dependent growth factors in C. trachomatis infection. Here, we report a novel finding that Fibroblast Growth Factor 2 (FGF2 is necessary and sufficient to enhance C. trachomatis binding to host cells in an HSPG-dependent manner. FGF2 binds directly to elementary bodies (EBs where it may function as a bridging molecule to facilitate interactions of EBs with the FGF receptor (FGFR on the cell surface. Upon EB binding, FGFR is activated locally and contributes to bacterial uptake into non-phagocytic cells. We further show that C. trachomatis infection stimulates fgf2 transcription and enhances production and release of FGF2 through a pathway that requires bacterial protein synthesis and activation of the Erk1/2 signaling pathway but that is independent of FGFR activation. Intracellular replication of the bacteria results in host proteosome-mediated degradation of the high molecular weight (HMW isoforms of FGF2 and increased amounts of the low molecular weight (LMW isoforms, which are released upon host cell death. Finally, we demonstrate the in vivo relevance of these findings by showing that conditioned medium from C. trachomatis infected cells is enriched for LMW FGF2, accounting for its ability to enhance C. trachomatis infectivity in additional rounds of infection. Together, these results demonstrate that C. trachomatis utilizes multiple mechanisms to co-opt the host cell FGF2 pathway to enhance bacterial infection and spread.

  6. Presence of Chlamydiales DNA in ticks and fleas suggests that ticks are carriers of Chlamydiae.

    Science.gov (United States)

    Croxatto, Antony; Rieille, Nadia; Kernif, Tahar; Bitam, Idir; Aeby, Sébastien; Péter, Olivier; Greub, Gilbert

    2014-06-01

    The Chlamydiales order includes the Chlamydiaceae, Parachlamydiaceae, Waddliaceae, Simkaniaceae, Criblamydiaceae, Rhabdochlamydiaceae, Clavichlamydiaceae, and Piscichlamydiaceae families. Members of the Chlamydiales order are obligate intracellular bacteria that replicate within eukaryotic cells of different origins including humans, animals, and amoebae. Many of these bacteria are pathogens or emerging pathogens of both humans and animals, but their true diversity is largely underestimated, and their ecology remains to be investigated. Considering their potential threat on human health, it is important to expand our knowledge on the diversity of Chlamydiae, but also to define the host range colonized by these bacteria. Thus, using a new pan-Chlamydiales PCR, we analyzed the prevalence of Chlamydiales DNA in ticks and fleas, which are important vectors of several viral and bacterial infectious diseases. To conduct this study, 1340 Ixodes ricinus ticks prepared in 192 pools were collected in Switzerland and 55 other ticks belonging to different tick species and 97 fleas belonging to different flea species were harvested in Algeria. In Switzerland, the prevalence of Chlamydiales DNA in the 192 pools was equal to 28.1% (54/192) which represents an estimated prevalence in the 1340 individual ticks of between 4.0% and 28.4%. The pan-Chlamydiales qPCR was positive for 45% (25/55) of tick samples collected in Algeria. The sequencing of the positive qPCR amplicons revealed a high diversity of Chlamydiales species. Most of them belonged to the Rhabdochlamydiaceae and Parachlamydiaceae families. Thus, ticks may carry Chlamydiales and should thus be considered as possible vectors for Chlamydiales propagation to both humans and animals.

  7. Chlamydia pneumoniae clinical isolate from gingival crevicular fluid: a potential atherogenic strain

    Directory of Open Access Journals (Sweden)

    Simone eFilardo

    2015-11-01

    Full Text Available Chlamydia pneumoniae has been associated to atherosclerotic cardiovascular diseases. The aim of our study was to characterize, for the first time, a C. pneumoniae strain isolated from the gingival crevicular fluid of a patient with chronic periodontitis, described as a risk factor for cardiovascular diseases. C. pneumoniae isolate was characterized and compared to the respiratory AR-39 strain by VD4-ompA genotyping and by investigating the intracellular growth in epithelial and macrophage cell lines and its ability to induce macrophage-derived foam cells. Inflammatory cytokine levels were determined in the gingival crevicular fluid sample.C. pneumoniae isolate showed a 99% similarity with the AR-39 strain in the VD4-ompA gene sequence and shared a comparable growth kinetic in epithelial cells and macrophages, as evidenced by the infectious progeny and by the number of chlamydial genomic copies. C. pneumoniae isolate significantly increased the number of foam cells as compared to uninfected and LDL-treated macrophages (45% vs 6%, P = 0.0065 and to the AR-39 strain (45% vs 30%, P = 0.0065. Significantly increased levels of interleukin 1-β (2.1±0.3 pg/μL and interleukin 6 (0.6±0.08 pg/μL were found.Our results suggest that C. pneumoniae may harbor inside oral cavity and potentially be atherogenic, even though further studies will be needed to clarify the involvement of C. pneumoniae in chronic periodontitis as a risk factor for cardiovascular diseases.

  8. Chlamydia trachomatis Frequency in a Cohort of HPV-Infected Colombian Women

    Science.gov (United States)

    Ramírez, Juan David; Soto-De León, Sara Cecilia; Camargo, Milena; Del Río-Ospina, Luisa; Sánchez, Ricardo; Patarroyo, Manuel Elkin; Patarroyo, Manuel Alfonso

    2016-01-01

    Background Chlamydia trachomatis (C. trachomatis), an obligate intracellular bacterium, is the commonest infectious bacterial agent of sexual transmission throughout the world. It has been shown that the presence of this bacteria in the cervix represents a risk regarding HPV persistence and, thereafter, in developing cervical cancer (CC). Prevalence rates may vary from 2% to 17% in asymptomatic females, depending on the population being analysed. This study reports the identification of C. trachomatis in a cohort of 219 HPV-infected Colombian females. Methods C. trachomatis infection frequency was determined during each of the study’s follow-up visits; it was detected by amplifying the cryptic plasmid sequence by polymerase chain reaction (PCR) using two sets of primers: KL5/KL6 and KL1/KL2. Infection was defined as a positive PCR result using either set of primers at any time during the study. Cox proportional risk models were used for evaluating the association between the appearance of infection and a group of independent variables. Results Base line C. trachomatis infection frequency was 28% (n = 61). Most females infected by C. trachomatis were infected by multiple types of HPV (77.42%), greater prevalence occurring in females infected with HPV-16 (19.18%), followed by HPV-58 (17.81%). It was observed that females having had the most sexual partners (HR = 6.44: 1.59–26.05 95%CI) or infection with multiple types of HPV (HR = 2.85: 1.22–6.63 95%CI) had the greatest risk of developing C. trachomatis. Conclusions The study provides data regarding the epidemiology of C. trachomatis /HPV coinfection in different population groups of Colombian females and contributes towards understanding the natural history of C. trachomatis infection. PMID:26807957

  9. Identification of Chlamydia pneumoniae within human choroidal neovascular membranes secondary to age-related macular degeneration.

    Science.gov (United States)

    Kalayoglu, Murat V; Bula, Deisy; Arroyo, Jorge; Gragoudas, Evangelos S; D'Amico, Donald; Miller, Joan W

    2005-11-01

    Age-related macular degeneration (AMD) is a leading cause of blindness in the United States, and increasing evidence suggests that it is an inflammatory disease. The prokaryotic obligate intracellular pathogen Chlamydia pneumoniae is emerging as a novel risk factor in cardiovascular disease, and recent sero-epidemiological data suggest that C. pneumoniae infection is also associated with AMD. In this study, we examined choroidal neovascular membrane (CNV) tissue from patients with neovascular AMD for the presence of C. pneumoniae and determined whether the pathogen can dysregulate the function of key cell types in ways that can cause neovascular AMD. Nine CNV removed from patients with neovascular AMD were examined for the presence of C. pneumoniae by immunohistochemistry (IHC) and polymerase chain reaction (PCR); in addition, we performed PCR on nine non-AMD eyes, and IHC on five non-AMD CNV, seven non-AMD eyes, and one internal limiting membrane specimen. Finally, human monocyte-derived macrophages and retinal pigment epithelial (RPE) cells were exposed to C. pneumoniae and assayed in vitro for the production of pro-angiogenic immunomodulators (VEGF, IL-8, and MCP-1). C. pneumoniae was detected in four of nine AMD CNV by IHC and two of nine AMD CNV by PCR, induced VEGF production by human macrophages, and increased production of IL-8 and MCP-1 by RPE cells. In contrast, none of the 22 non-AMD specimens showed evidence for C. pneumoniae. These data indicate that a pathogen capable of inducing chronic inflammation and pro-angiogenic cytokines can be detected in some AMD CNV, and suggest that infection may contribute to the pathogenesis of AMD.

  10. Concurrent sexual partners-A predictor of Chlamydia

    DEFF Research Database (Denmark)

    Jørgensen, Marianne Johansson; Olesen, Frede; Maindal, Helle Terkildsen

    2013-01-01

    Background:Chlamydia trachomatis is the most common sexually transmitted bacterial infection among young Danes and the spread is highly dependent on the population’s sexual behavior. Previous studies have found concurrent partnerships to be a possible predictor for C. trachomatis, but the signifi......Background:Chlamydia trachomatis is the most common sexually transmitted bacterial infection among young Danes and the spread is highly dependent on the population’s sexual behavior. Previous studies have found concurrent partnerships to be a possible predictor for C. trachomatis......, but the significance of this compared with other well-known predictors has only been briefly described. Aim: The aim is to examine if concurrent partners isan independent predictor for C. trachomatis infection in young Danes aged 15-29 years. Methods: Detailed sexual behavior data were collected via a web......-based questionnaire from 1000 randomly selected Danes (control group) and 1300 young Danes with a laboratory-verified C. trachomatis infection. All respondents were between 15 and 29 years. Using univariate analysis, we calculated the odds ratio (OR) for having had concurrent partners in the group of C. trachomatis...

  11. The prevalence of Chlamydia trachomatis infection in rural Thai women.

    Science.gov (United States)

    Thongkrajai, P; Thongkrajai, E; Pengsaa, P; Pakarasang, M

    1999-03-01

    A cross sectional study was designed to investigate the prevalence of Chlamydia trachomatis among different groups of rural women in the northeast Thailand. The presence of chlamydial antigens in endocervical swabs was detected by ELISA. The prevalences of Chlamydia trachomatis were 6.8% (31/485), 5.2% (24/466) and 6.7% (12/179) in women attending antenatal, postpartum and family planning clinics respectively. The average prevalences of C. trachomatis among hospital-based and community-based women were 6.1% (67/1,103) and 3.6% (15/411) respectively. In addition, the prevalences of some pathogens including Candida albicans, Trichomonas vaginalis, Treponema pallidum and Neisseria gonorrhoea among hospital-based and community-based women were 14.2, 2.8, 0.7, 0.2 and 10.9, 5.1, 2.7, 0.0% respectively. It was concluded that C. trachomatis was a problem of woman's reproductive health.

  12. Infertility after acute salpingitis with special reference to Chlamydia trachomatis.

    Science.gov (United States)

    Svensson, L; Mårdh, P A; Weström, L

    1983-09-01

    Of 552 women with laparoscopically verified acute salpingitis (AS), 299 were reviewed 2.5 to 7.5 years later. Cervical secretions from these women had been cultured for the presence of Chlamydia trachomatis and Neisseria gonorrhoeae. For 49 of 82 women with visually normal pelvic organs, such cultures were also performed; these women served as control subjects. In women exposing themselves to pregnancy, 50 (23.3%) of 197 AS patients and 2 (6.7%) of 30 control women were infertile for at least 1 year (P less than 0.02). After one episode of AS, women harboring chlamydiae, gonococci, both, or neither of these microorganisms in the cervix on admission seemed to have the same fertility prognosis. Infertility was correlated with the number of AS episodes, the erythrocyte sedimentation rate (millimeters per hour) at admission, and the severity of the inflammatory reactions of the tubes. The use of oral contraceptives at admission was found to be a positive prognostic factor regarding fertility. Oral contraceptives might protect the patient from severe tubal inflammatory reactions.

  13. Metallochaperones regulate intracellular copper levels.

    Directory of Open Access Journals (Sweden)

    W Lee Pang

    Full Text Available Copper (Cu is an important enzyme co-factor that is also extremely toxic at high intracellular concentrations, making active efflux mechanisms essential for preventing Cu accumulation. Here, we have investigated the mechanistic role of metallochaperones in regulating Cu efflux. We have constructed a computational model of Cu trafficking and efflux based on systems analysis of the Cu stress response of Halobacterium salinarum. We have validated several model predictions via assays of transcriptional dynamics and intracellular Cu levels, discovering a completely novel function for metallochaperones. We demonstrate that in addition to trafficking Cu ions, metallochaperones also function as buffers to modulate the transcriptional responsiveness and efficacy of Cu efflux. This buffering function of metallochaperones ultimately sets the upper limit for intracellular Cu levels and provides a mechanistic explanation for previously observed Cu metallochaperone mutation phenotypes.

  14. Detection of PCR inhibitors in cervical specimens by using the AMPLICOR Chlamydia trachomatis assay

    NARCIS (Netherlands)

    R.P.A.J. Verkooyen (Roel); A. Luijendijk (Ad); W.M. Huisman; W.H.F. Goessens (Wil); J.A.J.W. Kluytmans (Jan); J.H. van Rijsoort-Vos; H.A. Verbrugh (Henri)

    1996-01-01

    textabstractTo determine that susceptibility of AMPLICOR Chlamydia trachomatis PCR to inhibitory factors possibly present in cervical specimens, we obtained cervical specimens from 200 gynecology patients attending our outpatient clinic. The prevalence of C. trachomatis

  15. High Titers of Chlamydia trachomatis Antibodies in Brazilian Women with Tubal Occlusion or Previous Ectopic Pregnancy

    Directory of Open Access Journals (Sweden)

    A. C. S. Machado

    2007-01-01

    Full Text Available Objective. To evaluate serum chlamydia antibody titers (CATs in tubal occlusion or previous ectopic pregnancy and the associated risk factors. Methods. The study population consisted of 55 women wih tubal damage and 55 parous women. CAT was measured using the whole-cell inclusion immunofluorescence test and cervical chlamydial DNA detected by PCR. Odds ratios were calculated to assess variables associated with C. trachomatis infection. Results. The prevalence of chlamydial antibodies and antibody titers in women with tubal occlusion or previous ectopic pregnancy was significantly higher (P<.01 than in parous women. Stepwise logistic regression analysis showed that chlamydia IgG antibodies were associated with tubal damage and with a larger number of lifetime sexual partners. Conclusions. Chlamydia antibody titers were associated with tubal occlusion, prior ectopic pregnancy, and with sexual behavior, suggesting that a chlamydia infection was the major contributor to the tubal damage in these women.

  16. Causality of Chlamydiae in Arthritis and Spondyloarthritis: a Plea for Increased Translational Research.

    Science.gov (United States)

    Zeidler, Henning; Hudson, Alan P

    2016-02-01

    Current molecular genetic understanding of the metabolically active persistent infection state of Chlamydia trachomatis and Chlamydia pneumoniae in the synovium in patients with arthritis and spondyloarthritis favors a causal relationship. Here, we examine how adequately the accepted criteria for that etiologic relationship are fulfilled, emphasizing the situation in which these microorganisms cannot be cultivated by standard or other means. We suggest that this unusual situation of causality by chlamydiae in rheumatic disease requires establishment of a consensus regarding microorganism-specific terminology as well as the development of new diagnostic and classification criteria. Recent studies demonstrate the value of molecular testing for diagnosis of reactive arthritis, undifferentiated spondyloarthritis, and undifferentiated arthritis caused by C. trachomatis and C. pneumoniae in clinical practice. Data regarding combination antibiotic therapy is consistent with the causative role of chlamydiae for these diseases. Observations of multiple intra-articular coinfections require more research to understand the implications and to respond to them.

  17. Evaluation of PCR, culture, and serology for diagnosis of Chlamydia pneumoniae respiratory infections

    NARCIS (Netherlands)

    R.P.A.J. Verkooyen (Roel); D. Willemse; S.C. Hiep-van Casteren; S.A. Joulandan; R.J. Snijder; H.P. van Helden; M.F. Peeters; H.A. Verbrugh (Henri); J.M. van den Bosch (Jules)

    1998-01-01

    textabstractWe prospectively studied 156 patients with a diagnosis of community-acquired pneumonia requiring admission. Several respiratory specimens were obtained for the detection of Chlamydia pneumoniae by cell culture and PCR. Three serum samples were obtained from

  18. Exploring anti-bacterial compounds against intracellular Legionella.

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    Christopher F Harrison

    Full Text Available Legionella pneumophila is a ubiquitous fresh-water bacterium which reproduces within its erstwhile predators, environmental amoeba, by subverting the normal pathway of phagocytosis and degradation. The molecular mechanisms which confer resistance to amoeba are apparently conserved and also allow replication within macrophages. Thus, L. pneumophila can act as an 'accidental' human pathogen and cause a severe pneumonia known as Legionnaires' disease. The intracellular localisation of L. pneumophila protects it from some antibiotics, and this fact must be taken into account to develop new anti-bacterial compounds. In addition, the intracellular lifestyle of L. pneumophila may render the bacteria susceptible to compounds diminishing bacterial virulence and decreasing intracellular survival and replication of this pathogen. The development of a single infection cycle intracellular replication assay using GFP-producing L. pneumophila and Acanthamoebacastellanii amoeba is reported here. This fluorescence-based assay allows for continuous monitoring of intracellular replication rates, revealing the effect of bacterial gene deletions or drug treatment. To examine how perturbations of the host cell affect L. pneumophila replication, several known host-targeting compounds were tested, including modulators of cytoskeletal dynamics, vesicle scission and Ras GTPase localisation. Our results reveal a hitherto unrealized potential antibiotic property of the β-lactone-based Ras depalmitoylation inhibitor palmostatin M, but not the closely related inhibitor palmostatin B. Further characterisation indicated that this compound caused specific growth inhibition of Legionella and Mycobacterium species, suggesting that it may act on a common bacterial target.

  19. Genital chlamydia trachomatis infection among female undergraduate students of University of Port Harcourt, Nigeria

    OpenAIRE

    A Ugboma Henry Arinze; Nwagwu Victor Onyebuchi; Jeremiah Isreal

    2014-01-01

    Background: Genital Chlamydia trachomatis infection is a common bacterial sexually transmitted infection worldwide. There is little information about this infection in Nigeria. This study determined the prevalence of genital Chlamydia trachomatis infection among female undergraduates of University of Port Harcourt and identify the various associated risk factors. Materials and Methods: A cross-sectional prospective study of 354 female students was done. Their socio-demographic characteristics...

  20. Intracellular Signals of T Cell Costimulation

    Institute of Scientific and Technical Information of China (English)

    Jianxun Song; Fengyang Tylan Lei; Xiaofang Xiong; Rizwanul Haque

    2008-01-01

    Ligation of T cell receptor (TCR) alone is insufficient to induce full activation of T lymphocytes. Additional ligand-receptor interactions (costimulation) on antigen presenting cells (APCs) and T cells are required. T cell costimulation has been shown to be essential for eliciting efficient T cell responses, involving all phases during T cell development. However, the mechanisms by which costimulation affects the function of T cells still need to be elucidated. In recent years, advances have been made in studies of costimulation as potential therapies in cancer, infectious disease as well as autoimmune disease. In this review, we discussed intracellular costimulation signals that regulate T cell proliferation, cell cycle progression, cytokine production, survival, and memory development. In general, the pathway of phosphoinositide-3 kinase (PBK)/protein kinase B (PKB, also known as Akt)/nuclear factor κB (NF-κB) might be central to many costimulatory effects. Through these pathways, costimulation controls T-cell expansion and proliferation by maintenance of survivin and aurora B expression, and sustains long-term T-cell survival and memory development by regulating the expression of bci-2 family members. Cellular & Molecular Immunology.2008;5(4):239-247.

  1. Mixed infections with Chlamydia and porcine epidemic diarrhea virus - a new in vitro model of chlamydial persistence

    Directory of Open Access Journals (Sweden)

    Kaiser Carmen

    2010-07-01

    Full Text Available Abstract Background Chlamydiae induce persistent infections, which have been associated with a wide range of chronic diseases in humans and animals. Mixed infections with Chlamydia and porcine epidemic diarrhea virus (PEDV may result in generation of persistent chlamydial infections. To test this hypothesis, an in vitro model of dual infection with cell culture-adapted PEDV and Chlamydia abortus or Chlamydia pecorum in Vero cells was established. Results Infected cultures were investigated by immunofluorescence (IF, transmission electron microscopy (TEM and re-infection experiments. By IF, Chlamydia-infected cells showed normal inclusions after 39 hpi. Dual infections with Chlamydia abortus revealed a heterogenous mix of inclusion types including small inclusions consisting of aberrant bodies (ABs, medium-sized inclusions consisting of ABs and reticulate bodies and normal inclusions. Only aberrant inclusions were observable in dual infection experiments with Chlamydia pecorum and PEDV. TEM examinations of mixed infections with Chlamydia abortus and Chlamydia pecorum revealed aberrant chlamydial inclusions containing reticulate-like, pleomorphic ABs, which were up to 2 μm in diameter. No re-differentiation into elementary bodies (EBs was detected. In re-infection experiments, co-infected cells produced fewer EBs than monoinfected cells. Conclusions In the present study we confirm that PEDV co-infection alters the developmental cycle of member species of the family Chlamydiaceae, in a similar manner to other well-described persistence induction methods. Interestingly, this effect appears to be partially species-specific as Chlamydia pecorum appears more sensitive to PEDV co-infection than Chlamydia abortus, as evidenced by TEM and IF observations of a homogenous population of aberrant inclusions in PEDV - Chlamydia pecorum co-infections.

  2. The prevalence of Chlamydia trachomatis infection in Australia: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Lewis Dyani

    2012-05-01

    Full Text Available Abstract Background Chlamydia trachomatis is a common sexually transmitted infection in Australia. This report aims to measure the burden of chlamydia infection by systematically reviewing reports on prevalence in Australian populations. Methods Electronic databases and conference websites were searched from 1997–2011 using the terms ‘Chlamydia trachomatis’ OR ‘chlamydia’ AND ‘prevalence’ OR ‘epidemiology’ AND ‘Australia’. Reference lists were checked and researchers contacted for additional literature. Studies were categorised by setting and participants, and meta-analysis conducted to determine pooled prevalence estimates for each category. Results Seventy-six studies met the inclusion criteria for the review. There was a high level of heterogeneity between studies; however, there was a trend towards higher chlamydia prevalence in younger populations, Indigenous Australians, and those attending sexual health centres. In community or general practice settings, pooled prevalence for women Conclusions Chlamydia trachomatis infections are a significant health burden in Australia; however, accurate estimation of chlamydia prevalence in Australian sub-populations is limited by heterogeneity within surveyed populations, and variations in sampling methodologies and data reporting. There is a need for more large, population-based studies and prospective cohort studies to compliment mandatory notification data.

  3. Survival Analysis

    CERN Document Server

    Miller, Rupert G

    2011-01-01

    A concise summary of the statistical methods used in the analysis of survival data with censoring. Emphasizes recently developed nonparametric techniques. Outlines methods in detail and illustrates them with actual data. Discusses the theory behind each method. Includes numerous worked problems and numerical exercises.

  4. [A child with iritis due to Chlamydia pneumoniae infection].

    Science.gov (United States)

    Yamada, S; Tsumura, N; Nagai, K; Yamada, T; Sakata, Y; Tominaga, K; Kato, H; Motohiro, T; Masunaga, N; Mochizuki, M

    1994-12-01

    A case of uncommon iritis due to Chlamydia pneumoniae (C. pneumoniae) is reported. The patient was a 9-year-old boy who had suffered from cough, pharyngeal pain, and low grade fever. The symptoms persisted for more than 1 month in spite of an oral cephem antibiotic. Ophthalmalgia, congestion around the iris and cough had lasted with alleviation and exacerbation. A diagnosis of C. pneumoniae infection was made by specific polymerase chain reaction (PCR) method and microimmunofluorescence test (MIF). The symptoms subsided with administration of clarithromycin (CAM: 300 mg/day) for 2 weeks. Because of the simultaneous alleviation of iritis, C. pneumoniae infection was considered to introduce the iritis. Much remains to be clarified about this pathogenesis of iritis and more detailed evaluations are required.

  5. Quinolones for the Treatment of Neisseria Gonorrhoeae and Chlamydia Trachomatis

    Directory of Open Access Journals (Sweden)

    Sebastian Faro

    1993-01-01

    Full Text Available The most commonly sexually transmitted bacteria are Neisseria gonorrhoeae and Chlamydia trachomatis. The quinolones ofloxacin and ciprofloxacin have been shown to have activity against both of these bacteria in vitro and in vivo. Ofloxacin is particularly well suited for the treatment of N. gonorrhoeae and C. trachomatis cervical infection, which can be considered the earliest manifestation of pelvic inflammatory disease (PID. Not only can ofloxacin be effectively used as a single agent, it is also useful in treating urinary tract infections caused by Enterobacteriaceae. Although it has moderate activity against anaerobes in general, ofloxacin does have activity against the anaerobes commonly isolated from female patients with soft tissue pelvic infections. Thus, ofloxacin has the potential for being utilized to treat early salpingitis.

  6. Chlamydia trachomatis causing neonatal conjunctivitis in a tertiary care center

    Directory of Open Access Journals (Sweden)

    Kakar S

    2010-01-01

    Full Text Available Chlamydia trachomatis is considered a major aetiological agent of conjunctivitis in newborns. The objective of the present study was to determine the aetiology of neonatal conjunctivitis and clinico-epidemiological correlates of chlamydial ophthalmia neonatorum. Fifty-eight newborns with signs and symptoms of conjunctivitis were studied. Conjunctival specimens were subjected to Gram staining, routine bacteriological culture, culture for Neisseria gonorrhoeae and direct fluorescent antibody (DFA staining for diagnosis of C. trachomatis infection. C. trachomatis was detected in 18 (31% neonates. Findings suggest that since C. trachomatis is the most common cause of neonatal conjunctivitis, routine screening and treatment of genital C. trachomatis infection in pregnant women and early diagnosis and treatment of neonatal Chlamydial conjunctivitis may be considered for its prevention and control.

  7. Chlamydia pneumoniae respiratory infection after allogeneic stem cell transplantation.

    Science.gov (United States)

    Geisler, William M; Corey, Lawrence

    2002-03-27

    Chlamydia pneumoniae is a common cause of upper and lower respiratory tract infections in immunocompetent patients; however, its role as a respiratory pathogen in immunocompromised hosts has been infrequently recognized. We describe C. pneumoniae lower respiratory tract infection in a 19-year-old male after allogeneic stem cell transplantation. The patient developed fever on day +14, and a subsequent computed tomography scan of the chest revealed a right lateral pleural-based opacity, which was then resected during thoracoscopy. Diagnosis was made by culture and staining of the resected tissue with C. pneumoniae-specific monoclonal antibodies, and azithromycin was administered. To the best of our knowledge, this is the first report of C. pneumoniae respiratory infection after stem cell or marrow transplantation. C. pneumoniae often coexists with other etiologic agents of pneumonia in immunocompromised patients. Considering the infrequency of infections from this organism in this clinical setting, one must still rule out other more likely respiratory pathogens.

  8. Cloning of Omp1 Gene from Chlamydia trachomatis F Genotype

    Institute of Scientific and Technical Information of China (English)

    QI Manli(齐蔓莉); LIU Quanzhong(刘全中); JIAO Wenling(缴稳苓); TIAN Jingqun(田敬群); CHEN Jinying(陈锦英)

    2002-01-01

    Objectives: To directionally clone the omp1 gene fromChlamydia trachomatis (Ct) F genotype onto a plasmid vectorfor constructing a rudimentary DNA vaccine.Methods: The complete omp1 gene from genomic DNA of CtF genotype wild species was amplified with primers designedby computer. The recombinant gene was obtained byrestriction enzyme cutting, linking the gene with the plasmidvector in vitro, transforming the recombinant gene intobacteria, and extracting the DNA from the bacteria.Results: DNA extracted from the bacteria was composed ofthe omp1 gene and plasmid, which is identified by threemethods of singular restrictive enzyme cutting, doublerestrictive enzyme cutting and PCR.Conclusion: Cloning of the omp1 gene from the Ct Fgenotype means that a rudimentary DNA vaccine wassuccessfully constructed.

  9. Sensitivity of Francisella tularensis to ultrapure water and deoxycholate: implications for bacterial intracellular growth assay in macrophages

    Science.gov (United States)

    Chalabaev, Sabina; Anderson, Christine A.; Onderdonk, Andrew B.; Kasper, Dennis L.

    2011-01-01

    The ability of Francisella tularensis to replicate in macrophages is critical for its pathogenesis, therefore intracellular growth assays are important tools for assessing virulence. We show that two lysis solutions commonly used in these assays, deionized water and deoxycholate in PBS, lead to highly inaccurate measurements of intracellular bacterial survival. PMID:21420447

  10. Monitoring county-level chlamydia incidence in Texas, 2004 – 2005: application of empirical Bayesian smoothing and Exploratory Spatial Data Analysis (ESDA) methods

    OpenAIRE

    Owens Chantelle J; Owusu-Edusei Kwame

    2009-01-01

    Abstract Background Chlamydia continues to be the most prevalent disease in the United States. Effective spatial monitoring of chlamydia incidence is important for successful implementation of control and prevention programs. The objective of this study is to apply Bayesian smoothing and exploratory spatial data analysis (ESDA) methods to monitor Texas county-level chlamydia incidence rates by examining spatiotemporal patterns. We used county-level data on chlamydia incidence (for all ages, g...

  11. Chlamydia trachomatis growth and development requires the activity of host Long-chain Acyl-CoA Synthetases (ACSLs).

    Science.gov (United States)

    Recuero-Checa, Maria A; Sharma, Manu; Lau, Constance; Watkins, Paul A; Gaydos, Charlotte A; Dean, Deborah

    2016-03-18

    The obligate-intracellular pathogen Chlamydia trachomatis (Ct) has undergone considerable genome reduction with consequent dependence on host biosynthetic pathways, metabolites and enzymes. Long-chain acyl-CoA synthetases (ACSLs) are key host-cell enzymes that convert fatty acids (FA) into acyl-CoA for use in metabolic pathways. Here, we show that the complete host ACSL family [ACSL1 and ACSL3-6] translocates into the Ct membrane-bound vacuole, termed inclusion, and remains associated with membranes of metabolically active forms of Ct throughout development. We discovered that three different pharmacologic inhibitors of ACSL activity independently impede Ct growth in a dose-dependent fashion. Using an FA competition assay, host ACSLs were found to activate Ct branched-chain FAs, suggesting that one function of the ACSLs is to activate Ct FAs and host FAs (recruited from the cytoplasm) within the inclusion. Because the ACSL inhibitors can deplete lipid droplets (LD), we used a cell line where LD synthesis was switched off to evaluate whether LD deficiency affects Ct growth. In these cells, we found no effect on growth or on translocation of ACSLs into the inclusion. Our findings support an essential role for ACSL activation of host-cell and bacterial FAs within the inclusion to promote Ct growth and development, independent of LDs.

  12. Anorectal Chlamydia trachomatis Load Is Similar in Men Who Have Sex with Men and Women Reporting Anal Sex.

    Directory of Open Access Journals (Sweden)

    Geneviève A F S van Liere

    Full Text Available Anorectal Chlamydia trachomatis (chlamydia is frequently diagnosed in men who have sex with men (MSM and in women, but it is unknown whether these infections are comparable in clinical impact and transmission potential. Quantifying bacterial load and identifying determinants associated with high bacterial load could provide more insight.We selected a convenience sample of MSM who reported anal sex (n = 90 and women with concurrent urogenital/anorectal chlamydia who reported anal sex (n = 51 or did not report anal sex (n = 61 from the South Limburg Public Health Service's STI unit. Bacterial load (Chlamydia/ml was quantified for all samples and log transformed for analyses. Samples with an unquantifiable human leukocyte antigen (n = 9 were excluded from analyses, as they were deemed inadequately sampled.The mean log anorectal chlamydia load (3.50 was similar for MSM and women who reported having anal sex (3.80, P = 0.21. The anorectal chlamydia load was significantly higher in these groups than in women who did not report having anal sex (2.76, P = 0.001. Detectable load values ranged from 1.81-6.32 chlamydia/ml for MSM, 1.74-7.33 chlamydia/ml for women who reported having anal sex and 1.84-6.31 chlamydia/ml for women who did not report having anal sex. Symptoms and several other determinants were not associated with anorectal chlamydia load.Women who did not report anal sex had lower anorectal loads, but they were within a similar range to the other two groups. Anorectal chlamydia load was comparable between MSM and women who reported anal sex, suggesting similar transmission potential.

  13. Comparison of subcutaneous versus intranasal immunization of male koalas (Phascolarctos cinereus) for induction of mucosal and systemic immunity against Chlamydia pecorum.

    Science.gov (United States)

    Waugh, Courtney A; Timms, Peter; Andrew, Dean; Rawlinson, Galit; Brumm, Jacqui; Nilsson, Karen; Beagley, Kenneth W

    2015-02-11

    Chlamydia pecorum infections are debilitating in the koala, contributing significantly to morbidity and mortality, with current antibiotic treatments having minimal success and adversely affecting gut microflora. This, combined with the sometimes-asymptomatic nature of the infection, suggests that an efficacious anti-chlamydial vaccine is required to control chlamydial infections in the koala. To date vaccination studies have focused primarily on female koalas, however, given the physiological differences between male and female reproductive tracts, we tested the efficacy of a vaccine in 12 captive male koalas. We evaluated the potential of both subcutaneous and intranasal vaccine delivery to elicit mucosal immunity in male koalas. Our results showed that both intranasal and subcutaneous delivery of a vaccine consisting of C. pecorum major outer membrane protein (MOMP) and the adjuvant immunostimulating complex (ISC) induced significant immune responses in male koalas. Subcutaneous immunization elicited stronger cell-mediated responses in peripheral blood lymphocytes (PBL), and greater plasma antibody levels whereas the intranasal immunization elicited stronger humoral responses in urogenital tract (UGT) secretions. This is the first time a Chlamydia vaccine has been tested in the male koala and the first assessment of a mucosal vaccination route in this species. Our results suggest that vaccination of male koalas can elicit mucosal immunity and could contribute to the long-term survivability of wild populations of the koala.

  14. Chlamydia trachomatis Antibody Testing in Vaginal Mucosal Material versus Blood Samples of Women Attending a Fertility Clinic and an STI Clinic

    NARCIS (Netherlands)

    van den Broek, Ingrid V F; Land, Jolande A; van Bergen, Jan E A M; Morré, Servaas A; van der Sande, Marianne A B

    2014-01-01

    Background. Chlamydia infections often follow an asymptomatic course but may damage the reproductive tract. Chlamydia antibodies in serum are used as markers for past infections and can relate to tubal pathology and infertility. This "proof of principle" study aimed to assess whether Chlamydia antib

  15. Evaluation of Clearview and Magic Lite tests, polymerase chain reaction, and cell culture for detection of Chlamydia trachomatis in urogenital specimens

    NARCIS (Netherlands)

    Kluytmans, J A; Goessens, W H; Mouton, J W; van Rijsoort-Vos, J H; Niesters, H G; Quint, W G; Habbema, L; Stolz, E; Wagenvoort, J H

    1993-01-01

    The Clearview Chlamydia test (CV; Unipath Ltd., Bedford, United Kingdom), the Magic Lite Chlamydia test (ML; CIBA Corning, Medfield, Mass.), a polymerase chain reaction (PCR), and cell culture (CC) were evaluated for detection of Chlamydia trachomatis in urogenital specimens. Specimens were collecte

  16. Extragenital Infections Caused by Chlamydia trachomatis and Neisseria gonorrhoeae: A Review of the Literature.

    Science.gov (United States)

    Chan, Philip A; Robinette, Ashley; Montgomery, Madeline; Almonte, Alexi; Cu-Uvin, Susan; Lonks, John R; Chapin, Kimberle C; Kojic, Erna M; Hardy, Erica J

    2016-01-01

    In the United States, sexually transmitted diseases due to Chlamydia trachomatis and Neisseria gonorrhoeae continue to be a major public health burden. Screening of extragenital sites including the oropharynx and rectum is an emerging practice based on recent studies highlighting the prevalence of infection at these sites. We reviewed studies reporting the prevalence of extragenital infections in women, men who have sex with men (MSM), and men who have sex only with women (MSW), including distribution by anatomical site. Among women, prevalence was found to be 0.6-35.8% for rectal gonorrhea (median reported prevalence 1.9%), 0-29.6% for pharyngeal gonorrhea (median 2.1%), 2.0-77.3% for rectal chlamydia (median 8.7%), and 0.2-3.2% for pharyngeal chlamydia (median 1.7%). Among MSM, prevalence was found to be 0.2-24.0% for rectal gonorrhea (median 5.9%), 0.5-16.5% for pharyngeal gonorrhea (median 4.6%), 2.1-23.0% for rectal chlamydia (median 8.9%), and 0-3.6% for pharyngeal chlamydia (median 1.7%). Among MSW, the prevalence was found to be 0-5.7% for rectal gonorrhea (median 3.4%), 0.4-15.5% for pharyngeal gonorrhea (median 2.2%), 0-11.8% for rectal chlamydia (median 7.7%), and 0-22.0% for pharyngeal chlamydia (median 1.6%). Extragenital infections are often asymptomatic and found in the absence of reported risk behaviors, such as receptive anal and oral intercourse. We discuss current clinical recommendations and future directions for research.

  17. Extragenital Infections Caused by Chlamydia trachomatis and Neisseria gonorrhoeae: A Review of the Literature

    Directory of Open Access Journals (Sweden)

    Philip A. Chan

    2016-01-01

    Full Text Available In the United States, sexually transmitted diseases due to Chlamydia trachomatis and Neisseria gonorrhoeae continue to be a major public health burden. Screening of extragenital sites including the oropharynx and rectum is an emerging practice based on recent studies highlighting the prevalence of infection at these sites. We reviewed studies reporting the prevalence of extragenital infections in women, men who have sex with men (MSM, and men who have sex only with women (MSW, including distribution by anatomical site. Among women, prevalence was found to be 0.6–35.8% for rectal gonorrhea (median reported prevalence 1.9%, 0–29.6% for pharyngeal gonorrhea (median 2.1%, 2.0–77.3% for rectal chlamydia (median 8.7%, and 0.2–3.2% for pharyngeal chlamydia (median 1.7%. Among MSM, prevalence was found to be 0.2–24.0% for rectal gonorrhea (median 5.9%, 0.5–16.5% for pharyngeal gonorrhea (median 4.6%, 2.1–23.0% for rectal chlamydia (median 8.9%, and 0–3.6% for pharyngeal chlamydia (median 1.7%. Among MSW, the prevalence was found to be 0–5.7% for rectal gonorrhea (median 3.4%, 0.4–15.5% for pharyngeal gonorrhea (median 2.2%, 0–11.8% for rectal chlamydia (median 7.7%, and 0–22.0% for pharyngeal chlamydia (median 1.6%. Extragenital infections are often asymptomatic and found in the absence of reported risk behaviors, such as receptive anal and oral intercourse. We discuss current clinical recommendations and future directions for research.

  18. Chlamydia trachomatis incidence and re-infection among young women--behavioural and microbiological characteristics.

    Directory of Open Access Journals (Sweden)

    Jennifer Walker

    Full Text Available BACKGROUND: This study aimed to estimate rates of chlamydia incidence and re-infection and to investigate the dynamics of chlamydia organism load in prevalent, incident and re-infections among young Australian women. METHODS: 1,116 women aged 16 to 25 years were recruited from primary care clinics in Australia. Vaginal swabs were collected at 3 to 6 month intervals for chlamydia testing. Chlamydia organism load was measured by quantitative PCR. RESULTS: There were 47 incident cases of chlamydia diagnosed and 1,056.34 person years of follow up with a rate of 4.4 per 100 person years (95% CI: 3.3, 5.9. Incident infection was associated with being aged 16 to 20 years [RR = 3.7 (95%CI: 1.9, 7.1], being employed [RR = 2.4 (95%CI: 1.1, 4.9] and having two or more new sex partners [RR = 5.5 (95%CI: 2.6, 11.7]. Recent antibiotic use was associated with a reduced incidence [RR:0.1 (95%CI: 0.0, 0.5]. There were 14 re-infections with a rate of 22.3 per 100 person years (95%CI: 13.2, 37.6. The median time to re-infection was 4.6 months. Organism load was higher for prevalent than incident infections (p<0.01 and for prevalent than re-infections (p<0.01. CONCLUSIONS: Chlamydia is common among young women and a high proportion of women are re-infected within a short period of time, highlighting the need for effective partner treatment and repeat testing. The difference in organism load between prevalent and incident infections suggests prevalent infection may be more important for ongoing transmission of chlamydia.

  19. Defining species-specific immunodominant B cell epitopes for molecular serology of Chlamydia species.

    Science.gov (United States)

    Rahman, K Shamsur; Chowdhury, Erfan U; Poudel, Anil; Ruettger, Anke; Sachse, Konrad; Kaltenboeck, Bernhard

    2015-05-01

    Urgently needed species-specific enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies against Chlamydia spp. have been elusive due to high cross-reactivity of chlamydial antigens. To identify Chlamydia species-specific B cell epitopes for such assays, we ranked the potential epitopes of immunodominant chlamydial proteins that are polymorphic among all Chlamydia species. High-scoring peptides were synthesized with N-terminal biotin, followed by a serine-glycine-serine-glycine spacer, immobilized onto streptavidin-coated microtiter plates, and tested with mono-specific mouse hyperimmune sera against each Chlamydia species in chemiluminescent ELISAs. For each of nine Chlamydia species, three to nine dominant polymorphic B cell epitope regions were identified on OmpA, CT618, PmpD, IncA, CT529, CT442, IncG, Omp2, TarP, and IncE proteins. Peptides corresponding to 16- to 40-amino-acid species-specific sequences of these epitopes reacted highly and with absolute specificity with homologous, but not heterologous, Chlamydia monospecies-specific sera. Host-independent reactivity of such epitopes was confirmed by testing of six C. pecorum-specific peptides from five proteins with C. pecorum-reactive sera from cattle, the natural host of C. pecorum. The probability of cross-reactivity of peptide antigens from closely related chlamydial species or strains correlated with percent sequence identity and declined to zero at Chlamydia spp. We anticipate that these peptide antigens will improve chlamydial serology by providing easily accessible assays to nonspecialist laboratories. Our approach also lends itself to the identification of relevant epitopes of other microbial pathogens.

  20. Stochastic models of intracellular transport

    KAUST Repository

    Bressloff, Paul C.

    2013-01-09

    The interior of a living cell is a crowded, heterogenuous, fluctuating environment. Hence, a major challenge in modeling intracellular transport is to analyze stochastic processes within complex environments. Broadly speaking, there are two basic mechanisms for intracellular transport: passive diffusion and motor-driven active transport. Diffusive transport can be formulated in terms of the motion of an overdamped Brownian particle. On the other hand, active transport requires chemical energy, usually in the form of adenosine triphosphate hydrolysis, and can be direction specific, allowing biomolecules to be transported long distances; this is particularly important in neurons due to their complex geometry. In this review a wide range of analytical methods and models of intracellular transport is presented. In the case of diffusive transport, narrow escape problems, diffusion to a small target, confined and single-file diffusion, homogenization theory, and fractional diffusion are considered. In the case of active transport, Brownian ratchets, random walk models, exclusion processes, random intermittent search processes, quasi-steady-state reduction methods, and mean-field approximations are considered. Applications include receptor trafficking, axonal transport, membrane diffusion, nuclear transport, protein-DNA interactions, virus trafficking, and the self-organization of subcellular structures. © 2013 American Physical Society.

  1. A bioinformatic approach to understanding antibiotic resistance in intracellular bacteria through whole genome analysis

    OpenAIRE

    Biswas, S.(National Institute of Science Education and Research, Bhubaneswar, India); Raoult, Didier; Rolain, J. M.

    2008-01-01

    Intracellular bacteria survive within eukaryotic host cells and are difficult to kill with certain antibiotics. As a result, antibiotic resistance in intracellular bacteria is becoming commonplace in healthcare institutions. Owing to the lack of methods available for transforming these bacteria, we evaluated the mechanisms of resistance using molecular methods and in silico genome analysis. The objective of this review was to understand the molecular mechanisms of antibiotic resistance throug...

  2. Eradication of intracellular Francisella tularensis in THP-1 human macrophages with a novel autophagy inducing agent

    Directory of Open Access Journals (Sweden)

    Gunn John S

    2009-12-01

    Full Text Available Abstract Background Autophagy has been shown recently to play an important role in the intracellular survival of several pathogenic bacteria. In this study, we investigated the effect of a novel small-molecule autophagy-inducing agent, AR-12, on the survival of Francisella tularensis, the causative bacterium of tularemia in humans and a potential bioterrorism agent, in macrophages. Methods and results Our results show that AR-12 induces autophagy in THP-1 macrophages, as indicated by increased autophagosome formation, and potently inhibits the intracellular survival of F. tularensis (type A strain, Schu S4 and F. novicida in macrophages in association with increased bacterial co-localization with autophagosomes. The effect of AR-12 on intracellular F. novicida was fully reversed in the presence of the autophagy inhibitor, 3-methyl adenine or the lysosome inhibitor, chloroquine. Intracellular F. novicida were not susceptible to the inhibitory activity of AR-12 added at 12 h post-infection in THP-1 macrophages, and this lack of susceptibility was independent of the intracellular location of bacteria. Conclusion Together, AR-12 represents a proof-of-principle that intracellular F. tularensis can be eradicated by small-molecule agents that target innate immunity.

  3. Chlamydia trachomatis Pgp3 Antibody Population Seroprevalence before and during an Era of Widespread Opportunistic Chlamydia Screening in England (1994-2012)

    Science.gov (United States)

    Horner, Patrick J.; Craig, Rachel; Mindell, Jennifer S.; Murphy, Gary; McClure, Myra O.; Soldan, Kate; Nardone, Anthony; Johnson, Anne M.

    2017-01-01

    Background Opportunistic chlamydia screening of <25 year-olds was nationally-implemented in England in 2008 but its impact on chlamydia transmission is poorly understood. We undertook a population-based seroprevalence study to explore the impact of screening on cumulative incidence of chlamydia, as measured by C.trachomatis-specific antibody. Methods Anonymised sera from participants in the nationally-representative Health Surveys for England (HSE) were tested for C.trachomatis antibodies using two novel Pgp3 enzyme-linked immunosorbent assays (ELISAs) as a marker of past infection. Determinants of being seropositive were explored using logistic regression among 16–44 year-old women and men in 2010 and 2012 (years when sexual behaviour questions were included in the survey) (n = 1,402 women; 1,119 men). Seroprevalence trends among 16–24 year-old women (n = 3,361) were investigated over ten time points from 1994–2012. Results In HSE2010/2012, Pgp3 seroprevalence among 16–44 year-olds was 24.4% (95%CI 22.0–27.1) in women and 13.9% (11.8–16.2) in men. Seroprevalence increased with age (up to 33.5% [27.5–40.2] in 30–34 year-old women, 18.7% [13.4–25.6] in 35–39 year-old men); years since first sex; number of lifetime sexual partners; and younger age at first sex. 76.7% of seropositive 16–24 year-olds had never been diagnosed with chlamydia. Among 16–24 year-old women, a non-significant decline in seroprevalence was observed from 2008–2012 (prevalence ratio per year: 0.94 [0.84–1.05]). Conclusion Our application of Pgp3 ELISAs demonstrates a high lifetime risk of chlamydia infection among women and a large proportion of undiagnosed infections. A decrease in age-specific cumulative incidence following national implementation of opportunistic chlamydia screening has not yet been demonstrated. We propose these assays be used to assess impact of chlamydia control programmes. PMID:28129328

  4. Surviving Objects

    OpenAIRE

    Murjas, Teresa

    2012-01-01

    Surviving Objects (2012) is a devised multi-media practice-as-research performance based on extensive interviews conducted with my elderly mother and recorded on a hand-held device. Our conversations concern her experiences as a child refugee following violent deportation by the Soviet Army from Eastern Poland to Siberia (1941), and her subsequent route, via Persia, to a British-run refugee camp in Northern Rhodesia, where she remained for 6 years before arriving in the UK. In order to aid my...

  5. Deciphering the Intracellular Fate of Propionibacterium acnes in Macrophages

    Directory of Open Access Journals (Sweden)

    Natalie Fischer

    2013-01-01

    Full Text Available Propionibacterium acnes is a Gram-positive bacterium that colonizes various niches of the human body, particularly the sebaceous follicles of the skin. Over the last years a role of this common skin bacterium as an opportunistic pathogen has been explored. Persistence of P. acnes in host tissue has been associated with chronic inflammation and disease development, for example, in prostate pathologies. This study investigated the intracellular fate of P. acnes in macrophages after phagocytosis. In a mouse model of P. acnes-induced chronic prostatic inflammation, the bacterium could be detected in prostate-infiltrating macrophages at 2 weeks postinfection. Further studies performed in the human macrophage cell line THP-1 revealed intracellular survival and persistence of P. acnes but no intracellular replication or escape from the host cell. Confocal analyses of phagosome acidification and maturation were performed. Acidification of P. acnes-containing phagosomes was observed at 6 h postinfection but then lost again, indicative of cytosolic escape of P. acnes or intraphagosomal pH neutralization. No colocalization with the lysosomal markers LAMP1 and cathepsin D was observed, implying that the P. acnes-containing phagosome does not fuse with lysosomes. Our findings give first insights into the intracellular fate of P. acnes; its persistency is likely to be important for the development of P. acnes-associated inflammatory diseases.

  6. Knowledge and acceptability of Chlamydia trachomatis screening among pregnant women and their partners; A cross-sectional study

    NARCIS (Netherlands)

    M.T.R. Pereboom (Monique T.); E.R. Spelten (Evelien); J. Manniën (Judith); G.I.J.G. Rours (Ingrid); S.A. Morré (Servaas A); F.G. Schellevis (François); E.K. Hutton (Eileen K)

    2014-01-01

    textabstractBackground: Chlamydia trachomatis infections in pregnancy can cause maternal disease, adverse pregnancy outcomes and neonatal disease, which is why chlamydia screening during pregnancy has been advocated. The effectiveness of a screening program depends on the knowledge of health care pr

  7. Genital forekomst af Chlamydia trachomatis hos abortsøgende--korrelerer med ung alder og nulliparitet, men ikke tidligere underlivsbetoendelse

    DEFF Research Database (Denmark)

    Sørensen, Jette Led; Thranov, I R; Hoff, G E

    1992-01-01

    Out of 432 women applying for termination of pregnancy, 7.9% (34/428) had cervical Chlamydia trachomatis and 0.7% (3/431) genital Neisseria gonorrhoeae. The prevalence of Chlamydia was 19.2% among the women applying for termination who were under 20 years and 12.8% among those aged 21-25 years...

  8. Genital Chlamydia trachomatis infektion hos abortsøgende. Undersøgelses- og behandlingsstrategi for at mindske infektionssequelae

    DEFF Research Database (Denmark)

    Sørensen, Jette Led; Thranov, I R; Hoff, G E

    1992-01-01

    Among women applying for termination of pregnancy, 5-17% are infected with Chlamydia trachomatis. The prevalence is higher among women under 20 years of age (12-30%), in nulliparae and when Neisseria gonorrhoeae are found simultaneously. If women applying for termination of pregnancy with Chlamydia...

  9. Diatoms respire nitrate to survive dark and anoxic conditions

    DEFF Research Database (Denmark)

    Kamp, Anja; de Beer, Dirk; Nitsch, Jana L.

    2011-01-01

    Diatoms survive in dark, anoxic sediment layers for months to decades. Our investigation reveals a correlation between the dark survival potential of marine diatoms and their ability to accumulate NO3− intracellularly. Axenic strains of benthic and pelagic diatoms that stored 11–274 mM NO3− in th...

  10. Promoting chlamydia screening with posters and leaflets in general practice - a qualitative study

    Directory of Open Access Journals (Sweden)

    Ford-Young William

    2009-10-01

    Full Text Available Abstract Background General practice staff are reluctant to discuss sexual health opportunistically in all consultations. Health promotion materials may help alleviate this barrier. Chlamydia screening promotion posters and leaflets, produced by the English National Chlamydia Screening Programme (NCSP, have been available to general practices, through local chlamydia screening offices, since its launch. In this study we explored the attitudes of general practice staff to these screening promotional materials, how they used them, and explored other promotional strategies to encourage chlamydia screening. Methods Twenty-five general practices with a range of screening rates, were purposively selected from six NCSP areas in England. In focus groups doctors, nurses, administrative staff and receptionists were encouraged to discuss candidly their experiences about their use and opinions of posters, leaflets and advertising to promote chlamydia screening. Researchers observed whether posters and leaflets were on display in reception and/or waiting areas. Data were collected and analysed concurrently using a stepwise framework analytical approach. Results Although two-thirds of screening practices reported that they displayed posters and leaflets, they were not prominently displayed in most practices. Only a minority of practices reported actively using screening promotional materials on an ongoing basis. Most staff in all practices were not following up the advertising in posters and leaflets by routinely offering opportunistic screening to their target population. Some staff in many practices thought posters and leaflets would cause offence or embarrassment to their patients. Distribution of chlamydia leaflets by receptionists was thought to be inappropriate by some practices, as they thought patients would be offended when being offered a leaflet in a public area. Practice staff suggested the development of pocket-sized leaflets. Conclusion The NCSP

  11. Construction of a highly flexible and comprehensive gene collection representing the ORFeome of the human pathogen Chlamydia pneumoniae

    Directory of Open Access Journals (Sweden)

    Maier Christina J

    2012-11-01

    Full Text Available Abstract Background The Gram-negative bacterium Chlamydia pneumoniae (Cpn is the leading intracellular human pathogen responsible for respiratory infections such as pneumonia and bronchitis. Basic and applied research in pathogen biology, especially the elaboration of new mechanism-based anti-pathogen strategies, target discovery and drug development, rely heavily on the availability of the entire set of pathogen open reading frames, the ORFeome. The ORFeome of Cpn will enable genome- and proteome-wide systematic analysis of Cpn, which will improve our understanding of the molecular networks and mechanisms underlying and governing its pathogenesis. Results Here we report the construction of a comprehensive gene collection covering 98.5% of the 1052 predicted and verified ORFs of Cpn (Chlamydia pneumoniae strain CWL029 in Gateway® ‘entry’ vectors. Based on genomic DNA isolated from the vascular chlamydial strain CV-6, we constructed an ORFeome library that contains 869 unique Gateway® entry clones (83% coverage and an additional 168 PCR-verified ‘pooled’ entry clones, reaching an overall coverage of ~98.5% of the predicted CWL029 ORFs. The high quality of the ORFeome library was verified by PCR-gel electrophoresis and DNA sequencing, and its functionality was demonstrated by expressing panels of recombinant proteins in Escherichia coli and by genome-wide protein interaction analysis for a test set of three Cpn virulence factors in a yeast 2-hybrid system. The ORFeome is available in different configurations of resource stocks, PCR-products, purified plasmid DNA, and living cultures of E. coli harboring the desired entry clone or pooled entry clones. All resources are available in 96-well microtiterplates. Conclusion This first ORFeome library for Cpn provides an essential new tool for this important pathogen. The high coverage of entry clones will enable a systems biology approach for Cpn or host–pathogen analysis. The high yield of

  12. Intracardiac intracellular angiotensin system in diabetes.

    NARCIS (Netherlands)

    Kumar, R.; Yong, Q.C.; Thomas, C.M.G.; Baker, K.M.

    2012-01-01

    The renin-angiotensin system (RAS) has mainly been categorized as a circulating and a local tissue RAS. A new component of the local system, known as the intracellular RAS, has recently been described. The intracellular RAS is defined as synthesis and action of ANG II intracellularly. This RAS appea

  13. Chlamydia trachomatis in Women with Ful-Term Deliveries and Women with Abortion

    Directory of Open Access Journals (Sweden)

    Abdolreza S. Jahromi

    2010-01-01

    Full Text Available Problem statement: There are some documents which support the role of some certain infections such as Chlamydia trachomatis in spontaneous abortion. As there were not data about role this bacterium in abortion in this area of IRAN, this study was conducted to evaluate the prevalence of Chlamydia trachomatis in women with abortion and compare it with healthy women with no previous history of abortion. Approach: This case-control study was carried out in Shariatee hospital of Hormozgan University of medical sciences, during 2004-2005. A number of 220 women with definite diagnosis of previous abortion and 200 matched women with normal full term delivery and negative history of miscarriage as controls were studied as case and control groups. All obtained PAP smears from the case and the control groups were then tested using Immunoflourescent method for detection of Chlamydia trachomatis. Data was analyzed, using SPSS software (chi square and t-test. Results: The prevalence of positive direct immunofluorescent test on PAP smears indicating the presence of Chlamydia trachomatis was 56 (25.45% in women with abortion comparing to 13 (5.20% in women in control group, the difference was significant (p = 0.0001. Conclusion: This study showed Chlamydia trachomatis is an important causative agent for abortion in this area of IRAN.

  14. Chlamydia trachomatis serotype A infections in the Amazon region of Brazil: prevalence, entry and dissemination

    Directory of Open Access Journals (Sweden)

    Marluísa de Oliveira Guimarães Ishak

    2015-04-01

    Full Text Available INTRODUCTION: Chlamydia infection is associated with debilitating human diseases including trachoma, pneumonia, coronary heart disease and urogenital diseases. Serotypes of C. trachomatis show a fair correlation with the group of diseases they cause, and their distribution follows a well-described geographic pattern. Serotype A, a trachoma-associated strain, is known for its limited dissemination in the Middle East and Northern Africa. However, knowledge on the spread of bacteria from the genus Chlamydia as well as the distribution of serotypes in Brazil is quite limited. METHODS: Blood samples of 1,710 individuals from ten human population groups in the Amazon region of Brazil were examined for antibodies to Chlamydia using indirect immunofluorescence and microimmunofluorescence assays. RESULTS: The prevalence of antibodies to Chlamydia ranged from 23.9% (Wayana-Apalai to 90.7% (Awa-Guaja with a mean prevalence of 50.2%. Seroreactivity was detected to C. pneumoniae and to all serotypes of C. trachomatis tested; furthermore, we report clear evidence of the as-yet-undescribed occurrence of serotype A of C. trachomatis. CONCLUSIONS: Specific seroreactivity not only accounts for the large extent of dissemination of C. trachomatis in the Amazon region of Brazil but also shows an expanded area of occurrence of serotype A outside the epidemiological settings previously described. Furthermore, these data suggest possible routes of Chlamydia introduction into the Amazon region from the massive human migration that occurred during the 1,700s.

  15. Comparative Assessment of Chlamydia trachomatis Infection in Iranian Women with Cervicitis: A Cross-Sectional Study

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    J Zaeimi Yazdi

    2006-06-01

    Full Text Available Chlamydia trachomatis infections are the most prevalent bacterial sexually transmitted infections (STI recognized throughout the world. The aim of this study was to determine the prevalence of Chlamydia trachomatis among a randomized statistical group of women suffering from cervicitis in Tehran- Iran. During a 12- month- period, Jan 2003 to Jan 2004, 142 endocervical samples were taken from women suffering from cervicitis attending to Mirzakoochakkhan Women Hospital in Tehran, Iran. Direct fluorescent antibody (DFA and PCR techniques were used to detect Chlamydia trachomatis in endocervical samples. Twenty two (15.5% [95% CI, 9.54-21.4] of 142 samples were diagnosed as Chlamydia positive according to PCR results, while DFA diagnosed 20 (14.1% positive cases [95% CI, 8.37-19.8]. No statistically significant difference was found between two diagnosis methods applied in this study. The prevalence was the highest (25% among women aged 25 to 29 yr and 35 to 39 yr. The x 2 test showed a significant relationship between positive test result and bearing a history of STI (P= 0. The results of this study showed high prevalence of C. trachomatis infection among women suffering from cervicitis and suggested that patients diagnosed with genital Chlamydia infection should be referred to the genitourinary medicine clinic for further STI screening and partner notification.

  16. Brief Report: Gonorrhea and Chlamydia Testing Increasing but Still Lagging in HIV Clinics in the United States.

    Science.gov (United States)

    Berry, Stephen A; Ghanem, Khalil G; Mathews, William Christopher; Korthuis, Philip Todd; Yehia, Baligh R; Agwu, Allison L; Lehmann, Christoph U; Moore, Richard D; Allen, Sara L; Gebo, Kelly A

    2015-11-01

    Screening persons living with HIV for gonorrhea and chlamydia has been recommended since 2003. We compared annual gonorrhea/chlamydia testing to syphilis and lipid testing among 19,368 adults (41% men who have sex with men, 30% heterosexual men, and 29% women) engaged in HIV care. In 2004, 22%, 62%, and 70% of all patients were tested for gonorrhea/chlamydia, syphilis, and lipid levels, respectively. Despite increasing steadily [odds ratio per year (95% confidence interval): 1.14 (1.13 to 1.15)], gonorrhea/chlamydia testing in 2010 remained lower than syphilis and lipid testing (39%, 77%, 76%, respectively). Interventions to improve gonorrhea/chlamydia screening are needed. A more targeted screening approach may be warranted.

  17. Interplay of recombination and selection in the genomes of Chlamydia trachomatis

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    Dean Deborah

    2011-05-01

    Full Text Available Abstract Background Chlamydia trachomatis is an obligate intracellular bacterial parasite, which causes several severe and debilitating diseases in humans. This study uses comparative genomic analyses of 12 complete published C. trachomatis genomes to assess the contribution of recombination and selection in this pathogen and to understand the major evolutionary forces acting on the genome of this bacterium. Results The conserved core genes of C. trachomatis are a large proportion of the pan-genome: we identified 836 core genes in C. trachomatis out of a range of 874-927 total genes in each genome. The ratio of recombination events compared to mutation (ρ/θ was 0.07 based on ancestral reconstructions using the ClonalFrame tool, but recombination had a significant effect on genetic diversification (r/m = 0.71. The distance-dependent decay of linkage disequilibrium also indicated that C. trachomatis populations behaved intermediately between sexual and clonal extremes. Fifty-five genes were identified as having a history of recombination and 92 were under positive selection based on statistical tests. Twenty-three genes showed evidence of being under both positive selection and recombination, which included genes with a known role in virulence and pathogencity (e.g., ompA, pmps, tarp. Analysis of inter-clade recombination flux indicated non-uniform currents of recombination between clades, which suggests the possibility of spatial population structure in C. trachomatis infections. Conclusions C. trachomatis is the archetype of a bacterial species where recombination is relatively frequent yet gene gains by horizontal gene transfer (HGT and losses (by deletion are rare. Gene conversion occurs at sites across the whole C. trachomatis genome but may be more often fixed in genes that are under diversifying selection. Furthermore, genome sequencing will reveal patterns of serotype specific gene exchange and selection that will generate important

  18. Chlamydia trachomatis C-complex serovars are a risk factor for preterm birth

    DEFF Research Database (Denmark)

    Hollegaard, Stine; Vogel, Ida; Thorsen, Poul;

    2007-01-01

    , Chlamydia antigen, Chlamydia IgG, Chlamydia complex B, C and GF levels were measured. Spontaneous preterm birth (ectopic pregnancies. Crude and adjusted relative risks (RR......) and odds ratios (OR) were estimated by logistic regression. RESULTS: C. trachomatis C-complex positivity was associated with spontaneous PTB [RR 2.6 (1.1-6.29)] and additionally with a prior history of subfertility [OR 4.4 [2.5-7.7]), infertility treatment [OR 7.2 (4.0-12.8)] and ectopic pregnancy [5.2 (2.......2-12.4)]. CONCLUSION: A previous infection with C. trachomatis C-complex was associated with an increased risk for spontaneous PTB and may potentially contribute to subfertility, infertility and ectopic pregnancy....

  19. [Cervicitis--epidemiological and clinical risk for Chlamydia trachomatis infection in university students].

    Science.gov (United States)

    Schilling, A; Stevenson, M

    1994-01-01

    Fifty volunteer, asymptomatic sexually active university female students were examined and inquired, in order to find risk factors predictive of Chlamydia trachomatis infection. Epidemiologic and behavioral factors (age, number of sexual partners, oral contraceptives use and history of previous sexually transmitted diseases) were found to be similar among the studied group and published data for North American female college students, but barrier contraceptive methods use was found to be different. Twenty two per cent of the sample had clinical cervicitis, and 30% had subclinical. If the screening models proposed by different authors would have been applied, between a 32% and 72% of the sample would have been selectively for the presence of Chlamydia trachomatis. It is concluded that international sugerences about Chlamydia trachomatis screening should be adopted until national experiences are made.

  20. [THE ROLE OF SYSTEM QUORUM SENSING UNDER CHRONIC UROGENITAL CHLAMYDIA INFECTION].

    Science.gov (United States)

    2015-10-01

    It is established that system quorum sensing (QS) assure social behavior of bacteria in regulation of genes of virulence and generalization of inflectional inflammatory process under chronic urogenital chlamydia infection. The techniques of gas chromatography and mass-spectrometry were applied to detect molecular markers of generalization of infectious process under urogenital chlamydiasis--activators of QS microbes (lactones, quinolones, furan ethers). The developed diagnostic gas chromatography and mass-spectrometry criteria of indexation of molecular markers under chronic urogenital chlamydia infection have high level of diagnostic sensitivity, specificity and prognostic value of positive and negative result. The application of techniques of gas chromatography and mass-spectrometry permits enhancing effectiveness of diagnostic of chronic inflectional inflammatory diseases of urogenital system of chlamydia etiology with identification of prognostic criteria of generalization of infectious process and subsequent prescription of timely and appropriate therapy

  1. Seroprevalence of Chlamydia infection in pigs in Jiangxi province, South-Eastern China.

    Science.gov (United States)

    Jiang, H H; Huang, S Y; Zhang, W B; Zhao, L; Xu, C M; Deng, S Z; Zhu, X Q

    2013-12-01

    Chlamydia are Gram-negative obligate bacteria that cause a wide range of diseases in humans and animals. To assess the risk of zoonosis posed by pigs, a total of 920 serum samples were collected from pigs in 11 administrative cities in Jiangxi province, south-eastern China, and the seroprevalence of Chlamydia antibodies was investigated by an indirect haemagglutination assay. The pathogen-specific antibodies were detected in 539 (58.59 %) pigs with seroprevalence ranging from 33.33 % (Jingdezhen) to 90.91 % (Pingxiang) among different cities (PChlamydia infection among different categories of pigs was also significantly different (PChlamydia is highly prevalent in pigs in Jiangxi province and our results indicate that the presence of Chlamydia exposure in pigs may pose a potential threat to human health.

  2. [MEDICAL AND SOCIAL STATE OF HEALTH IN FAMILIES WITH THE FOCUS OF RESPIRATORY CHLAMYDIA].

    Science.gov (United States)

    Kapustina, T A; Markina, A N; Parilova, O V; Belova, E V; Kin, T I

    2015-01-01

    Medical and social state of health in family persons was assessed on the basis of a questionnaire. Developed by the author's questionnaire included two sections, reflecting the state of health, health risk factors and social characteristics of the family members of ENT patients. In the article there is presented an analysis of the medical and social state of 44 families of patients with diseases of the upper respiratory tract associated with chlamydial infection. The comparison was performed with 43 families of ENT patients with unconfirmed respiratory chlamydia. Diagnosis of Chlamydia infection complex was carried out with the use of laboratory methods (direct immunofluorescence and enzyme-linked immunosorbent assays, polymerase chain reaction). The health and social status of families with hearth respiratory chlamydia were shown to be significantly worse compared with families with the lack of the latter

  3. Chlamydia trachomatis infection results in a modest pro-inflammatory cytokine response and a decrease in T cell chemokine secretion in human polarized endocervical epithelial cells.

    Science.gov (United States)

    Buckner, Lyndsey R; Lewis, Maria E; Greene, Sheila J; Foster, Timothy P; Quayle, Alison J

    2013-08-01

    strategies, together with the inherent immune repertoire of endocervical epithelial cells, may aid chlamydiae in establishing, and possibly sustaining, an intracellular niche in microenvironments of the endocervix in vivo.

  4. Relationship between Chlamydia pneumoniae infection and occurrence of bronchial asthma

    Institute of Scientific and Technical Information of China (English)

    SHI Yi; ZHENG Wen; XIA Xi-rong; ZHANG Xi-long; TONG Mao-rong; FENG Gen-bao; ZHAO Bei-lei; HU Lan-ping

    2002-01-01

    Objective: To study the relationship between Chlamydia pneumoniae (C. Pneumoniae) infection and asthma exacerbation. Methods: A prospective study of C. Pneumoniae infection was conducted in 75 patients with asthma and 63 patients with respiratory tract infection, and 100 blood donors served as controls.The presence of infection was convinced by the polymerase chain reaction and direct immunofluorescence assay for C. Pneumoniae DNA from throat swab specimens and micro-immunofluorescence testing for C. Pneumoniae-specific IgG, IgM and IgA antibodies. Results: Prevalence of specific IgG in asthma patients (81.3%) was higher than that of the blood donors (68. 0%, P<0. 05) and was not significantly different from respiratory tract infection patients (68. 0%, P>0. 05). The acute C. Pneumoniae infection rate of symptomatic asthma patients (59.4%) was markedly higher than that of respiratory tract infection patients (34.9%, P<0. 05). The average titer of C. Pneumoniae IgG instead of IgA in asthma patients (48. 38±6. 94)was significantly higher than respiratory tract infection patients (24. 70±8. 77, P<0. 05). Other pathogens were identified in 12 of 21 (57. 1%) asthma patients with C. Pneumoniae. The symptoms of 7 asthma patients with C. Pneumoniae infection were improved through antibiotic treatment. Conclusion: The findings suggest a possible role of C. Pneumoniae infection in asthma.

  5. Effects of Mentha suaveolens essential oil on Chlamydia trachomatis.

    Science.gov (United States)

    Sessa, Rosa; Di Pietro, Marisa; De Santis, Fiorenzo; Filardo, Simone; Ragno, Rino; Angiolella, Letizia

    2015-01-01

    Chlamydia trachomatis, the most common cause of sexually transmitted bacterial infection worldwide, has a unique biphasic developmental cycle alternating between the infectious elementary body and the replicative reticulate body. C. trachomatis is responsible for severe reproductive complications including pelvic inflammatory disease, ectopic pregnancy, and obstructive infertility. The aim of our study was to evaluate whether Mentha suaveolens essential oil (EOMS) can be considered as a promising candidate for preventing C. trachomatis infection. Specifically, we investigated the in vitro effects of EOMS towards C. trachomatis analysing the different phases of chlamydial developmental cycle. Our results demonstrated that EOMS was effective towards C. trachomatis, whereby it not only inactivated infectious elementary bodies but also inhibited chlamydial replication. Our study also revealed the effectiveness of EOMS, in combination with erythromycin, towards C. trachomatis with a substantial reduction in the minimum effect dose of antibiotic. In conclusion, EOMS treatment may represent a preventative strategy since it may reduce C. trachomatis transmission in the population and, thereby, reduce the number of new chlamydial infections and risk of developing of severe sequelae.

  6. The pathogenesis of Chlamydia pneumoniae-type pneumonitis in mice

    Institute of Scientific and Technical Information of China (English)

    施毅; 印洁; 詹化文; 冯根宝; 张希龙; 苏欣; 宋勇; 夏锡荣; 周晓军; 申萍

    2003-01-01

    Objective To evaluate mice as experimental animals for Chlamydia pneumoniae (C.pneumoniae) infection and investigate the pathogenesis of C.pneumoniae derived pneumonitis.Methods Icr mice were inoculated with the C.pneumoniae strain, CWL-029, either intranasally or intravenously. After a single dose inoculation, mice were killed on the 1st, 3rd, 7th, 14th, 21st, 28th and 60th days. The pathological changes in lung tissue were analyzed.Results The Icr mice were shown to be susceptible to C.pneumoniae. Inoculation into mice with C.pneumoniae induced a prolonged course of lung infection, as demonstrated by persistence of lung pathology (up to 60 days). Via intranasal inoculation of mice, lung pathology was characterized by patchy interstitial pneumonitis with predominately neutrophil leukocyte infiltration early (within the first 7 days) and lymphocyte infiltration in the later stages (14 days later) of infection. After intravenous inoculation, a similarly developed interstitial pneumonitis was observed, but it was milder and patchier, especially in early stages. C.pneumoniae DNA was detected by polymerase chain reaction (PCR) intermittently in the lung tissue. Inoculated mice developed serum IgG antibody responses.Conclusion The Icr mice were susceptible to C.pneumoniae, resulting in a pulmonary infection characterized by interstitial pneumonitis, occurring most strongly via intranasal inoculation.

  7. Effects of vaginal lactobacilli in Chlamydia trachomatis infection.

    Science.gov (United States)

    Mastromarino, Paola; Di Pietro, Marisa; Schiavoni, Giovanna; Nardis, Chiara; Gentile, Massimo; Sessa, Rosa

    2014-07-01

    Increasing evidence indicates that abnormal vaginal flora lacking lactobacilli facilitates the acquisition of several sexually transmitted diseases including Chlamydia trachomatis. C. trachomatis, the most common bacterial agent of genital infections worldwide, can progress from the lower to upper reproductive tract and induce severe sequelae. The ability of C. trachomatis to develop into a persistent form has been suggested as key pathogenetic mechanism underlying chronic infections and sequelae. The aim of our study was to investigate the C. trachomatis interaction with vaginal microbiota analyzing the effects of Lactobacillus strains (L. brevis and L. salivarius) on the different phases of C. trachomatis developmental cycle. In addition, the effect of lactobacilli on persistent chlamydial forms induced by HSV-2 coinfection has also been evaluated. Our results demonstrated significant inhibition of C. trachomatis multiplication by vaginal lactobacilli. L. brevis was significantly more effective than L. salivarius (plactobacilli to protect from infection is strain-dependent. Lactobacilli had an adverse effect on elementary chlamydial bodies (plactobacilli toward persistent C. trachomatis forms induced by HSV-2 coinfection. A significant increase in the production of C. trachomatis infectious progeny was observed in C. trachomatis/HSV-2 coinfection in the presence of L. brevis (p=0.01) despite a significant inhibition of C. trachomatis multiplication (p=0.028). Our data suggest that a healthy vaginal microbiota can reduce the risk of acquiring C. trachomatis infection and counteract the development of persistent chlamydial forms.

  8. Chlamydia psittaci infection in canaries heavily infested by Dermanyssus gallinae.

    Science.gov (United States)

    Circella, Elena; Pugliese, N; Todisco, G; Cafiero, M A; Sparagano, O A E; Camarda, A

    2011-12-01

    Dermanyssus gallinae is a haematophagous ectoparasite responsible for anemia, weight loss, dermatitis and a decrease in egg production. Dermanyssus gallinae may play a role in the modulation of the host immune system, maybe predisposing the host to some bacterial infections such as chlamydiosis. This is an important zoonosis. Humans are exposed to Chlamydia psittaci through inhalation of the agent dispersed from the infected birds. In this study, a syndrome observed in an aviary of canaries was investigated. A heavy infestation by D. gallinae was reported. Simultaneously, a C. psittaci infection was molecularly confirmed in the canaries. Combined therapy was applied successfully. The association of C. psittaci with the examined mites has been confirmed. Therefore, we think that D. gallinae have played a role in the spreading of C. psittaci infection among the canaries. Moreover, D. gallinae could have played an important role predisposing the canaries to the development of chlamydiosis, by inducing anemia and debilitation. The control of mites in the aviaries may represent a crucial step for the prevention of important infection such as chlamydiosis in birds and humans.

  9. Flavonoid Naringenin: A Potential Immunomodulator for Chlamydia trachomatis Inflammation

    Directory of Open Access Journals (Sweden)

    Abebayehu N. Yilma

    2013-01-01

    Full Text Available Chlamydia trachomatis, the agent of bacterial sexually transmitted infections, can manifest itself as either acute cervicitis, pelvic inflammatory disease, or a chronic asymptomatic infection. Inflammation induced by C. trachomatis contributes greatly to the pathogenesis of disease. Here we evaluated the anti-inflammatory capacity of naringenin, a polyphenolic compound, to modulate inflammatory mediators produced by mouse J774 macrophages infected with live C. trachomatis. Infected macrophages produced a broad spectrum of inflammatory cytokines (GM-CSF, TNF, IL-1β, IL-1α, IL-6, IL-12p70, and IL-10 and chemokines (CCL4, CCL5, CXCL1, CXCL5, and CXCL10 which were downregulated by naringenin in a dose-dependent manner. Enhanced protein and mRNA gene transcript expressions of TLR2 and TLR4 in addition to the CD86 costimulatory molecule on infected macrophages were modulated by naringenin. Pathway-specific inhibition studies disclosed that p38 mitogen-activated-protein kinase (MAPK is involved in the production of inflammatory mediators by infected macrophages. Notably, naringenin inhibited the ability of C. trachomatis to phosphorylate p38 in macrophages, suggesting a potential mechanism of its attenuation of concomitantly produced inflammatory mediators. Our data demonstrates that naringenin is an immunomodulator of inflammation triggered by C. trachomatis, which possibly may be mediated upstream by modulation of TLR2, TLR4, and CD86 receptors on infected macrophages and downstream via the p38 MAPK pathway.

  10. Seropositivity for Chlamydia Pneumoniae and Mycoplasma Pneumoniae in Asthmatic Children

    Directory of Open Access Journals (Sweden)

    Murat Tutanc

    2014-03-01

    Full Text Available Acute respiratory tract infections may trigger acute asthma attacks and may be held responsible for etiopathogenesis in children with asthma. Although bacterial infections attract a limited amount of attention, recently Chlamydia pneumoniae (CP and Mycoplasma pneumoniae (MP, in particular, are reported to be the possible factors. IgM and IgG seroprevalence was investigated in 66 children patients with bronchial asthma (between the ages of 3 and 14 for CP and Mycoplasma pneumoniae. In a total of 66 cases, 18 (27.2% patients were detected with IgG positivity for CP whereas 27 of them (40.9% were detected with IgG positivity for MP. IgG positivity was determined in 6 patients (13.0% in the control group for CP, and in 6 patients (10.8% in the control group for MP. The rate of the asthma patients with IgG seropositivity for MP was 4 times higher than that of the control group. It was seen that IgG antibody seropositivity for CP was higher in those with more frequent attacks. No such difference was observed in terms of IgG antibody seropositivity for M. pneumoniae. There are many studies indicating that CP and MP infections take an importance place in the etiology of bronchial asthma and asthma attacks in children. The results obtained reveal the effect of both microorganisms on the etiopathogenesis of the bronchial asthma and the increased number of asthma attacks.

  11. [Cervical intraepithelial neoplasia: Chlamydia trachomatis and other co-factors].

    Science.gov (United States)

    Núñez-Troconis, J T

    1995-09-01

    The incidence of Chlamydia trachomatis (Ct) in patients with diagnosis of Cervical Intraepithelial Neoplasia (CIN) was studied in one hundred eighty patients. The Chlamydiazyme test was performed in all of them. Endocervical samples were taken from 103 patients with CIN and 77 women who sought medical attention for different gynecological reasons (CG). Twenty three tests (12.8%) were positive; 15 of them had CIN (14.6%) and 8 were from the control group (10.4%). It was found a statistical significant difference between NIC III and early intercourse, NIC III and age, NIC and vaginal douches and, among NIC and number of pregnancies and deliveries. There was not a significant difference among Ct and early intercourse, number of sexual partners, pregnancies, deliveries, vaginal douches, oral contraceptives (OC), and vaginal discharge. No statistically significant differences were found between NIC and number of sexual partners, and OC and vaginal discharge. The low incidence of Ct in patients with CIN does not mean that Ct does not play a role in the origin and development of the cervical pathology.

  12. Chlamydia Trachomatis and Ureaplasma Urealyticum Transmission Between Regular Sexual Partners

    Institute of Scientific and Technical Information of China (English)

    刘全中; 齐蔓莉; 缴稳苓

    2003-01-01

    Objective: To investigate the transmission ratio and epidemiology of Chlamydia trachomatis (Ct) and Ureaplasma urealyticum (Uu) between regular sexual partners. Methods: We collected secretion specimens of geni-tourinary tract from sexual partners who attended our clinic during the period from May 1, 1999 to May 31,2000 and then detected Ct and Uu in the specimens. Results: The inconsistent rate of Ct and Uu infected between sexual partners was 59.22% and 38.92% respectively. There were no correlations between pa-tients' age and the inconsistent rate of Ct and Uu in-fected (P>0.05). The most common inconsistency be-tween regular partners was seen in man with Ct infec-tion while in female with Uu infection; and in man with concurrent infection of Ct while in female only with Uu; or in man with Ct infection while in female no Ct and Uu were detected. Conclusion: The sexual transmitting ability of Ct and Uu is not as active as we have expected.

  13. Longitudinal prevalence and faecal shedding of Chlamydia pecorum in sheep.

    Science.gov (United States)

    Yang, Rongchang; Jacobson, Caroline; Gardner, Graham; Carmichael, Ian; Campbell, Angus J D; Ryan, Una

    2014-09-01

    The prevalence and faecal shedding of Chlamydia spp. in sheep in Australia has not been well described. Two species-specific quantitative PCRs (qPCRs) targeting the chlamydial outer membrane protein cell surface antigen gene (ompA) were validated and used to determine the prevalence and faecal shedding of C. abortus and C. pecorum from faecal samples of lambs at three sampling times (weaning, post-weaning and pre-slaughter) from eight farms in South Australia, New South Wales, Victoria and Western Australia. A total of 3412 faecal samples were collected and screened from approximately 1189 lambs across the four states. C. abortus was not detected in any of the samples screened. The overall prevalence of C. pecorum was 1027/3412 (30.1%) and median bacterial concentrations at weaning, post-weaning and pre-slaughter were 1.8 × 10(7), 1.2 × 10(7) and 9.6 × 10(5)/g faeces, respectively. A subset of C. pecorum positive samples from each farm, (n = 48) was sequenced to confirm their identity. The present study demonstrates that C. pecorum is prevalent in Australian sheep, highlighting a need for further research on the impact of this bacterium on production.

  14. Chlamydia abortus in Cows Oviducts, Occasional Event or Causal Connection?

    Science.gov (United States)

    Appino, S; Vincenti, L; Rota, A; Pellegrini, S; Chieppa, M N; Cadoni, V; Pregel, P

    2015-06-01

    Fifty-seven genital tracts of regularly slaughtered culled Piedmontese cows, aged 7.4 ± 4.3 years (mean ± SD), range: 2.6-15.6 years, were grossly and microscopically examined. DNA extracted from oviducts was subjected to PCR to evaluate the presence of Chlamydia spp. The 15 PCR-positive oviducts were subjected to Sanger sequencing and showed the presence of Chamydia abortus, with an identity range between 99 and 100%. Nine of the PCR-positive samples belonged to the 24 animals with a normal macroscopic appearance of the whole genital tract (percentage of positive oviducts in normal genital tracts 9/24 = 37.5%), while six belonged to the 33 genital tracts with lesions in one or more organs (percentage of positive oviducts in pathological genital tracts 6/33 = 18.1%); of these, a single animal had salpingitis. The detection of C. abortus in bovine oviducts is of particular interest because it has never been previously investigated or reported.

  15. Effects of Mentha suaveolens Essential Oil on Chlamydia trachomatis

    Directory of Open Access Journals (Sweden)

    Rosa Sessa

    2015-01-01

    Full Text Available Chlamydia trachomatis, the most common cause of sexually transmitted bacterial infection worldwide, has a unique biphasic developmental cycle alternating between the infectious elementary body and the replicative reticulate body. C. trachomatis is responsible for severe reproductive complications including pelvic inflammatory disease, ectopic pregnancy, and obstructive infertility. The aim of our study was to evaluate whether Mentha suaveolens essential oil (EOMS can be considered as a promising candidate for preventing C. trachomatis infection. Specifically, we investigated the in vitro effects of EOMS towards C. trachomatis analysing the different phases of chlamydial developmental cycle. Our results demonstrated that EOMS was effective towards C. trachomatis, whereby it not only inactivated infectious elementary bodies but also inhibited chlamydial replication. Our study also revealed the effectiveness of EOMS, in combination with erythromycin, towards C. trachomatis with a substantial reduction in the minimum effect dose of antibiotic. In conclusion, EOMS treatment may represent a preventative strategy since it may reduce C. trachomatis transmission in the population and, thereby, reduce the number of new chlamydial infections and risk of developing of severe sequelae.

  16. Evaluation of patients with dry eye disease for conjunctival Chlamydia trachomatis and Ureaplasma urealyticum

    Science.gov (United States)

    Abdelfattah, Maha Mohssen; Khattab, Rania Abdelmonem; Mahran, Magda H.; Elborgy, Ebrahim S.

    2016-01-01

    AIM To determine the possibility of the development of dry eye disease (DED) as a result of persistent infection with Chlamydia trachomatis and Ureaplasma urealyticum in the conjunctiva of patients. METHODS This study was conducted on 58 patients of age range 20-50y, diagnosed with DED confirmed by Schirmer I test and tear breakup time. The non-dry eye control group included 27 subjects of the same age. Ocular specimens were collected as conjunctival scrapings and swabs divided into three groups: the first used for bacterial culture, the second and third taken to detect Chlamydia trachomatis and Ureaplasma urealyticum by direct fluorescent antibody (DFA) assay and polymerase chain reaction (PCR) method. RESULTS Chlamydia trachomatis was detected in 65.5% and 76% of DED patients by DFA and PCR methods respectively. Ureaplasma urealyticum was found in 44.8% of DED infected patients using the PCR method. Both organisms were identified in only 37.9% of DED patients found to be infected. Control subjects had a 22% detection rate of Chlamydia trachomatis by DFA assay versus a 7% detection rate by PCR; while Ureaplasma urealyticum was detected in 3.7% of the controls by PCR method. The conjunctival culture revealed that gram positive microorganisms represented 75% of isolates with coagulase negative Staphylococci the most common (50%) followed by Staphylococcus aureus (20%), whereas gram negative microorganisms occurred in 25% of cases, isolating Moraxella spp. as the most frequent organism. CONCLUSION Our results tend to point out that Chlamydia trachomatis and Ureaplasma urealyticum were detected in a moderate percentage of patients with DED, and could be a fair possibility for its development. PCR is more reliable in detecting Chlamydia trachomatis than DFA technique. The presence of isolated conjunctival bacterial microflora can be of some potential value. PMID:27803864

  17. Performance of three microimmunofluorescence assays for detection of Chlamydia pneumoniae immunoglobulin M, G, and A antibodies

    DEFF Research Database (Denmark)

    Bennedsen, Mette; Berthelsen, Lene; Lind, Inga

    2002-01-01

    Labsystems (LAB) and MRL Diagnostics (MRL) by investigation of sera from three groups of patients: group I, 83 sera from 28 patients with atypical pneumonia; group II, 37 sera from 16 patients with acute C. pneumoniae or Chlamydia psittaci respiratory tract infection confirmed by PCR or culture; group III......The microimmunofluorescence (MIF) test is considered the "gold standard" for laboratory diagnosis of acute and chronic Chlamydia pneumoniae infection. The performance of a MIF test based on C. pneumoniae antigen from Washington Research Foundation (WRF) was compared with those of assays from...

  18. Mathematical analysis of a Chlamydia epidemic model with pulse vaccination strategy.

    Science.gov (United States)

    Samanta, G P

    2015-03-01

    In this paper, we have considered a dynamical model of Chlamydia disease with varying total population size, bilinear incidence rate and pulse vaccination strategy. We have defined two positive numbers R₀ and (R₁≤ R₀). It is proved that there exists an infection-free periodic solution which is globally attractive if R₀ 1 The important mathematical findings for the dynamical behaviour of the Chlamydia disease model are also numerically verified using MATLAB. Finally epidemiological implications of our analytical findings are addressed critically.

  19. Prevalence of cervical Chlamydia trachomatis and Neisseria gonorrhoeae in female adolescents.

    Science.gov (United States)

    Fraser, J J; Rettig, P J; Kaplan, D W

    1983-03-01

    The prevalence of cervical infection with Chlamydia trachomatis and Neisseria gonorrhoeae was examined in 125 girls receiving primary gynecologic care in a general adolescent clinic. C trachomatis was isolated in 8% of the patients using a microtiter tissue-culture method, and N gonorrhoeae was found in 12%. A significant association was found between the use of oral contraceptives and positive chlamydial cultures. Patients with Chlamydia-positive cultures were frequently asymptomatic and exhibited no positive findings on physical examination. Three of ten women with cervical chlamydial infection developed pelvic inflammatory disease. These results support the use of cervical screening for both of these pathogens in sexually active adolescents.

  20. Quantitative Proteomics of Intracellular Campylobacter jejuni Reveals Metabolic Reprogramming.

    Directory of Open Access Journals (Sweden)

    Xiaoyun Liu

    Full Text Available Campylobacter jejuni is the major cause of bacterial food-borne illness in the USA and Europe. An important virulence attribute of this bacterial pathogen is its ability to enter and survive within host cells. Here we show through a quantitative proteomic analysis that upon entry into host cells, C. jejuni undergoes a significant metabolic downshift. Furthermore, our results indicate that intracellular C. jejuni reprograms its respiration, favoring the respiration of fumarate. These results explain the poor ability of C. jejuni obtained from infected cells to grow under standard laboratory conditions and provide the bases for the development of novel anti microbial strategies that would target relevant metabolic pathways.

  1. Intracellular Assessment of ATP Levels in Caenorhabditis elegans

    Science.gov (United States)

    Palikaras, Konstantinos; Tavernarakis, Nektarios

    2017-01-01

    Eukaryotic cells heavily depend on adenosine triphosphate (ATP) generated by oxidative phosphorylation (OXPHOS) within mitochondria. ATP is the major energy currency molecule, which fuels cell to carry out numerous processes, including growth, differentiation, transportation and cell death among others (Khakh and Burnstock, 2009). Therefore, ATP levels can serve as a metabolic gauge for cellular homeostasis and survival (Artal-Sanz and Tavernarakis, 2009; Gomes et al., 2011; Palikaras et al., 2015). In this protocol, we describe a method for the determination of intracellular ATP levels using a bioluminescence approach in the nematode Caenorhabditis elegans. PMID:28194429

  2. Palladium-mediated intracellular chemistry

    Science.gov (United States)

    Yusop, Rahimi M.; Unciti-Broceta, Asier; Johansson, Emma M. V.; Sánchez-Martín, Rosario M.; Bradley, Mark

    2011-03-01

    Many important intracellular biochemical reactions are modulated by transition metals, typically in the form of metalloproteins. The ability to carry out selective transformations inside a cell would allow researchers to manipulate or interrogate innumerable biological processes. Here, we show that palladium nanoparticles trapped within polystyrene microspheres can enter cells and mediate a variety of Pd0-catalysed reactions, such as allylcarbamate cleavage and Suzuki-Miyaura cross-coupling. The work provides the basis for the customization of heterogeneous unnatural catalysts as tools to carry out artificial chemistries within cells. Such in cellulo synthesis has potential for a plethora of applications ranging from cellular labelling to synthesis of modulators or inhibitors of cell function.

  3. Host-pathogen interactions in specific pathogen-free chickens following aerogenous infection with Chlamydia psittaci and Chlamydia abortus.

    Science.gov (United States)

    Kalmar, Isabelle; Berndt, Angela; Yin, Lizi; Chiers, Koen; Sachse, Konrad; Vanrompay, Daisy

    2015-03-15

    Although Chlamydia (C.) psittaci infections are recognized as an important factor causing economic losses and impairing animal welfare in poultry production, the specific mechanisms leading to severe clinical outcomes are poorly understood. In the present study, we comparatively investigated pathology and host immune response, as well as systemic dissemination and expression of essential chlamydial genes in the course of experimental aerogeneous infection with C. psittaci and the closely related C. abortus, respectively, in specific pathogen-free chicks. Clinical signs appeared sooner and were more severe in the C. psittaci-infected group. Compared to C. abortus infection, more intense systemic dissemination of C. psittaci correlated with higher and faster infiltration of immune cells, as well as more macroscopic lesions and epithelial pathology, such as hyperplasia and erosion. In thoracic air sac tissue, mRNA expression of immunologically relevant factors, such as IFN-γ, IL-1β, IL-6, IL-17, IL-22, LITAF and iNOS was significantly stronger up-regulated in C. psittaci- than in C. abortus-infected birds between 3 and 14 days post-infection. Likewise, transcription rates of the chlamydial genes groEL, cpaf and ftsW were consistently higher in C. psittaci during the acute phase. These findings illustrate that the stronger replication of C. psittaci in its natural host also evoked a more intense immune response than in the case of C. abortus infection.

  4. Culture-independent genome sequencing of clinical samples reveals an unexpected heterogeneity of infections by Chlamydia pecorum.

    Science.gov (United States)

    Bachmann, Nathan L; Sullivan, Mitchell J; Jelocnik, Martina; Myers, Garry S A; Timms, Peter; Polkinghorne, Adam

    2015-05-01

    Chlamydia pecorum is an important global pathogen of livestock, and it is also a significant threat to the long-term survival of Australia's koala populations. This study employed a culture-independent DNA capture approach to sequence C. pecorum genomes directly from clinical swab samples collected from koalas with chlamydial disease as well as from sheep with arthritis and conjunctivitis. Investigations into single-nucleotide polymorphisms within each of the swab samples revealed that a portion of the reads in each sample belonged to separate C. pecorum strains, suggesting that all of the clinical samples analyzed contained mixed populations of genetically distinct C. pecorum isolates. This observation was independent of the anatomical site sampled and the host species. Using the genomes of strains identified in each of these samples, whole-genome phylogenetic analysis revealed that a clade containing a bovine and a koala isolate is distinct from other clades comprised of livestock or koala C. pecorum strains. Providing additional evidence to support exposure of koalas to Australian livestock strains, two minor strains assembled from the koala swab samples clustered with livestock strains rather than koala strains. Culture-independent probe-based genome capture and sequencing of clinical samples provides the strongest evidence yet to suggest that naturally occurring chlamydial infections are comprised of multiple genetically distinct strains.

  5. Non-detection of Chlamydia species in carotid atheroma using generic primers by nested PCR in a population with a high prevalence of Chlamydia pneumoniae antibody

    Directory of Open Access Journals (Sweden)

    Bamford Kathleen B

    2001-08-01

    Full Text Available Abstract Background The association of Chlamydia pneumoniae with atherosclerosis is controversial. We investigated the presence of C. pneumoniae and other Chlamydia spp. in atheromatous carotid artery tissue. Methods Forty elective carotid endarterectomy patients were recruited (27 males, mean age 65 and 13 females mean age 68, 4 had bilateral carotid endarterectomies (n= 44 endarterectomy specimens. Control specimens were taken from macroscopically normal carotid artery adjacent to the atheromatous lesions (internal controls, except in 8 cases where normal carotid arteries from post mortem (external controls were used. Three case-control pairs were excluded when the HLA DRB gene failed to amplify from the DNA. Genus specific primers to the major outer membrane protein (MOMP gene were used in a nested polymerase chain reaction (nPCR in 41 atheromatous carotid specimens and paired controls. PCR inhibition was monitored by spiking with target C. trachomatis. Atheroma severity was graded histologically. Plasma samples were tested by microimmunofluorescence (MIF for antibodies to C. pneumoniae, C. trachomatis and C. psittaci and the corresponding white cells were tested for Chlamydia spp. by nPCR. Results C. pneumoniae was not detected in any carotid specimen. Twenty-five of 38 (66% plasma specimens were positive for C. pneumoniae IgG, 2/38 (5% for C. trachomatis IgG and 1/38 (3% for C. psittaci IgG. Conclusions We were unable to show an association between the presence of Chlamydia spp. and atheroma in carotid arteries in the presence of a high seroprevalence of C. pneumoniae antibodies in Northern Ireland.

  6. Membrane proteins PmpG and PmpH are major constituents of Chlamydia trachomatis L2 outer membrane complex

    DEFF Research Database (Denmark)

    Mygind, Per H; Christiansen, Gunna; Roepstorff, P;

    2000-01-01

    The outer membrane complex of Chlamydia is involved in the initial adherence and ingestion of Chlamydia by the host cell. In order to identify novel proteins in the outer membrane of Chlamydia trachomatis L2, proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis....... By silver staining of the protein profile, a major protein doublet of 100-110 kDa was detected. In-gel tryptic digestion and matrix-assisted laser desorption/ionization mass spectrometry identified these proteins as the putative outer membrane proteins PmpG and PmpH....

  7. "Rate of Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum in Infertile Females and Control Group"

    Directory of Open Access Journals (Sweden)

    N Badami

    2001-07-01

    Full Text Available Infertility in famale is one of the most important sequela of genital infection with Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum. In the present study the frequency of these bacteries was studied in 125 infertile female by direct and indirect immunofluorscence tests and culture method and compared with 250 normal population. Mycoplasma hominis was isolated from 32 (35.6% of infertile females compare with 18 (7.2% of normal population. Ureaplasma urealyticum was isolated from 41 (32.8% of infertile females compare to 48 (19.2% of normal population. Chlamydia trachomatis was detected by direct IF in 11 (8.8% of infertile and 2 (0.8% control group. The antibody titer against D-K serotypes of Chlamydia trachomatis was also measured in both groups of infertile and normal population and a positive titer of 1/16 and above was detected in 26 (20.8% of infertile cases and in 8 (3.2% of control group. The rate of Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum in case and control groups was significant (respectively P<0.0001, P<0.0001, p= 0.0018.

  8. Impact of Mass Distribution of Azithromycin on the Antibiotic Susceptibilities of Ocular Chlamydia trachomatis

    Science.gov (United States)

    Solomon, Anthony W.; Mohammed, Zeena; Massae, Patrick A.; Shao, John F.; Foster, Allen; Mabey, David C. W.; Peeling, Rosanna W.

    2005-01-01

    In a community of Tanzania where trachoma is endemic, we cultured conjunctival swabs from all residents who had active trachoma and were PCR positive for ocular Chlamydia trachomatis, both before (43 isolates) and 2 months after (9 isolates) mass antibiotic treatment. No clinically or programmatically significant increase in azithromycin or tetracycline resistance was observed. PMID:16251338

  9. Impact of Mass Distribution of Azithromycin on the Antibiotic Susceptibilities of Ocular Chlamydia trachomatis

    OpenAIRE

    Solomon, Anthony W.; Mohammed, Zeena; Massae, Patrick A.; Shao, John F.; Foster, Allen; Mabey, David C.W.; Peeling, Rosanna W

    2005-01-01

    In a community of Tanzania where trachoma is endemic, we cultured conjunctival swabs from all residents who had active trachoma and were PCR positive for ocular Chlamydia trachomatis, both before (43 isolates) and 2 months after (9 isolates) mass antibiotic treatment. No clinically or programmatically significant increase in azithromycin or tetracycline resistance was observed.

  10. Perceptions of Self-Testing for Chlamydia: Understanding and Predicting Self-Test Use

    Directory of Open Access Journals (Sweden)

    Rachael Powell

    2016-05-01

    Full Text Available Background: Self-testing technology allows people to test themselves for chlamydia without professional support. This may result in reassurance and wider access to chlamydia testing, but anxiety could occur on receipt of positive results. This study aimed to identify factors important in understanding self-testing for chlamydia outside formal screening contexts, to explore the potential impacts of self-testing on individuals, and to identify theoretical constructs to form a Framework for future research and intervention development. Methods: Eighteen university students participated in semi-structured interviews; eleven had self-tested for chlamydia. Data were analysed thematically usingaFrameworkapproach. Results: Perceivedbenefitsofself-testingincludeditsbeingconvenient, anonymousandnotrequiringphysicalexamination. Therewasconcernabouttestaccuracyandsome participants lacked confidence in using vulvo-vaginal swabs. While some participants expressed concern about the absence of professional support, all said they would seek help on receiving a positive result. Factors identified in Protection Motivation Theory and the Theory of Planned Behaviour, such as response efficacy and self-efficacy, were found to be highly salient to participants in thinking about self-testing. Conclusions: These exploratory findings suggest that self-testing independentlyofformalhealthcaresystemsmaynomorenegativelyimpactpeoplethanbeingtested by health care professionals. Participants’ perceptions about self-testing behaviour were consistent with psychological theories. Findings suggest that interventions which increase confidence in using self-tests and that provide reassurance of test accuracy may increase self-test intentions.

  11. Chlamydia trachomatis contains a protein similar to the Legionella pneumophila mip gene product

    DEFF Research Database (Denmark)

    Lundemose, AG; Birkelund, Svend; Fey, SJ;

    1991-01-01

    A 27kDa Chlamydia trachomatis L2 protein was characterized by the use of monoclonal antibodies and by two-dimensional gel electrophoresis. The protein was shown to be located in the membrane of reticulate bodies as well as elementary bodies. Its synthesis could be detected from 10 hours post-infe...... potentiator (mip) gene of Legionella pneumophila....

  12. Influence of volume of sample processed on detection of Chlamydia trachomatis in urogenital samples by PCR

    NARCIS (Netherlands)

    Goessens, W H; Kluytmans, J A; den Toom, N; van Rijsoort-Vos, T H; Niesters, B G; Stolz, E; Verbrugh, H A; Quint, W G

    1995-01-01

    In the present study, it was demonstrated that the sensitivity of the PCR for the detection of Chlamydia trachomatis is influenced by the volume of the clinical sample which is processed in the PCR. An adequate sensitivity for PCR was established by processing at least 4%, i.e., 80 microliters, of t

  13. Interleukin-1 is the initiator of fallopian tube destruction during Chlamydia trachomatis infection

    DEFF Research Database (Denmark)

    Hvid, Malene; Baczynska, Agata; Deleuran, Bent Winding;

    2007-01-01

    Chlamydia trachomatis infection is associated with severe Fallopian tube tissue damage leading to tubal infertility and ectopic pregnancy. To explore the molecular mechanisms behind infection an ex vivo model was established from human Fallopian tubes and examined by scanning electron microscopy...

  14. Chlamydia psittaci : a relevant cause of community-acquired pneumonia in two Dutch hospitals

    NARCIS (Netherlands)

    Spoorenberg, S M C; Bos, W J W; van Hannen, E J; Dijkstra, F; Heddema, E R; van Velzen-Blad, H; Heijligenberg, R; Grutters, J C; de Jongh, B M; Meijvis, SCA

    2016-01-01

    BACKGROUND: Of all hospitalised community-acquired pneumonias (CAPs) only a few are known to be caused by Chlamydia psittaci. Most likely the reported incidence, ranging from of 0% to 2.1%, is an underestimation of the real incidence, since detection of psittacosis is frequently not incorporated in

  15. Influence of volume of sample processed on detection of Chlamydia trachomatis in urogenital samples by PCR

    NARCIS (Netherlands)

    W.H.F. Goessens (Wil); J.A.J.W. Kluytmans (Jan); N. den Toom; T.H. van Rijsoort-Vos; E. Stolz (Ernst); H.A. Verbrugh (Henri); W.G.V. Quint (Wim); H.G.M. Niesters (Bert)

    1995-01-01

    textabstractIn the present study, it was demonstrated that the sensitivity of the PCR for the detection of Chlamydia trachomatis is influenced by the volume of the clinical sample which is processed in the PCR. An adequate sensitivity for PCR was established by processing at least

  16. Detection of infections of the eye with Chlamydia trachomatis by the polymerase chain reaction

    NARCIS (Netherlands)

    J. Fan (Jun); W.Y. Zhang (Wen); Y.Y. Wu (Yu); X.Y. Jing (Xiou); E.C.J. Claas (Eric)

    1993-01-01

    textabstractThe aim of this study was to test the diagnostic feasibility of the polymerase chain reaction (PCR) for detection of infections with Chlamydia trachomatis in eye swabs from patients with conjunctivitis, and to establish the basic technique of the PCR for epidemiological survey. The resul

  17. Quantitative Detection of Respiratory Chlamydia pneumoniae Infection by Real-Time PCR

    OpenAIRE

    Kuoppa, Yvonne; Boman, Jens; Scott, Lena; Kumlin, Urban; Eriksson, Iréne; Allard, Annika

    2002-01-01

    Real-time PCR was evaluated as a quantitative diagnostic method for Chlamydia pneumoniae infection using different respiratory samples. Real-time PCR had efficiency equal to or better than that of nested touchdown PCR. This study confirmed sputum as the best sampling material to detect an ongoing C. pneumoniae infection.

  18. One-tube nested Polymerase Chain Reaction for detection of Chlamydia trachomatis

    Directory of Open Access Journals (Sweden)

    Cribb Pamela

    2002-01-01

    Full Text Available Here we present a one-tube nested PCR test, which allows the detection of minimal quantities of Chlamydia trachomatis in human fluids. This assay includes the use of an internal control to avoid false negative results due to the presence of inhibitors. The results obtained show that this assay is robust enough to be used for clinical diagnosis.

  19. Chlamydia trachomatis infection during pregnancy: knowledge, test practices, and attitudes of Dutch midwives.

    NARCIS (Netherlands)

    Pereboom, M.T.R.; Manniën, J.; Rours, G.I.J.G.; Spelten, E.R.; Hutton, E.K.; Schellevis, F.G.

    2014-01-01

    Background: Chlamydia trachomatis infection in pregnancy may lead to adverse pregnancy outcomes. In the Netherlands, testing for C. trachomatis is based on risk assessment. We assessed midwives' knowledge, test practices, assessment of risk behavior, and attitudes regarding testing for C. trachomati

  20. Risk Factors for Incident and Redetected Chlamydia trachomatis Infection in Women

    DEFF Research Database (Denmark)

    Harder, Elise; Thomsen, Louise T; Frederiksen, Kirsten;

    2016-01-01

    OBJECTIVES: To investigate risk factors for incident and redetected Chlamydia trachomatis (CT) infection in women, including the role of high-risk human papillomavirus (HPV). METHODS: In this population-based, prospective cohort study conducted in Copenhagen, Denmark, 10,729 women aged 20 to 29 y...

  1. Multilocus Sequence Typing of Urogenital Chlamydia trachomatis From Patients With Different Degrees of Clinical Symptoms

    NARCIS (Netherlands)

    Christerson, L.; de Vries, H.J.C.; Klint, M.; Herrmann, B.; Morré, S.A.

    2011-01-01

    Background: In the past, contradictory results have been obtained linking Chlamydia trachomatis serovars (ompA gene) to different clinical courses of infection. Methods: A high resolution multilocus sequence typing (MLST) system was used to genotype 6 genetic regions, including ompA, in 70 Dutch uro

  2. Overexpression and surface localization of the Chlamydia trachomatis major outer membrane protein in Escherichia coli

    DEFF Research Database (Denmark)

    Koehler, JF; Birkelund, Svend; Stephens, RS

    1992-01-01

    The Chlamydia trachomatis major outer membrane protein (MOMP) is the quantitatively predominant surface protein which has important functional, structural and antigenic properties. We have cloned and overexpressed the MOMP in Escherichia coli. The MOMP is surface exposed in C. trachomatis and cap...... the contribution of the MOMP variable segments to the topographical interactions which determine the antigenic structure responsible for human immune response....

  3. Systematic screening for Chlamydia trachomatis : Estimating cost-effectiveness using dynamic modeling and Dutch data

    NARCIS (Netherlands)

    de Vries, R.; Van Bergen, J.E.A.M.; de Jong-van den Berg, Lolkje; Postma, Maarten

    2006-01-01

    To estimate the cost-effectiveness of a systematic one-off Chlamydia trachomatis (CT) screening program including partner treatment for Dutch young adults. Data on infection prevalence, participation rates, and sexual behavior were obtained from a large pilot study conducted in The Netherlands. Oppo

  4. Chlamydia trachomatis and genital human papillomavirus infections in female university students in Honduras.

    NARCIS (Netherlands)

    Tabora, N.; Zelaya, A.; Bakkers, J.; Melchers, W.J.; Ferrera, A.

    2005-01-01

    Sexually transmitted infections are a serious health problem in Honduras. Human papillomavirus (HPV) and Chlamydia trachomatis are major causes of sexually transmitted diseases. To determine the prevalence of C. trachomatis and HPV in young women, 100 female university students in Honduras were assa

  5. Cost-effectiveness analysis of Chlamydia trachomatis screening in Dutch pregnant women

    NARCIS (Netherlands)

    Rours, G I J G; Smith-Norowitz, Tamar Anne; Ditkowsky, Jared; Hammerschlag, Margaret R; Verkooyen, R P; de Groot, R.; Verbrugh, H A; Postma, Maarten

    2016-01-01

    Chlamydia trachomatis infections during pregnancy may have serious consequences for women and their offspring. Chlamydial infections are largely asymptomatic. Hence, prevention is based on screening. The objective of this study was to estimate the cost-effectiveness of C. trachomatis screening durin

  6. Cost-effectiveness analysis of Chlamydia trachomatis screening in Dutch pregnant women

    NARCIS (Netherlands)

    G.I.J.G. Rours (Ingrid); Smith-Norowitz, T.A. (Tamar Anne); Ditkowsky, J. (Jared); M.R. Hammerschlag; R.P.A.J. Verkooyen (Roel); de Groot, R.; H.A. Verbrugh (Henri); M.J. Postma (Maarten)

    2016-01-01

    textabstractChlamydia trachomatis infections during pregnancy may have serious consequences for women and their offspring. Chlamydial infections are largely asymptomatic. Hence, prevention is based on screening. The objective of this study was to estimate the cost-effectiveness of C. trachomatis scr

  7. Chlamydia species in free-living Cattle Egret (Bubulcus ibis and Hoopoe (Upupa epops in Egypt

    Directory of Open Access Journals (Sweden)

    Jakeen K. El-Jakee

    2014-06-01

    Full Text Available Little information is available on the presence of chlamydia infection in wildlife. This study was conducted to assess the occurrence of chlamydiae in asymptomatic birds from two species of wild birds (Cattle Egret and Hoopoe in Egypt. In the present study Chlamydiaceae was analyzed using Giemsa stain, Giménez stain, fluorescent antibody test (FAT and PCR. The results of these techniques were compared with CFT for detecting Chlamydia psittaci antibodies among the examined birds. The results reveal that 96.4%, 81.8%, 89.1%, 80.0% and 58.2% of the examined samples were positive for chlamydiosis using PCR, Giemsa stain, Giménez stain, FA, and CFT respectively among Hoopoe. The percentages were 90.6%, 77.4%, 83.0%, 75.5% and 66.0% respectively for the previous tests among Cattle Egret birds. The results suggest that Cattle Egret and Hoopoe may be reservoir of Chlamydiaceae species and thus shed the organisms in their excreta. The shedding of chlamydiae by free living birds in Egypt may expose humans that come in contact with these birds to zoonotic risks.

  8. Low prevalence of the new variant of Chlamydia trachomatis in Denmark

    DEFF Research Database (Denmark)

    Jensen, J.S.; Westh, Henrik T.

    2008-01-01

    We estimated the prevalence of the new variant of Chlamydia trachomatis in Denmark. Fifty consecutive C trachomatis urine samples from each of the 14 regional microbiology laboratories were initially tested and re-analysed with a real-time C trachomatis PCR assay targeting the 16S rRNA gene...

  9. [Evaluation of testicular biopsy as an aspect of Chlamydia trachomatis infection (introductory report)].

    Science.gov (United States)

    Maciejewski, Z; Swierczyński, W; Dziecielski, H; Semmler, G

    1989-01-01

    The purpose of the study was demonstration of the presence of Chlamydia trachomatis in biopsy testicular specimens. The indication to testicular biopsy was azoospermia or cryptozoospermia. The studied group comprised 12 patients in whose semen C. trachomatis was found. For the identification of the organism culture in chick embryo was used. In 2 preparations C. trachomatis was demonstrated in testicular biopsy.

  10. Waddlia chondrophila and Chlamydia trachomatis antibodies in screening infertile women for tubal pathology

    NARCIS (Netherlands)

    Verweij, S. P.; Kebbi-Beghdadi, C.; Land, J. A.; Ouburg, S.; Morre, S. A.; Greub, G.

    2015-01-01

    Since Waddlia chondrophila is closely related to Chlamydia trachomatis, we hypothesise that W. chondrophila may also be associated with tubal factor infertility (TFI) in women, a major complication of chronic C. trachomatis infection. Five hundred twenty serum samples were tested for anti-Waddlia an

  11. Immunoglobulin A antibodies against Chlamydia pneumoniae are associated with expansion of abdominal aortic aneurysm

    DEFF Research Database (Denmark)

    Lindholt, J.S; Juul, Svend; Vammen, S

    1999-01-01

    BACKGROUND: The aim of this study was to examine the possible association between the progression of small abdominal aortic aneurysm (AAA) and chronic infection with Chlamydia pneumoniae. METHODS: Patients from a hospital-based mass screening programme for AAA with annual follow-up (mean 2.7 years....... pneumoniae. Aneurysm progression correlated with evidence of chronic C. pneumoniae infection....

  12. Chlamydia trachomatis in women attending a gynaecological outpatient clinic with lower genital tract infection.

    Science.gov (United States)

    Svensson, L; Weström, L; Mårdh, P A

    1981-08-01

    In a study of 3794 consecutive women attending a gynaecological outpatient clinic with symptoms of lower genital tract infection (LGTI) 350 (9.2%) harboured Chlamydia trachomatis and 83 (2.2%) Neisseria gonorrhoeae. One hundred and ninety-five patients who were later found to have acute salpingitis and 109 other women in whom the chlamydial cultures were spoiled were excluded from the series. Of the remaining 3490 women, 281 were infected with C trachomatis, 42 with N gonorrhoeae, and 17 with both. Of the 3150 women who were infected with neither organism, 146 were randomly selected as controls. The chlamydia-positive patients were younger (P less than 0.001), did not complain of pelvic discomfort or pain (P less than 0.01), and used oral contraceptives (P less than 0.001) more frequently than did the controls; intrauterine devices were used more often (P less than 0.01) by the controls. Increased vaginal discharge was reported significantly more often in chlamydia-positive patients than in the controls (P less than 0.05). Of 266 women harbouring C trachomatis the organism was still present in 22 (8.3%) when they were followed up from two to more than eight weeks after finishing treatment with doxycycline. Of 91 male consorts of chlamydia-positive women, 53 (58.2%) were infected with C trachomatis.

  13. Sexual behavior and the prevalence of Chlamydia trachomatis infection in asymptomatic students in Germany and Spain.

    Science.gov (United States)

    Stock, C; Guillén-Grima, F; Prüfer-Krämer, L; Serrano-Monzo, I; Marin-Fernandez, B; Aguinaga-Ontoso, I; Krämer, A

    2001-01-01

    This study aimed to assess patterns of sexual activity, preventive behaviors, contraceptive use, and the prevalence of chlamydia infection in student populations from two countries. 188 asymptomatic students of the University of Bielefeld, Germany and 590 students of the Navarra Public University, Spain were surveyed using a standardized self-administered questionnaire. Urine samples were analyzed by ligase chain reaction technique for chlamydia infection. Compared to German students, Spanish students were less likely to have more than one sex partner within the last 12 months (OR: 0.62; CI: 0.46-0.83), to have sexual intercourse more than one time per week (OR: 0.70; CI: 0.52-0.93) and to use oral contraceptives (OR: 0.16; CI: 0.10-0.26). They reported a higher use of condoms (OR: 2.93; CI: 2.01-4.27) and were more likely to always use condoms with a new sex partner (OR: 2.47; CI: 1.72-3.53). The prevalence of chlamydia infection was considerably higher in German students (5.8% [corrected] in females; 2.2% in males) than in Spanish students, where no case was found. The higher frequency of sexual activity, a higher engagement in risk-taking sexual behavior and the lower use of barrier contraceptives may contribute to the higher prevalence of chlamydia infection in German students.

  14. Chlamydia gallinacea, not C. psittaci, is the endemic chlamydial species in chicken (Gallus gallus).

    Science.gov (United States)

    Guo, Weina; Li, Jing; Kaltenboeck, Bernhard; Gong, Jiansen; Fan, Weixing; Wang, Chengming

    2016-01-18

    To investigate the prevalence and diversity of Chlamydia spp. in domestic birds in China, oral and cloacal swabs of healthy chickens, ducks, geese and pigeons were collected nationwide from live-animal markets and examined by Chlamydia spp. 23 S rRNA gene FRET-PCR followed by high-resolution melting curve analysis and confirmatory sequencing. Overall, 26.2% of the birds (602/2,300) were positive for Chlamydia spp. and five Chlamydia spp. were identified. While occasional detection of C. suis and C. muridarum in poultry is reported here for the first time, the predominant chlamydial agent was C. gallinacea representing 63.8% of all positives (384/602) and 81.2% of positive chickens (359/442). Analysis of the C. gallinacea ompA phylogeny revealed at least 13 well segregated variants (serovars). Seven-month monitoring of C. gallinacea-infected chickens indicated that the infection was persistent. C. gallinacea-infected chickens remained without overt clinical disease, but showed body weight gains significantly reduced by 6.5-11.4% beginning in week 3 post-infection. This study indicates that C. gallinacea is the endemic chlamydial species in chickens, whereas C. psittaci dominates only in pigeons. Further studies are required to address the specific conditions under which C. gallinacea could act as an avian pathogen and possibly also a zoonotic agent.

  15. Lymphogranuloma venereum caused by Chlamydia trachomatis serovar L3: a case report

    Institute of Scientific and Technical Information of China (English)

    KANG Er-xun; GAO Xing; YIN Yue-ping; WANG Fu-sheng; YAO Wei-dong; GONG Xiang-qian; CHEN Xiang-sheng

    2007-01-01

    @@ Lymphogranuloma venereum (LGV) is a systemic sexually transmitted disease caused by Chlamydia trachomatis (C. trachomatis) L1, L2 and L3, the organism gains entrance through skin breaks and abrasions and travels via the lymphatics to multiply within mononuclear phagocytes in regional lymph nodes.

  16. 衣原体质粒研究进展%Progress in Research of Chlamydia Plasmid

    Institute of Scientific and Technical Information of China (English)

    彭菁; 刘良专; 吴移谋

    2013-01-01

    质粒是染色体外的遗传物质,大部分衣原体中存在隐蔽性质粒,其特有的基因组学和编码的蛋白对衣原体的生长周期、毒力、致病性和免疫性等起着十分重要的作用,对衣原体质粒的研究有助于了解其生物学作用,从而更好的预防与治疗衣原体感染的感染.%Plasmids are extrachromosomal genetic material. There are cryptic plasmids in most of Chlamydia, whose unique genomics and proteins encoded by the genomics play an important role in the growth cycle, virulence, pathogenicity and immunity of chlamydia. The studying of chlamydia plasmid is benefit of understanding their biological roles and base the prevention and treatment of Chlamydia infection.

  17. Site-specific, insertional inactivation of incA in Chlamydia trachomatis using a group II intron.

    Science.gov (United States)

    Johnson, Cayla M; Fisher, Derek J

    2013-01-01

    Chlamydia trachomatis is an obligate, intracellular bacterial pathogen that has until more recently remained recalcitrant to genetic manipulation. However, the field still remains hindered by the absence of tools to create selectable, targeted chromosomal mutations. Previous work with mobile group II introns demonstrated that they can be retargeted by altering DNA sequences within the intron's substrate recognition region to create site-specific gene insertions. This platform (marketed as TargeTron™, Sigma) has been successfully employed in a variety of bacteria. We subsequently modified TargeTron™ for use in C. trachomatis and as proof of principle used our system to insertionally inactivate incA, a chromosomal gene encoding a protein required for homotypic fusion of chlamydial inclusions. C. trachomatis incA::GII(bla) mutants were selected with ampicillin and plaque purified clones were then isolated for genotypic and phenotypic analysis. PCR, Southern blotting, and DNA sequencing verified proper GII(bla) insertion, while continuous passaging in the absence of selection demonstrated that the insertion was stable. As seen with naturally occurring IncA(-) mutants, light and immunofluorescence microscopy confirmed the presence of non-fusogenic inclusions in cells infected with the incA::GII(bla) mutants at a multiplicity of infection greater than one. Lack of IncA production by mutant clones was further confirmed by Western blotting. Ultimately, the ease of retargeting the intron, ability to select for mutants, and intron stability in the absence of selection makes this method a powerful addition to the growing chlamydial molecular toolbox.

  18. Lactobacillus crispatus mediates anti-inflammatory cytokine interleukin-10 induction in response to Chlamydia trachomatis infection in vitro.

    Science.gov (United States)

    Rizzo, Antonietta; Fiorentino, Margherita; Buommino, Elisabetta; Donnarumma, Giovanna; Losacco, Antonio; Bevilacqua, Nazario

    2015-12-01

    Chlamydia trachomatis, a human pathogen, is a Gram-negative bacillus and a compulsory intracellular parasite. It is the most common cause of bacterial sexually transmitted infections in both industrialized and developing countries. In women, untreated genital infections can result in devastating consequences such as pelvic inflammatory disease, ectopic pregnancy, and even infertility. Lactobacillus crispatus is an important urogenital species that is routinely found in the vagina of healthy women. Lactobacilli are involved in the maintenance of the normal vaginal microbiota and their dominance in the vagina suggests that they play a crucial role in protecting the genitourinary tract against pathological conditions. Lactobacilli can act through the activation of the immune system, but C. trachomatis is able to effectively evade immune surveillance in some individuals. The aim of our study was to investigate the immunomodulatory efficacy of the potential probiotic strain L. crispatus in HeLa and J774 cells subjected to C. trachomatis infection by studying the expression of the inflammatory cytokines IL-6, IL-8, TNF-α and IL-10. Our results demonstrated, firstly, the lack of any cytotoxic effect on the epithelial cells and macrophages when treated with L. crispatus and its supernatant; in addition, L. crispatus and its supernatant inhibited C. trachomatis adhesion and infectivity in human epithelial cells and macrophages. Our study then showed that L. crispatus and its supernatant reduced IL-6, IL-8 and TNF-α production in C. trachomatis-infected HeLa and J774 cells. In contrast, a significant upregulation of the IL-10 expression in HeLa and J774 cells by L. crispatus and supernatant was also demonstrated. Our data indicate that L. crispatus specifically enhances the production of the IL-10 anti-inflammatory cytokine in contrast to the inhibitory effect of L. crispatus on the pro-inflammatory cytokines.

  19. Characterization of serine hydroxymethyltransferase GlyA as a potential source of D-alanine in Chlamydia pneumoniae

    Directory of Open Access Journals (Sweden)

    Stefania eDe Benedetti

    2014-02-01

    Full Text Available For intracellular Chlamydiaceae, there is no need to withstand osmotic challenges, and a functional cell wall has not been detected in these pathogens so far. Nevertheless, penicillin inhibits cell division in Chlamydiaceae resulting in enlarged aberrant bodies, a phenomenon known as chlamydial anomaly.D-alanine is a unique and essential component in the biosynthesis of bacterial cell walls. In free-living bacteria like Escherichia coli, penicillin-binding proteins such as monofunctional transpeptidases PBP2 and PBP3, the putative targets of penicillin in Chlamydiaceae, cross-link adjacent peptidoglycan strands via meso-diaminopimelic acid and D-Ala-D-Ala moieties of pentapeptide side chains. In the absence of genes coding for alanine racemase Alr and DadX homologs, the source of D-Ala and thus the presence of substrates for PBP2 and PBP3 activity in Chlamydiaceae has puzzled researchers for years. Interestingly, Chlamydiaceae genomes encode GlyA, a serine hydroxymethyltransferase that has been shown to exhibit slow racemization of D- and L- alanine as a side reaction in E. coli. We show that GlyA from Chlamydia pneumoniae can serve as a source of D-Ala. GlyA partially reversed the D-Ala auxotrophic phenotype of an E. coli racemase double mutant. Moreover, purified chlamydial GlyA had racemase activity on L-Ala in vitro and was inhibited by D-cycloserine, identifying GlyA, besides D-Ala ligase MurC/Ddl, as an additional target of this competitive inhibitor in Chlamydiaceae. Proof of D-Ala biosynthesis in Chlamydiaceae helps to clarify the structure of cell wall precursor lipid II and the role of chlamydial penicillin-binding proteins in the development of non-dividing aberrant chlamydial bodies and persistence in the presence of penicillin.

  20. Staff views of an opportunistic chlamydia testing pilot in a primary health organisation

    Directory of Open Access Journals (Sweden)

    McKernon S

    2013-12-01

    Full Text Available INTRODUCTION: The Auckland chlamydia pilot was one of three pilots funded by the Ministry of Health to trial implementation of the 2008 Chlamydia Management Guidelines prior to national roll-out. AIM: To assess what elements in the testing programme pilot worked best for staff and to determine how an opportunistic testing programme could be better configured to meet staff needs and preferences. METHODS: A staff survey listed key chlamydia testing tasks in chronological order, and service interventions supporting these tasks. Staff were asked to rate each task on its difficulty prior to the pilot, and then on the difference the pilot had made to each task. They were also asked to rate service interventions on their usefulness during the pilot implementation. RESULTS: The survey had a response rate of 94%. The testing tasks posing the greatest difficulties to staff were those involving patient interactions (41% and management of follow-up (52%. About 70% of staff felt tasks were improved by the pilot. Staff considered the three most useful service interventions to be a chlamydia-specific template created for the practice management system, provision of printed patient resources, and regular team discussions with other staff. DISCUSSION: A significant proportion of staff reported difficulties with routine tasks required for opportunistic testing for chlamydia, highlighting the need to involve staff during programme design. Practice nurse-led approaches to future opportunistic testing programmes should be considered as nurses had a more positive response to the pilot and nurse-led approaches have been shown to be successful overseas.

  1. Effects of population based screening for Chlamydia infections in the Netherlands limited by declining participation rates.

    Directory of Open Access Journals (Sweden)

    Boris V Schmid

    Full Text Available BACKGROUND: A large trial to investigate the effectiveness of population based screening for chlamydia infections was conducted in the Netherlands in 2008-2012. The trial was register based and consisted of four rounds of screening of women and men in the age groups 16-29 years in three regions in the Netherlands. Data were collected on participation rates and positivity rates per round. A modeling study was conducted to project screening effects for various screening strategies into the future. METHODS AND FINDINGS: We used a stochastic network simulation model incorporating partnership formation and dissolution, aging and a sexual life course perspective. Trends in baseline rates of chlamydia testing and treatment were used to describe the epidemiological situation before the start of the screening program. Data on participation rates was used to describe screening uptake in rural and urban areas. Simulations were used to project the effectiveness of screening on chlamydia prevalence for a time period of 10 years. In addition, we tested alternative screening strategies, such as including only women, targeting different age groups, and biennial screening. Screening reduced prevalence by about 1% in the first two screening rounds and leveled off after that. Extrapolating observed participation rates into the future indicated very low participation in the long run. Alternative strategies only marginally changed the effectiveness of screening. Higher participation rates as originally foreseen in the program would have succeeded in reducing chlamydia prevalence to very low levels in the long run. CONCLUSIONS: Decreasing participation rates over time profoundly impact the effectiveness of population based screening for chlamydia infections. Using data from several consecutive rounds of screening in a simulation model enabled us to assess the future effectiveness of screening on prevalence. If participation rates cannot be kept at a sufficient level

  2. Identification and Partial Characterization of Potential FtsL and FtsQ Homologs of Chlamydia

    Directory of Open Access Journals (Sweden)

    Scot P Ouellette

    2015-11-01

    Full Text Available Chlamydia is amongst the rare bacteria that lack the critical cell division protein FtsZ. By annotation, Chlamydia also lacks several other essential cell division proteins including the FtsLBQ complex that links the early (e.g. FtsZ and late (e.g. FtsI/Pbp3 components of the division machinery. Here, we report chlamydial FtsL and FtsQ homologs. Ct271 aligned well with E. coli FtsL and shared sequence homology with it, including a predicted leucine-zipper like motif. Based on in silico modeling, we show that Ct764 has structural homology to FtsQ in spite of little sequence similarity. Importantly, ct271/ftsL and ct764/ftsQ are present within all sequenced chlamydial genomes and are expressed during the replicative phase of the chlamydial developmental cycle, two key characteristics for a chlamydial cell division gene. GFP-Ct764 localized to the division septum of dividing transformed chlamydiae, and, importantly, over-expression inhibited chlamydial development. Using a bacterial two-hybrid approach, we show that Ct764 interacted with other components of the chlamydial division apparatus. However, Ct764 was not capable of complementing an E. coli FtsQ depletion strain in spite of its ability to interact with many of the same division proteins as E. coli FtsQ, suggesting that chlamydial FtsQ may function differently. We previously proposed that Chlamydia uses MreB and other rod-shape determining proteins as an alternative system for organizing the division site and its apparatus. Chlamydial FtsL and FtsQ homologs expand the number of identified chlamydial cell division proteins and suggest that Chlamydia has likely kept the late components of the division machinery while substituting the Mre system for the early components.

  3. Characterisation of Chlamydia pneumoniae and other novel chlamydial infections in captive snakes.

    Science.gov (United States)

    Taylor-Brown, Alyce; Rüegg, Simon; Polkinghorne, Adam; Borel, Nicole

    2015-07-01

    Chlamydiosis has been described in both free-ranging and captive reptiles. The infection usually manifests as granulomatous inflammation in inner organs such as spleen, heart, lung and liver but might also occur in asymptomatic reptiles. The aim of this study was to investigate and characterise Chlamydia pneumoniae and potential other novel chlamydial infections in the choana and cloaca samples of 137 clinically healthy captive snakes from six private collections. Forty eight samples from 29 animals were found to be positive by a Chlamydiaceae family-specific qPCR. By Chlamydia species-specific ArrayTube Microarray, 43 samples were positive, with 36 of these being identified as C. pneumoniae. The prevalence of Chlamydia ranged from 5 to 33%. PCR and sequencing of the Chlamydiales 16S rRNA signature sequence of 21 Chlamydia positive samples revealed the presence of seven novel 16S rRNA genotypes. BLAST-n and phylogenetic analysis of the near-full length 16S rRNA gene sequence of each of these novel 16S rRNA sequences revealed that five genotypes share closest sequence identity to 16S rRNA sequences from C. pneumoniae (98.6-99.2%), suggesting that these sequences are novel C. pneumoniae strains. One genotype is 96.9% similar to C. pneumoniae strains suggesting it may originate from a yet undescribed chlamydial species within the genus Chlamydia. This study further highlights the broad host range for C. pneumoniae and suggests that reptiles may still contain a significant and largely uncharacterised level of chlamydial genetic diversity that requires further investigation.

  4. Chlamydia muridarum infection subverts dendritic cell function to promote Th2 immunity and airways hyperreactivity.

    Science.gov (United States)

    Kaiko, Gerard E; Phipps, Simon; Hickey, Danica K; Lam, Chuan En; Hansbro, Philip M; Foster, Paul S; Beagley, Kenneth W

    2008-02-15

    There is strong epidemiological evidence that Chlamydia infection can lead to exacerbation of asthma. However, the mechanism(s) whereby chlamydial infection, which normally elicits a strong Th type 1 (Th1) immune response, can exacerbate asthma, a disease characterized by dominant Th type 2 (Th2) immune responses, remains unclear. In the present study, we show that Chlamydia muridarum infection of murine bone marrow-derived dendritic cells (BMDC) modulates the phenotype, cytokine secretion profile, and Ag-presenting capability of these BMDC. Chlamydia-infected BMDC express lower levels of CD80 and increased CD86 compared with noninfected BMDC. When infected with Chlamydia, BMDC secrete increased TNF-alpha, IL-6, IL-10, IL-12, and IL-13. OVA peptide-pulsed infected BMDC induced significant proliferation of transgenic CD4(+) DO11.10 (D10) T cells, strongly inhibited IFN-gamma secretion by D10 cells, and promoted a Th2 phenotype. Intratracheal transfer of infected, but not control noninfected, OVA peptide-pulsed BMDC to naive BALB/c mice, which had been i.v. infused with naive D10 T cells, resulted in increased levels of IL-10 and IL-13 in bronchoalveolar lavage fluid. Recipients of these infected BMDC showed significant increases in airways resistance and decreased airways compliance compared with mice that had received noninfected BMDC, indicative of the development of airways hyperreactivity. Collectively, these data suggest that Chlamydia infection of DCs allows the pathogen to deviate the induced immune response from a protective Th1 to a nonprotective Th2 response that could permit ongoing chronic infection. In the setting of allergic airways inflammation, this infection may then contribute to exacerbation of the asthmatic phenotype.

  5. Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque: a prospective study Chlamydia pneumoniae e placa aterosclerótica sintomática de carótida: um estudo prospectivo

    Directory of Open Access Journals (Sweden)

    Rubens J. Gagliardi

    2007-06-01

    Full Text Available OBJECTIVE: To investigate the possible link between symptomatic carotid atherosclerotic plaque and Chlamydia pneumoniae. BACKGROUND: Recently, several studies have demonstrated that there may be a possible link between Chlamydia pneumonia and carotid atherosclerosis, however the real role of Chlamydia pneumoniae is not completely understood. METHOD: This is a prospective study with a total of 52 patients analyzed. All patients had been submitted to endarterectomy, and had suffered thrombotic ischemic stroke or transient ischemic attack up to 60 days prior to the surgery. Every patient presented carotid stenosis over 70%. The plaque was removed during the surgery and the laboratory exams were immediately done. Evaluation of Chlamydia pneumoniae DNA was done using polymerase chain reaction (PCR. RESULTS: The PCR analyses of all 52 patients were negative for Chlamydia pneumoniae. CONCLUSION: These initial results do not show a relationship between Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque.OBJETIVO: Investigar a possível relação entre placa sintomática de carótidas e Chlamydia pneumoniae. INTRODUÇÃO: Vários estudos têm demonstrado uma possível relação entre Chlamydia pneumonia e aterosclerose carotídea, entretanto o papel definitivo da bactéria não é totalmente conhecido. Há muita especulação: poderia iniciar o processo aterosclerótico, agravá-lo ou desestabilizá-lo. MÉTODO: Estudo prospectivo com um total de 52 pacientes, endarterectomizados e previamente acometidos de acidente vascular cerebral isquêmico ou crise isquêmica transitória, em até 60 dias antes da cirurgia. Todos os pacientes apresentavam estenose carotídea superior a 70%. Os testes laboratoriais foram realizados imediatamente após a endarterectomia. A Chlamydia pneumoniae foi pesquisada através de exame de DNA com reação de polimerização em cadeia (PCR. RESULTADOS: O PCR dos 52 pacientes foram negativos para Chlamydia

  6. Hydrophilic fluorescent nanogel thermometer for intracellular thermometry.

    Science.gov (United States)

    Gota, Chie; Okabe, Kohki; Funatsu, Takashi; Harada, Yoshie; Uchiyama, Seiichi

    2009-03-01

    The first methodology to measure intracellular temperature is described. A highly hydrophilic fluorescent nanogel thermometer developed for this purpose stays in the cytoplasm and emits stronger fluorescence at a higher temperature. Thus, intracellular temperature variations associated with biological processes can be monitored by this novel thermometer with a temperature resolution of better than 0.5 degrees C.

  7. Sensitivities of PCR, MicroTrak, ChlamydiaEIA, IDEIA, and PACE 2 for purified Chlamydia trachomatis elementary bodies in urine, peripheral blood, peripheral blood leukocytes, and synovial fluid.

    OpenAIRE

    Kuipers, J G; Scharmann, K; Wollenhaupt, J; Nettelnbreker, E; Hopf, S.; Zeidler, H

    1995-01-01

    Routine microbiological diagnosis of Chlamydia-induced reactive arthritis is based mainly on the detection of Chlamydia trachomatis with urogenital swabs or in urine. Because chlamydial antigen, rRNA, and DNA are present in low quantities in the inflamed joint, highly sensitive assays are needed to detect C. trachomatis not only at the primary site of infection but also in peripheral blood and peripheral blood leukocytes, which are suspected carriers for dissemination, and in synovial fluid. ...

  8. Risk factors associated with chlamydia and gonorrhoea infection among female sex workers in two Mexico-USA border cities.

    Science.gov (United States)

    Loza, O; Strathdee, S A; Martinez, G A; Lozada, R; Ojeda, V D; Staines-Orozco, H; Patterson, T L

    2010-07-01

    Female sex workers (FSWs) aged ≥18 years without known HIV infection living in Tijuana and Ciudad Juarez, Mexico who had recent unprotected sex with clients underwent interviews and testing for chlamydia and gonorrhoea using nucleic acid amplification. Correlates of each infection were identified with logistic regression. Among 798 FSWs, prevalence of chlamydia and gonorrhoea was 13.0% and 6.4%, respectively. Factors independently associated with chlamydia were younger age, working in Tijuana versus Ciudad Juarez and recent methamphetamine injection. Factors independently associated with gonorrhoea were working in Tijuana versus Ciudad Juarez, using illegal drugs before or during sex, and having a recent male partner who injects drugs. Chlamydia and gonorrhoea infection were more closely associated with FSWs' drug use behaviours and that of their sexual partners than with sexual behaviours. Prevention should focus on subgroups of FSWs and their partners who use methamphetamine and who inject drugs.

  9. Chlamydia detection during the menstrual cycle: a cross-sectional study of women attending a sexual health service.

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    Dana S Forcey

    Full Text Available BACKGROUND: We investigated the detection of chlamydia at different stages of the menstrual cycle. METHODS: Electronic medical records for women attending Melbourne Sexual Health Centre between March 2011 and 31(st December 2012, who were tested for chlamydia by nucleic acid amplification of high vaginal, cervical, or urinary samples, and who recorded a date of last normal menstrual period (LNMP between 0-28 days were included in the analysis. Logistic regression was used to calculate adjusted odds ratio (aOR and 95% confidence intervals (CI for the association of chlamydia with menstrual cycle adjusted by demographics and behavioural variables. Chlamydia and beta globin load were determined on those with stored samples. RESULTS: Of the 10,017 consultations that included a test for chlamydia and a valid LNMP, there were 417 in which chlamydia was detected. The proportion of samples with chlamydia was greater in the luteal phase (4.8%, 184/3831 than in the follicular phase (3.4%, 233/6816 both in the crude (OR 1.29 95%CI 1.1-1.6, p = 0.01 and adjusted odds ratio (aOR 1.4 (95%CI 1.1-1.8, p = 0.004. Among women using hormonal contraception, there was no significant association with the luteal phase of the menstrual cycle (aOR 1.3, 95%CI 0.9, 1.8, p = 0.18. Among women not using hormonal contraception, there was a significant association with the luteal phase (aOR 1.6, (95% CI 1.1-2.3, p = 0.007. The chlamydia load was not significantly different in the 329 positive stored samples in weeks 3 and 4 vs weeks 1 and 2 for any site (P>0.12. CONCLUSIONS: The higher detection of chlamydia detection in the luteal phase of the menstrual cycle in only those not taking hormonal contraception suggest that hormonal factors influence chlamydia detection. The absence of a significantly highly chlamydia load in women during the luteal phase raises questions about the mechanism.

  10. Intracellular structure and nucleocytoplasmic transport.

    Science.gov (United States)

    Agutter, P S

    1995-01-01

    Intracellular movement of any solute or particle accords with one of two general schemes: either it takes place predominantly in the solution phase or it occurs by dynamic interactions with solid-state structures. If nucleocytoplasmic exchanges of macromolecules and complexes are predominantly solution-phase processes, i.e., if the former ("diffusionist") perspective applies, then the only significant structures in nucleocytoplasmic transport are the pore complexes. However, if such exchanges accord with the latter ("solid-state") perspective, then the roles of the nucleoskeleton and cytoskeleton in nucleocytoplasmic transport are potentially, at least, as important as that of the pore complexes. The role of the nucleoskeleton in mRNA transport is more difficult to evaluate than that of the cytoskeleton because it is less well characterized, and current evidence does not exclude either perspective. However, the balance of evidence favors a solid-state scheme. It is argued that ribosomal subunits are also more likely to migrate by a solid-state rather than a diffusionist mechanism, though the opposite is true of proteins and tRNAs. Moreover, recent data on the effects of viral proteins on intranuclear RNA processing and migration accord with the solid-state perspective. In view of this balance of evidence, three possible solid-state mechanisms for nucleocytoplasmic mRNA transport are described and evaluated. The explanatory advantage of solid-state models is contrasted with the heuristic advantage of diffusion theory, but it is argued that diffusion theory itself, even aided by modern computational techniques and numerical and graphical approaches, cannot account for data describing the movements of materials within the cell. Therefore, the mechanisms envisaged in a diffusionist perspective cannot be confined to diffusion alone, but must include other processes such as bulk fluid flow.

  11. Delivery of chlamydia screening to young women requesting emergency hormonal contraception at pharmacies in Manchester, UK: a prospective study

    Directory of Open Access Journals (Sweden)

    O'Brien Karen

    2009-03-01

    Full Text Available Abstract Background More women are requesting Emergency Hormonal Contraception (EHC at pharmacies where screening for Chlamydia trachomatis is not routinely offered. The objective of this study was to assess the uptake of free postal chlamydia screening by women under 25 years who requested EHC at pharmacies in Manchester, UK. Methods Six Primary Care Trusts (PCTs that had contracted with pharmacies to provide free EHC, requested the largest EHC providers (≥ 40 doses annually to also offer these clients a coded chlamydia home testing kit. Pharmacies kept records of the ages and numbers of women who accepted or refused chlamydia kits. Women sent urine samples directly to the laboratory for testing and positive cases were notified. Audit data on EHC coverage was obtained from PCTs to assess the proportion of clients eligible for screening and to verify the uptake rate. Results 33 pharmacies participated. Audit data for 131 pharmacy months indicated that only 24.8% (675/2718 of women provided EHC were also offered chlamydia screening. Based on tracking forms provided by pharmacies for the whole of the study, 1348/2904 EHC clients (46.4% who had been offered screening accepted a screening kit. 264 (17.6% of those who accepted a kit returned a sample, of whom 24 (9.1% were chlamydia-positive. There was an increase in chlamydia positivity with age (OR: 1.2 per year; 1.04 to 1.44; p = 0.015. Conclusion Chlamydia screening for EHC pharmacy clients is warranted but failure of pharmacists to target all EHC clients represented a missed opportunity for treating a well defined high-risk group.

  12. Improving the prevention of sexually transmitted infections (STIs) : a study using Chlamydia trachomatis as a model infection

    OpenAIRE

    Novak, Daniel

    2006-01-01

    Despite the current preventive strategies sexually transmitted infections (STIs) are rising. This thesis presents a model with the aim of improving the prevention of STIs. Chlamydia being the most common STI in Sweden serves as a model infection. The presented model is based on five performed studies. First we evaluated the feasibility of taking a urine sample at home and sending it with mail for Chlamydia analysis. Postal screening was thereafter analyzed for cost effectiveness estimating th...

  13. Intracellular activity of the peptide antibiotic NZ2114: studies with Staphylococcus aureus and human THP-1 monocytes, and comparison with daptomycin and vancomycin

    DEFF Research Database (Denmark)

    Brinch, Karoline Sidelmann; Tulkens, Paul M; Van Bambeke, Francoise;

    2010-01-01

    Staphylococcus aureus survives inside eukaryotic cells. Our objective was to assess the activity of NZ2114, a novel peptidic antibiotic, against intracellular S. aureus in comparison with established antistaphylococcal agents acting on the bacterial envelope with a distinct mechanism.......Staphylococcus aureus survives inside eukaryotic cells. Our objective was to assess the activity of NZ2114, a novel peptidic antibiotic, against intracellular S. aureus in comparison with established antistaphylococcal agents acting on the bacterial envelope with a distinct mechanism....

  14. Chlamydia trachomatis infection and sexual behaviour among female students attending higher education in the Republic of Ireland

    OpenAIRE

    Vellinga Akke; O'Donovan Diarmuid; Glacken Marita; Cormican Martin; Brennan Wendy; O'Connell Emer; Cahill Niall; Lysaght Fionnguala; O'Donnell Joan

    2009-01-01

    Abstract Background There are no prevalence data on Chlamydia trachomatis relating to female students attending higher education available for the Republic of Ireland. This information is required to guide on the necessity for Chlamydia screening programmes in higher education settings. This research aimed to determine the prevalence of and predictive risk factors for Chlamydia trachomatis genital infection among female higher education students in Ireland. Methods All females presenting duri...

  15. Seroevidence of Chlamydia Trachomatis Antibody in Infertile Women in University of Benin Teaching Hospital (Ubth Benin City, Nigeria

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    Ibadin, K. O.

    2010-01-01

    Full Text Available The role of Chlamydia trachomatis in the pathogenesis of Pelvic inflammatory disease and majority of cases of salpinigitis are well acknowledged in women. A total of 213 sera from infertile women were tested for antibodies to Chlamydia trachomatis by using an indirect solid phases enzyme Immuno absorbent commercial ELISA test. Women with confirmed Hysterosalpinographic report suggesting tubal occlusion (tubal factor infertility had 92 (43.2% followed by 63 (29.6% infertile women with infertile male partner and 58 (27.2% were having unexplained infertility. Out of the tubal factor (TF infertile women 40 (18.8% were seropositive for Chlamydia trachomatis antibodies, as against 19 (8.9% in the group of women with normal patent tubes and 10 (4.6% women with infertile male partner. In this study there was a statistical significant correlation between the infertile women with tubal factor infertility in relation to seroevidence of Chlamydia trachomatis infection with p<0.05. There was no age bias in the serodetection of Chlamydia trachomatis antibodies. The seropositivity of Chlamydia trachomatis is an indication that the organism may be an independent risk factor in the development of an inflammatory process leading to scaring of the uterine tubes in women and thereby causing infertility.

  16. Comparison of Levels of Antibodies against Chlamydia Trachomatis in Infertile Women Due to Tubal Factors and Fertile Women

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    F Ghalmbor

    2009-01-01

    Full Text Available Introduction: Chlamydia trachomatis infection is a common pathogen in sexual transmitted disease, but most of female patients with this infection are asymptomatic. Sequealae include pelvic inflammatory disease, infertility and ectopic pregnancy. The aim of the study was to determine the association between Chlamydia trachomatis and tubal factor infertility, if significant. Methods: This prospective, case -control study was done in April 2005-April2006. The study group consisted of 125 patients with tubal factor infertility and the control group included 125 fertile women. The level of antibodies to Chlamydia trachomatis was determined in both groups by ELIZA method. Results: Antibody to Chlamydia trachomatis was present in 29 women in the study group (23.2% and in15 women in the control group ( 12%, respectively, (P< 0.005. The mean level of antibody in both groups was 0.76 and 0.49, respectively (P<0.0005. Conclusion: The study showed that the level of antibody against Chlamydia is significantly more in tubal factor infertile women. We therefore suggest the screening of Chlamydia antibody testing is necessary for tubal factor infertility workup.

  17. Pilot prevalence evaluation of Chlamydia Trachomatis by PCR in female infertile referred to study center of infertility in Mashhad

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    Lana Goshayeshi

    2015-04-01

    Full Text Available Background: Chlamydia trachomatis is one of the most common diseases as sexually transferred in world. According to the World Health Organization statistics, approximately 92 million new Chlamydia trachomatis infection occur in the world. Chlamydia trachomatis (CT is the cause of tubal obstruction, ectopic pregnancy and infertility in women. The aim of this study is prevalence evaluation of Chlamydia Trachomatis by PCR in female infertile referred to Montasarieh study center of infertility in Mashhad. Materials and Methods: The cervical swab specimens were collected from 100 infertile (as case and 30 fertile (as control group women attending to the infertility center of Mash-had Medical University. DNA extraction was performed from clinical specimens using DNA extraction kit. In this study, in addition to PCR reaction by commercial kit, PCR test was performed using specific primers and probe for CTCP gene. Results: The results of PCR reaction using the kit was match with PCR test and showed that the prevalence of Chlamydia trachomatis is 21% in infertile women and 3.3% in normal fertile women that was statistically significant (p=0.024. Conclusion: Considering the high sensitivity of PCR method for diagnosis of Chlamydia trachomatis infection, this method can be useful for routine screening.

  18. Monitoring county-level chlamydia incidence in Texas, 2004 – 2005: application of empirical Bayesian smoothing and Exploratory Spatial Data Analysis (ESDA) methods

    Science.gov (United States)

    Owusu-Edusei, Kwame; Owens, Chantelle J

    2009-01-01

    Background Chlamydia continues to be the most prevalent disease in the United States. Effective spatial monitoring of chlamydia incidence is important for successful implementation of control and prevention programs. The objective of this study is to apply Bayesian smoothing and exploratory spatial data analysis (ESDA) methods to monitor Texas county-level chlamydia incidence rates by examining spatiotemporal patterns. We used county-level data on chlamydia incidence (for all ages, gender and races) from the National Electronic Telecommunications System for Surveillance (NETSS) for 2004 and 2005. Results Bayesian-smoothed chlamydia incidence rates were spatially dependent both in levels and in relative changes. Erath county had significantly (p 300 cases per 100,000 residents) than its contiguous neighbors (195 or less) in both years. Gaines county experienced the highest relative increase in smoothed rates (173% – 139 to 379). The relative change in smoothed chlamydia rates in Newton county was significantly (p < 0.05) higher than its contiguous neighbors. Conclusion Bayesian smoothing and ESDA methods can assist programs in using chlamydia surveillance data to identify outliers, as well as relevant changes in chlamydia incidence in specific geographic units. Secondly, it may also indirectly help in assessing existing differences and changes in chlamydia surveillance systems over time. PMID:19245686

  19. Monitoring county-level chlamydia incidence in Texas, 2004 – 2005: application of empirical Bayesian smoothing and Exploratory Spatial Data Analysis (ESDA methods

    Directory of Open Access Journals (Sweden)

    Owens Chantelle J

    2009-02-01

    Full Text Available Abstract Background Chlamydia continues to be the most prevalent disease in the United States. Effective spatial monitoring of chlamydia incidence is important for successful implementation of control and prevention programs. The objective of this study is to apply Bayesian smoothing and exploratory spatial data analysis (ESDA methods to monitor Texas county-level chlamydia incidence rates by examining spatiotemporal patterns. We used county-level data on chlamydia incidence (for all ages, gender and races from the National Electronic Telecommunications System for Surveillance (NETSS for 2004 and 2005. Results Bayesian-smoothed chlamydia incidence rates were spatially dependent both in levels and in relative changes. Erath county had significantly (p 300 cases per 100,000 residents than its contiguous neighbors (195 or less in both years. Gaines county experienced the highest relative increase in smoothed rates (173% – 139 to 379. The relative change in smoothed chlamydia rates in Newton county was significantly (p Conclusion Bayesian smoothing and ESDA methods can assist programs in using chlamydia surveillance data to identify outliers, as well as relevant changes in chlamydia incidence in specific geographic units. Secondly, it may also indirectly help in assessing existing differences and changes in chlamydia surveillance systems over time.

  20. Stochastic resonance in an intracellular genetic perceptron

    Science.gov (United States)

    Bates, Russell; Blyuss, Oleg; Zaikin, Alexey

    2014-03-01

    Intracellular genetic networks are more intelligent than was first assumed due to their ability to learn. One of the manifestations of this intelligence is the ability to learn associations of two stimuli within gene-regulating circuitry: Hebbian-type learning within the cellular life. However, gene expression is an intrinsically noisy process; hence, we investigate the effect of intrinsic and extrinsic noise on this kind of intracellular intelligence. We report a stochastic resonance in an intracellular associative genetic perceptron, a noise-induced phenomenon, which manifests itself in noise-induced increase of response in efficiency after the learning event under the conditions of optimal stochasticity.

  1. Tuberculosis and the risk of infection with other intracellular bacteria: a population-based study.

    Science.gov (United States)

    Huaman, M A; Fiske, C T; Jones, T F; Warkentin, J; Shepherd, B E; Ingram, L A; Maruri, F; Sterling, T R

    2015-04-01

    SUMMARY Persons who develop tuberculosis (TB) may have subtle immune defects that could predispose to other intracellular bacterial infections (ICBIs). We obtained data on TB and five ICBIs (Chlamydia trachomatis, Salmonella spp., Shigella spp., Yersinia spp., Listeria monocytogenes) reported to the Tennessee Department of Health, USA, 2000-2011. Incidence rate ratios (IRRs) comparing ICBIs in persons who developed TB and ICBIs in the Tennessee population, adjusted for age, sex, race and ethnicity were estimated. IRRs were not significantly elevated for all ICBIs combined [IRR 0.87, 95% confidence interval (CI) 0.71-1.06]. C. trachomatis rate was lowest in the year post-TB diagnosis (IRR 0.17, 95% CI 0.04-0.70). More Salmonella infections occurred in extrapulmonary TB compared to pulmonary TB patients (IRR 14.3, 95% CI 1.67-122); however, this appeared to be related to HIV co-infection. TB was not associated with an increased risk of other ICBIs. In fact, fewer C. trachomatis infections occurred after recent TB diagnosis. Reasons for this association, including reduced exposure, protection conferred by anti-TB drugs or macrophage activation by Mycobacterium tuberculosis infection warrant further investigation.

  2. The prevalence and identity of Chlamydia-specific IgE in children with asthma and other chronic respiratory symptoms

    Directory of Open Access Journals (Sweden)

    Patel Katir K

    2012-04-01

    Full Text Available Abstract Background Recent studies have confirmed the presence of viable Chlamydia in the bronchoalveolar lavage (BAL fluid of pediatric patients with airway hyperresponsiveness. While specific IgG and IgM responses to C. pneumoniae are well described, the response and potential contribution of Ag-specific IgE are not known. The current study sought to determine if infection with Chlamydia triggers the production of pathogen-specific IgE in children with chronic respiratory diseases which might contribute to inflammation and pathology. Methods We obtained BAL fluid and serum from pediatric respiratory disease patients who were generally unresponsive to corticosteroid treatment as well as sera from age-matched control patients who saw their doctor for wellness checkups. Chlamydia-specific IgE was isolated from BAL and serum samples and their specificity determined by Western blot techniques. The presence of Chlamydia was confirmed by species-specific PCR and BAL culture assays. Results Chlamydial DNA was detected in the BAL fluid of 134/197 (68% patients. Total IgE increased with age until 15 years old and then decreased. Chlamydia-specific IgE was detected in the serum and/or BAL of 107/197 (54% patients suffering from chronic respiratory disease, but in none of the 35 healthy control sera (p p = 0.0001 tested positive for Chlamydia-specific IgE. Asthmatic patients had significantly higher IgE levels compared to non-asthmatics (p = 0.0001. Patients who were positive for Chlamydia DNA or culture had significantly higher levels of serum IgE compared to negative patients (p = 0.0071 and p = 0.0001 respectively. Only 6 chlamydial antigens induced Chlamydia-specific IgE and patients with C. pneumoniae-specific IgE had significantly greater levels of total IgE compared to C. pneumoniae-specific IgE negative ones (p = 0.0001. Conclusions IgE antibodies play a central role in allergic inflammation; therefore production of Chlamydia

  3. Host adaptation of Chlamydia pecorum towards low virulence evident in co-evolution of the ompA, incA, and ORF663 Loci.

    Science.gov (United States)

    Mohamad, Khalil Yousef; Kaltenboeck, Bernhard; Rahman, Kh Shamsur; Magnino, Simone; Sachse, Konrad; Rodolakis, Annie

    2014-01-01

    Chlamydia (C.) pecorum, an obligate intracellular bacterium, may cause severe diseases in ruminants, swine and koalas, although asymptomatic infections are the norm. Recently, we identified genetic polymorphisms in the ompA, incA and ORF663 genes that potentially differentiate between high-virulence C. pecorum isolates from diseased animals and low-virulence isolates from asymptomatic animals. Here, we expand these findings by including additional ruminant, swine, and koala strains. Coding tandem repeats (CTRs) at the incA locus encoded a variable number of repeats of APA or AGA amino acid motifs. Addition of any non-APA/AGA repeat motif, such as APEVPA, APAVPA, APE, or APAPE, associated with low virulence (PincA CTRs (P = 0.0028). In ORF663, high numbers of 15-mer CTRs correlated with low virulence (P = 0.0001). Correction for ompA phylogram position in ORF663 and incA abolished the correlation between genetic changes and virulence, demonstrating co-evolution of ompA, incA, and ORF663 towards low virulence. Pairwise divergence of ompA, incA, and ORF663 among isolates from healthy animals was significantly higher than among strains isolated from diseased animals (P≤10-5), confirming the longer evolutionary path traversed by low-virulence strains. All three markers combined identified 43 unique strains and 4 pairs of identical strains among all 57 isolates tested, demonstrating the suitability of these markers for epidemiological investigations.

  4. The E2-like conjugation enzyme Atg3 promotes binding of IRG and Gbp proteins to Chlamydia- and Toxoplasma-containing vacuoles and host resistance.

    Directory of Open Access Journals (Sweden)

    Arun K Haldar

    Full Text Available Cell-autonomous immunity to the bacterial pathogen Chlamydia trachomatis and the protozoan pathogen Toxoplasma gondii is controlled by two families of Interferon (IFN-inducible GTPases: Immunity Related GTPases (IRGs and Guanylate binding proteins (Gbps. Members of these two GTPase families associate with pathogen-containing vacuoles (PVs and solicit antimicrobial resistance pathways specifically to the intracellular site of infection. The proper delivery of IRG and Gbp proteins to PVs requires the autophagy factor Atg5. Atg5 is part of a protein complex that facilitates the transfer of the ubiquitin-like protein Atg8 from the E2-like conjugation enzyme Atg3 to the lipid phosphatidylethanolamine. Here, we show that Atg3 expression, similar to Atg5 expression, is required for IRG and Gbp proteins to dock to PVs. We further demonstrate that expression of a dominant-active, GTP-locked IRG protein variant rescues the PV targeting defect of Atg3- and Atg5-deficient cells, suggesting a possible role for Atg proteins in the activation of IRG proteins. Lastly, we show that IFN-induced cell-autonomous resistance to C. trachomatis infections in mouse cells depends not only on Atg5 and IRG proteins, as previously demonstrated, but also requires the expression of Atg3 and Gbp proteins. These findings provide a foundation for a better understanding of IRG- and Gbp-dependent cell-autonomous resistance and its regulation by Atg proteins.

  5. Whole genome analysis of diverse Chlamydia trachomatis strains identifies phylogenetic relationships masked by current clinical typing

    Science.gov (United States)

    Harris, Simon R.; Clarke, Ian N.; Seth-Smith, Helena M. B.; Solomon, Anthony W.; Cutcliffe, Lesley T.; Marsh, Peter; Skilton, Rachel J.; Holland, Martin J.; Mabey, David; Peeling, Rosanna W.; Lewis, David A.; Spratt, Brian G.; Unemo, Magnus; Persson, Kenneth; Bjartling, Carina; Brunham, Robert; de Vries, Henry J.C.; Morré, Servaas A.; Speksnijder, Arjen; Bébéar, Cécile M.; Clerc, Maïté; de Barbeyrac, Bertille; Parkhill, Julian; Thomson, Nicholas R.

    2012-01-01

    Chlamydia trachomatis is responsible for both trachoma and sexually transmitted infections causing substantial morbidity and economic cost globally. Despite this, our knowledge of its population and evolutionary genetics is limited. Here we present a detailed whole genome phylogeny from representative strains of both trachoma and lymphogranuloma venereum (LGV) biovars from temporally and geographically diverse sources. Our analysis demonstrates that predicting phylogenetic structure using the ompA gene, traditionally used to classify Chlamydia, is misleading because extensive recombination in this region masks true relationships. We show that in many instances ompA is a chimera that can be exchanged in part or whole, both within and between biovars. We also provide evidence for exchange of, and recombination within, the cryptic plasmid, another important diagnostic target. We have used our phylogenetic framework to show how genetic exchange has manifested itself in ocular, urogenital and LGV C. trachomatis strains, including the epidemic LGV serotype L2b. PMID:22406642

  6. CORRELATIONS BETWEEN CONTEMPORARY METHODS IN THE DIAGNOSIS OF CHLAMYDIA TRACHOMATIS UROGENITAL INFECTIONS.

    Directory of Open Access Journals (Sweden)

    Ilko Bakardzhiev

    2011-10-01

    Full Text Available The subject of this study were 486 outpatients between the ages of 17 and 62, diagnosed with urethritis, epidydimitis, prostatitis, cervicitis, endocervicitis, pelvic inflammatory disease and sterility. The following tests were used to make the diagnosis of Chlamydia trachomatis: Enzyme Immunoassay (EIA, Enzyme-Linked Fluorescent Assay (ELFA, Polymerase Chain Reaction DNA amplification for Chlamydia Trachomatis, Neisseria Gonorrhoeae, Mycoplasma Genitalium and Ureaplasma Urealyiticum. Comparison PCR and EIA showed statistically significant difference between the positive results obtained by the two methods (p0,1. EIA is a method that gives a higher percentage of nonspecific positive reactions, while the results obtained from ELFA are much closer to the ones obtained by PCR. According to contemporary evidence based medicine, the developmet of unified standard methods for diagnosis and evaluation is of vital importance, not only for the patient and the treating physician but also concerns for the healthcare system, the general public and the pharmaceutical companies as well.

  7. Detection of Chlamydia pneumoniae in a collection of captive snakes and response to treatment with marbofloxacin.

    Science.gov (United States)

    Rüegg, S R; Regenscheit, N; Origgi, F C; Kaiser, C; Borel, N

    2015-09-01

    In a collection of 58 snakes comprising predominantly Eurasian vipers in Switzerland, five snakes died unexpectedly during hibernation from 2009 to 2012. In one snake, organisms resembling chlamydiae were detected by immunohistochemistry in multiple histiocytic granulomas. Real-time quantitative PCR and microarray analysis were used to determine the presence of Chlamydia pneumoniae in tissue samples and cloacal/choanal swabs from snakes in the collection; 8/53 (15.1%) of the remaining snakes were positive. Although one infected snake had suppurative periglossitis, infection with C. pneumoniae did not appear to be associated with specific clinical signs in snakes. Of seven snakes treated with 5 mg/kg marbofloxacin IM once daily, five became PCR negative for C. pneumoniae following treatment, whereas one animal remained positive and one snake was lost to follow-up.

  8. Exploring Short-Term Responses to Changes in the Control Strategy for Chlamydia trachomatis

    Directory of Open Access Journals (Sweden)

    James Clarke

    2012-01-01

    Full Text Available Chlamydia has a significant impact on public health provision in the developed world. Using pair approximation equations we investigate the efficacy of control programmes for chlamydia on short time scales that are relevant to policy makers. We use output from the model to estimate critical measures, namely, prevalence, incidence, and positivity in those screened and their partners. We combine these measures with a costing tool to estimate the economic impact of different public health strategies. Increasing screening coverage significantly increases the annual programme costs whereas an increase in tracing efficiency initially increases annual costs but over time reduces costs below baseline, with tracing accounting for around 10% of intervention costs. We found that partner positivity is insensitive to changes in prevalence due to screening, remaining at around 33%. Whether increases occur in screening or tracing levels, the cost per treated infection increases from the baseline because of reduced prevalence.

  9. Exploring short-term responses to changes in the control strategy for Chlamydia trachomatis.

    Science.gov (United States)

    Clarke, James; White, K A Jane; Turner, Katy

    2012-01-01

    Chlamydia has a significant impact on public health provision in the developed world. Using pair approximation equations we investigate the efficacy of control programmes for chlamydia on short time scales that are relevant to policy makers. We use output from the model to estimate critical measures, namely, prevalence, incidence, and positivity in those screened and their partners. We combine these measures with a costing tool to estimate the economic impact of different public health strategies. Increasing screening coverage significantly increases the annual programme costs whereas an increase in tracing efficiency initially increases annual costs but over time reduces costs below baseline, with tracing accounting for around 10% of intervention costs. We found that partner positivity is insensitive to changes in prevalence due to screening, remaining at around 33%. Whether increases occur in screening or tracing levels, the cost per treated infection increases from the baseline because of reduced prevalence.

  10. Interaction between the Chlamydia trachomatis histone H1-like protein (Hc1) and DNA

    DEFF Research Database (Denmark)

    Christiansen, Gunna; Pedersen, LB; Koehler, JF;

    1993-01-01

    The gene encoding the Chlamydia trachomatis histone H1-like protein (Hc1) from serovar L2 was cloned into Escherichia coli by use of expression vector pET11d. In this vector, transcription of the gene is under the control of a bacteriophage T7 promoter, and T7 RNA polymerase is inducible in the h......The gene encoding the Chlamydia trachomatis histone H1-like protein (Hc1) from serovar L2 was cloned into Escherichia coli by use of expression vector pET11d. In this vector, transcription of the gene is under the control of a bacteriophage T7 promoter, and T7 RNA polymerase is inducible...

  11. [Oral contraceptive use and prevalence of infection with Chlamydia trachomatis in women (author's transl)].

    Science.gov (United States)

    Kinghorn, G R; Waugh, M A

    1983-05-01

    1080 nonpregnant women ages 16-34 years, presenting for the 1st time at a clinic for sexually transmitted diseases (STD), were examined and screened for infection with Chlamydia trachomatis, Neisseria gonorrheae, Trichomonas vaginalis, and Candida species. The respective prevalence rates were 21.1%, 20.7%, 13.4%, and 27.8%. Isolation rates for Chlamydia trachomatis, either occurring alone or in association with other genital infections, were significantly greater in women using oral contraceptives (OCs). This was not because OC users were more promiscuous. The findings strengthen the case for providing a routine chlamydial culture service for women attending STD clinics. They also indicate that the likelihood of chlamydial infection in women taking OCs is greater. (author's)

  12. An Epidemiologic Analysis of Chlamydia trachomatis and Neisseria gonorrhoeae Infections in Female Federal Prisoners

    Science.gov (United States)

    2002-01-01

    suspected outbreak of vaginal trichomoniasis among female inmates. Sex Trans Dis 1999; 335-338. 11. Fleming D, Wasserheit J. From epidemiological synergy...Morgan SC, Pinson GB. Validity of self-obtained vaginal specimen for the diagnosis of trichomoniasis . J Clin Microbiol 1997; 35:1618-1619. 6...Weisenfeld, HC, Lowry DLB, Phillips H. Self-collection of vaginal swabs for the detection of chlamydia, gonorrhea and trichomoniasis : opportunity to

  13. Plaque Formation by and Plaque Cloning of Chlamydia trachomatis Biovar Trachoma

    OpenAIRE

    Matsumoto, Akira; Izutsu, Hiroshi; Miyashita, Naoyuki; Ohuchi, Masanobu

    1998-01-01

    A new technique for the induction of plaque formation by Chlamydia trachomatis biovar trachoma applicable to the titration of infectivity and cloning of biovar trachoma was established. Three novel strains were cloned and confirmed to be free of glycogen inclusions. The lack of glycogen accumulation correlated with the absence of a 7.5-kb plasmid, which is highly conserved in other strains of C. trachomatis. Although the growth efficiency of these plasmid-free strains was slightly lower than ...

  14. An econometric analysis of screening and treatment of patients with suspected Chlamydia.

    Science.gov (United States)

    Tavakoli, Manouche; Craig, Ann-Marie; Malek, Mo

    2002-02-01

    Chlamydia trachomatis is probably the most common sexually transmitted disease in the Western industrialised countries with devastating consequences. However, it is an infection that can be so easily treated. There are over 50 million new cases occurring each year. In the United States chlamydia is seen as the most common and costly of the bacterial sexually transmitted diseases (STD), with approximately 4 million new cases occurring each year at an estimated total cost of $2.4 billion. The characteristic of this infection is its difficulty of detection that promotes its spread and making its prediction rather complex. Chlamydial infections are commonly asymptomatic or cause mild or non-specific symptoms and signs, which are not easily detected. Approximately 70% of women with endocervical infections and up to 50% of men with urethral infections are asymptomatic and thus not likely to seek medical care. Chlamydia has become known as the "silent epidemic". It is the more frequently identifiable single cause of pelvic inflammatory disease (PID), occurring in an estimated 15-40% of women. The primary objective of the study was to identify factors and quantify their contribution to the risk of being infected with Chlamydia and to construct an easy to use friendly method for early detection. The importance of developing some means of early detection is vital and previous studies suggest that selective screening might be one solution. A logit model was fitted to three broad variables: behavioural, patients' characteristics, and signs/symptoms noted by patient. The age of the women, the number of sexual partners over the past year, previous history of sexually transmitted disease, the use of barrier contraception and patients' and their partners' signs and symptoms were found to be among the most important variables. Such a model should allow patients who are in a high-risk category, allowing appropriate treatment.

  15. Diagnosis of genital Chlamydia trachomatis infections in asymptomatic males by testing urine by PCR.

    OpenAIRE

    Domeika, M; Bassiri, M; Mårdh, P A

    1994-01-01

    An enzyme-linked immunosorbent assay (EIA) (MikroTrak; Syva) was compared with PCR (Amplicor; Roche) for detection of Chlamydia trachomatis in first-void urine (FVU) from 184 men attending a skin and venereal disease clinic. The prevalence of C. trachomatis in the population studied was 18.5%. Discrepant results between Syva EIA and Roche PCR were retested by using major outer membrane protein primer-based PCR. After retesting, the sensitivity, the specificity, and the positive and negative p...

  16. Influence of temperature, medium, and storage duration on Chlamydia trachomatis DNA detection by PCR.

    Science.gov (United States)

    van Dommelen, Laura; Wolffs, Petra F G; van Tiel, Frank H; Dukers, Nicole; Herngreen, Selma B; Bruggeman, Cathrien A; Hoebe, Christian J P A

    2013-03-01

    We validated the use of stored samples for Chlamydia trachomatis research. C. trachomatis DNA was detected by real-time PCR in clinical (urine and self-taken vaginal swabs) and spiked samples using six different media, five different time points (up to 2 years), and four different temperature conditions. C. trachomatis was detected in all 423 samples, and no clinically relevant degradation impact was detected.

  17. Unveiling New Molecular Factors Useful for Detection of Pelvic Inflammatory Disease due to Chlamydia trachomatis Infection

    OpenAIRE

    Carmen Rodriguez-Cerdeira; Elena Sanchez-Blanco; Alberto Molares-Vila; Alfonso Alba

    2012-01-01

    Background. Untreated Chlamydia trachomatis infections in women can result in disease sequelae such as pelvic inflammatory disease (PID), ultimately culminating in tubal occlusion and infertility. While nucleic acid amplification tests can effectively diagnose uncomplicated lower genital tract infections, they are not suitable for diagnosing upper genital tract pathological sequelae. Objective. The purpose of this paper was to provide a comprehensive review of new molecular factors associated...

  18. Efficacy of interventions to increase the uptake of chlamydia screening in primary care: a systematic review

    Directory of Open Access Journals (Sweden)

    Donovan Basil

    2011-08-01

    Full Text Available Abstract Background As most genital chlamydia infections are asymptomatic, screening is the main way to detect and cases for treatment. We undertook a systematic review of studies assessing the efficacy of interventions for increasing the uptake of chlamydia screening in primary care. Methods We reviewed studies which compared chlamydia screening in the presence and the absence of an intervention. The primary endpoints were screening rate or total tests. Results We identified 16 intervention strategies; 11 were randomised controlled trials and five observational studies, 10 targeted females only, five both males and females, and one males only. Of the 15 interventions among females, six were associated with significant increases in screening rates at the 0.05 level including a multifaceted quality improvement program that involved provision of a urine jar to patients at registration (44% in intervention clinics vs. 16% in the control clinic; linking screening to routine Pap smears (6.9% vs. 4.5%, computer alerts for doctors (12.2% vs. 10.6%; education workshops for clinic staff; internet-based continuing medical education (15.5% vs. 12.4%; and free sexual health consultations (16.8% vs. 13.2%. Of the six interventions targeting males, two found significant increases including the multifaceted quality improvement program in which urine jars were provided to patients at registration (45% vs. 15%; and the offering by doctors of a test to all presenting young male clients, prior to consultation (29 vs. 4%. Conclusions Interventions that promoted the universal offer of a chlamydia test in young people had the greatest impact on increasing screening in primary care.

  19. Current crisis or artifact of surveillance: insights into rebound chlamydia rates from dynamic modelling

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    Vickers David M

    2010-03-01

    Full Text Available Abstract Background After initially falling in the face of intensified control efforts, reported rates of sexually transmitted chlamydia in many developed countries are rising. Recent hypotheses for this phenomenon have broadly focused on improved case finding or an increase in the prevalence. Because of many complex interactions behind the spread of infectious diseases, dynamic models of infection transmission are an effective means to guide learning, and assess quantitative conjectures of epidemiological processes. The objective of this paper is to bring a unique and robust perspective to observed chlamydial patterns through analyzing surveillance data with mathematical models of infection transmission. Methods This study integrated 25-year testing volume data from the Canadian province of Saskatchewan with one susceptible-infected-treated-susceptible and three susceptible-infected-treated-removed compartmental models. Calibration of model parameters to fit observed 25-year case notification data, after being combined with testing records, placed constraints on model behaviour and allowed for an approximation of chlamydia prevalence to be estimated. Model predictions were compared to observed case notification trends, and extensive sensitivity analyses were performed to confirm the robustness of model results. Results Model predictions accurately mirrored historic chlamydial trends including an observed rebound in the mid 1990s. For all models examined, the results repeatedly highlighted that increased testing volumes, rather than changes in the sensitivity and specificity of testing technologies, sexual behaviour, or truncated immunological responses brought about by treatment can, explain the increase in observed chlamydia case notifications. Conclusions Our results highlight the significant impact testing volume can have on observed incidence rates, and that simple explanations for these observed increases appear to have been dismissed in

  20. Oral contraceptive use and prevalence of infection with Chlamydia trachomatis in women.

    OpenAIRE

    Kinghorn, G. R.; Waugh, M A

    1981-01-01

    One thousand eight non-pregnant women aged 16-34 years, presenting for the first time at a clinic for sexually transmitted diseases (STD), were examined and screened for infection with Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, and Candida species. The respective prevalence rates were 21.1%, 20.7%, 13.4%, and 27.8%. Isolation rates for C trachomatis, either occurring alone or in association with other genital infections, were significantly greater in women using oral...

  1. Chlamydia trachomatis in women attending a gynaecological outpatient clinic with lower genital tract infection.

    OpenAIRE

    Svensson, L; Weström, L; Mårdh, P A

    1981-01-01

    In a study of 3794 consecutive women attending a gynaecological outpatient clinic with symptoms of lower genital tract infection (LGTI) 350 (9.2%) harboured Chlamydia trachomatis and 83 (2.2%) Neisseria gonorrhoeae. One hundred and ninety-five patients who were later found to have acute salpingitis and 109 other women in whom the chlamydial cultures were spoiled were excluded from the series. Of the remaining 3490 women, 281 were infected with C trachomatis, 42 with N gonorrhoeae, and 17 with...

  2. Association of Chlamydia trachomatis infection with human papillomavirus (HPV) & cervical intraepithelial neoplasia - A pilot study

    OpenAIRE

    Neerja Bhatla; Kriti Puri; Elizabeth Joseph; Alka Kriplani; Venkateswaran K. Iyer; Sreenivas, V

    2013-01-01

    Background & objectives: Human papillomavirus (HPV) is the necessary cause of cervical cancer and Chlamydia trachomatis (CT) is considered a potential cofactor in the development of cervical intraepithelial neoplasia (CIN). The objective of this pilot study was to determine the association of CT infection with HPV, other risk factors for cervical cancer, and CIN in symptomatic women. Methods: A total of 600 consecutively selected women aged 30-74 yr with persistent vaginal discharge, inter...

  3. MRI as a Novel In Vivo Approach for Assessing Structural Changes of Chlamydia Pathology in a Mouse Model

    Science.gov (United States)

    Wang, Shubing; Meng, Xiangjun; Skinner, Julie M.; Heinrichs, Jon H.; Smith, Jeffrey G.; Boddicker, Melissa A.

    2016-01-01

    Chlamydia trachomatis is among the most prevalent of sexually transmitted diseases. While Chlamydia infection is a reportable event and screening has increased over time, enhanced surveillance has not resulted in a reduction in the rate of infections, and Chlamydia infections frequently recur. The development of a preventative vaccine for Chlamydia may be the only effective approach for reducing infection and the frequency of pathological outcomes. Current vaccine research efforts involve time consuming and/or invasive approaches for assessment of disease state, and MRI presents a clinically translatable method for assessing infection and related pathology both quickly and non-invasively. Longitudinal T2-weighted MRI was performed over 63 days on both control or Chlamydia muridarum challenged mice, either with or without elementary body (EB) immunization, and gross necropsy was performed on day 65. A scoring system was developed to assess the number of regions affected by Chlamydia pathology and was used to document pathology over time and at necropsy. The scoring system documented increasing incidence of pathology in the unimmunized and challenged mice (significantly greater compared to the control and EB immunized-challenged groups) by 21 days post-challenge. No differences between the unchallenged and EB immunized-challenged mice were observed. MRI scores at Day 63 were consistently higher than gross necropsy scores at Day 65, although two of the three groups of mice showed no significant differences between the two techniques. In this work we describe the application of MRI in mice for the potential evaluation of disease pathology and sequelae caused by C. muridarum infection and this technique’s potential for evaluation of vaccines for Chlamydia. PMID:27467585

  4. Hospitalisations for pelvic inflammatory disease temporally related to a diagnosis of Chlamydia or gonorrhoea: a retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Joanne Reekie

    Full Text Available OBJECTIVES: The presence and severity of pelvic inflammatory disease (PID symptoms are thought to vary by microbiological etiology but there is limited empirical evidence. We sought to estimate and compare the rates of hospitalisation for PID temporally related to diagnoses of gonorrhoea and chlamydia. METHODS: All women, aged 15-45 years in the Australian state of New South Wales (NSW, with a diagnosis of chlamydia or gonorrhoea between 01/07/2000 and 31/12/2008 were followed by record linkage for up to one year after their chlamydia or gonorrhoea diagnosis for hospitalisations for PID. Standardised incidence ratios compared the incidence of PID hospitalisations to the age-equivalent NSW population. RESULTS: A total of 38,193 women had a chlamydia diagnosis, of which 483 were hospitalised for PID; incidence rate (IR 13.9 per 1000 person-years of follow-up (PYFU (95%CI 12.6-15.1. In contrast, 1015 had a gonorrhoea diagnosis, of which 45 were hospitalised for PID (IR 50.8 per 1000 PYFU, 95%CI 36.0-65.6. The annual incidence of PID hospitalisation temporally related to a chlamydia or gonorrhoea diagnosis was 27.0 (95%CI 24.4-29.8 and 96.6 (95%CI 64.7-138.8 times greater, respectively, than the age-equivalent NSW female population. Younger age, socio-economic disadvantage, having a diagnosis prior to 2005 and having a prior birth were also associated with being hospitalised for PID. CONCLUSIONS: Chlamydia and gonorrhoea are both associated with large increases in the risk of PID hospitalisation. Our data suggest the risk of PID hospitalisation is much higher for gonorrhoea than chlamydia; however, further research is needed to confirm this finding.

  5. Mast cells play an important role in chlamydia pneumoniae lung infection by facilitating immune cell recruitment into the airway.

    Science.gov (United States)

    Chiba, Norika; Shimada, Kenichi; Chen, Shuang; Jones, Heather D; Alsabeh, Randa; Slepenkin, Anatoly V; Peterson, Ellena; Crother, Timothy R; Arditi, Moshe

    2015-04-15

    Mast cells are known as central players in allergy and anaphylaxis, and they play a pivotal role in host defense against certain pathogens. Chlamydia pneumoniae is an important human pathogen, but it is unclear what role mast cells play during C. pneumoniae infection. We infected C57BL/6 (wild-type [WT]) and mast cell-deficient mice (Kit(W-sh/W-sh) [Wsh]) with C. pneumoniae. Wsh mice showed improved survival compared with WT mice, with fewer cells in Wsh bronchoalveolar lavage fluid (BALF), despite similar levels of cytokines and chemokines. We also found a more rapid clearance of bacteria from the lungs of Wsh mice compared with WT mice. Cromolyn, a mast cell stabilizer, reduced BALF cells and bacterial burden similar to the levels seen in Wsh mice; conversely, Compound 48/80, a mast cell degranulator, increased the number of BALF cells and bacterial burden. Histology showed that WT lungs had diffuse inflammation, whereas Wsh mice had patchy accumulations of neutrophils and perivascular accumulations of lymphocytes. Infected Wsh mice had reduced amounts of matrix metalloprotease-9 in BALF and were resistant to epithelial integral membrane protein degradation, suggesting that barrier integrity remains intact in Wsh mice. Mast cell reconstitution in Wsh mice led to enhanced bacterial growth and normal epithelial integral membrane protein degradation, highlighting the specific role of mast cells in this model. These data suggest that mast cells play a detrimental role during C. pneumoniae infection by facilitating immune cell infiltration into the airspace and providing a more favorable replicative environment for C. pneumoniae.

  6. Frequency of Chlamydia Trachomatis in Symptomatic and Asymptomatic Non-pregnant Women in Golestan Province

    Directory of Open Access Journals (Sweden)

    Samira Okhli (MSc

    2016-06-01

    Full Text Available Background and Objective: Chlamydia trachomatis is one of the most common causes of genital infection in men and women. Genital chlamydial infections in women are clinically asymptomatic in 70-80% of the cases; therefore, the lack of timely diagnosis and treatment leads to complications such as infertility and ectopic pregnancy. The aim of this study was to evaluate the frequency of chlamydial infection in symptomatic and asymptomatic women in the Golestan province. Methods: This cross-sectional study was conducted on 150 cervical swab samples obtained from 150 women referred to the clinic, after obtaining written consent and completion of questionnaires. The swab samples were transferred to laboratory in phosphate-buffered saline solution and DNA extraction was carried out using phenol-chloroform and boiling methods. The frequency of chlamydial infection was evaluated by PCR. Results: None of the tested samples were found as Chlamydia-positive. Conclusion: The findings require that some more extensive research with larger sample sizes and dispersed population be performed to determine the true prevalence. Considering the serious complications of chlamydial infections and its asymptomatic nature, a highly sensitive and specific method such as PCR should be used to detect Chlamydia. It is suggested that this method be used along with a complementary test to obtain the results that are more accurate. Furthermore, conducting simultaneous studies on other populations at risk will be very helpful in obtaining representable national data.

  7. The Infection of Chlamydia Pneumonia in Patients with Acute Myocardial Infarction

    Institute of Scientific and Technical Information of China (English)

    李涛; 许香广; 张国良; 方卫华

    2004-01-01

    Objectives To study the association between infection with chlamydia pneumonia and acute myocardial infarction (AMI). Methods Serology of chlamydia pneumoniae specific IgG、IgM antibodies were measured by microimmunofluorescence test in groups of acute myocardial infarction (AMI) and health control(HC). Results The total infection positive rates were 30.6% in HC group and 88.1% in AMI group, including the previous infection rates which were 30.6% and 71.4%, while the acute infection rates were 0% and 16.7%. The frequency of total infection, previous infection and acute infection was significantly higher in AMI group than in the HC group. Odds Ratio for the development of AMI were 16.82, 5.68, 14.2, respectively(95% CI 5.83 to 48.54,2.46 to 13.11, 1.68 to 119.97). Geometric mean IgG titre was significantly higher in patients with AMI compared with the HC group (P< 0.01). There is no IgM positive in HC group but there were two cases in AMI group. Conclusions The presence of high titers of immmunoglobulin G in AMI. Chlamydia pneumonia infection may be a risk factor for the AMI .

  8. Targeted disruption of Chlamydia trachomatis invasion by in trans expression of dominant negative Tarp effectors

    Directory of Open Access Journals (Sweden)

    Christopher J Parrett

    2016-08-01

    Full Text Available Chlamydia trachomatis invasion of eukaryotic host cells is facilitated, in part, by the type III secreted effector protein, Tarp. The role of Tarp in chlamydiae entry of host cells is supported by molecular approaches that examined recombinant Tarp or Tarp effectors expressed within heterologous systems. A major limitation in the ability to study the contribution of Tarp to chlamydial invasion of host cells was the prior absence of genetic tools for chlamydiae. Based on our knowledge of Tarp domain structure and function along with the introduction of genetic approaches in C. trachomatis, we hypothesized that Tarp function could be disrupted in vivo by the introduction of dominant negative mutant alleles. We provide evidence that transformed C. trachomatis produced epitope tagged Tarp, which was secreted into the host cell during invasion. We examined the effects of domain specific Tarp mutations on chlamydial invasion and growth and demonstrate that C. trachomatis clones harboring engineered Tarp mutants lacking either the actin binding domain or the phosphorylation domain had reduced levels of invasion into host cells. These data provide the first in vivo evidence for the critical role of Tarp in C. trachomatis pathogenesis and indicate that chlamydial invasion of host cells can be attenuated via the introduction of engineered dominant negative type three effectors.

  9. Evolutionary Cell Biology of Division Mode in the Bacterial Planctomycetes-Verrucomicrobia- Chlamydiae Superphylum

    Science.gov (United States)

    Rivas-Marín, Elena; Canosa, Inés; Devos, Damien P.

    2016-01-01

    Bacteria from the Planctomycetes, Verrucomicrobia, and Chlamydiae (PVC) superphylum are exceptions to the otherwise dominant mode of division by binary fission, which is based on the interaction between the FtsZ protein and the peptidoglycan (PG) biosynthesis machinery. Some PVC bacteria are deprived of the FtsZ protein and were also thought to lack PG. How these bacteria divide is still one of the major mysteries of microbiology. The presence of PG has recently been revealed in Planctomycetes and Chlamydiae, and proteins related to PG synthesis have been shown to be implicated in the division process in Chlamydiae, providing important insights into PVC mechanisms of division. Here, we review the historical lack of observation of PG in PVC bacteria, its recent detection in two phyla and its involvement in chlamydial cell division. Based on the detection of PG-related proteins in PVC proteomes, we consider the possible evolution of the diverse division mechanisms in these bacteria. We conclude by summarizing what is known and what remains to be understood about the evolutionary cell biology of PVC division modes. PMID:28018303

  10. Evolutionary cell biology of division mode in the bacterial Planctomycetes-Verrucomicrobia-Chlamydiae superphylum

    Directory of Open Access Journals (Sweden)

    Elena Rivas-Marín

    2016-12-01

    Full Text Available Bacteria from the Planctomycetes, Verrucomicrobia and Chlamydiae (PVC superphylum are exceptions to the otherwise dominant mode of division by binary fission, which is based on the interaction between the FtsZ protein and the peptidoglycan (PG biosynthesis machinery. Some PVC bacteria are deprived of the FtsZ protein and were also thought to lack PG. How these bacteria divide is still one of the major mysteries of microbiology. The presence of PG has recently been revealed in Planctomycetes and Chlamydiae, and proteins related to PG synthesis have been shown to be implicated in the division process in Chlamydiae, providing important insights into PVC mechanisms of division. Here, we review the historical lack of observation of PG in PVC bacteria, its recent detection in two phyla and its involvement in chlamydial cell division. Based on the detection of PG-related proteins in PVC proteomes, we consider the possible evolution of the diverse division mechanisms in these bacteria. We conclude by summarizing what is known and what remains to be understood about the evolutionary cell biology of PVC division modes.

  11. The incidence of pelvic inflammatory disease in untreated women infected with Chlamydia trachomatis: a structured review.

    Science.gov (United States)

    Risser, W L; Risser, J M H

    2007-11-01

    Because of the long-term consequences of pelvic inflammatory disease (PID), the cost-effectiveness of Chlamydia trachomatis screening depends in part on the incidence of PID in untreated, chlamydia-infected women. The aim of this study was to evaluate the original research assessing the incidence of PID following C. trachomatis infection. We conducted a thorough search of the literature and selected all available prospective cohort studies. Six studies had original data: the incidence of PID varied from 0% (97.5% confidence interval [CI] 0-12%) during one year of follow-up of 30 women to 30% (95% CI 12-54%) during 50 days of follow-up of 20 women. Studies that included asymptomatic women in other settings reported a lower incidence than those that evaluated women in sexually transmitted disease clinics. In conclusion, no study was of a size or quality to answer our research question definitively. Investigators and clinicians planning chlamydia-screening programmes need to be cognizant of the inconclusive incidence data.

  12. Chlamydia trachomatis infections in eastern Europe: legal aspects, epidemiology, diagnosis, and treatment

    Science.gov (United States)

    Domeika, M; Hallen, A; Karabanov, L; Chudomirova, K; Gruber, F; Unzeitig, V; Poder, A; Deak, J; Jakobsone, I; Lapinskaite, G; Dajek, Z; Akovbian, V; Gomberg, M; Khryanin, A; Savitcheva, A; Takac, I; Glazkova, L; Vinograd, N; Nedeljkovic, M

    2002-01-01

    Objectives: Knowledge concerning genital Chlamydia trachomatis infections in eastern Europe is scarce. Data on the legal aspects, epidemiology, diagnosis, and treatment of the infection have never been collected, summarised, and presented to the international scientific community. The aim of this study was to present the current situation on the main aspects of chlamydial infections in the countries of eastern Europe. Methods: Written questionnaires concerning legal aspects, epidemiology, diagnosis, and treatment of the infection were distributed among national STI operating administrators as well as researchers who had presented papers at earlier meetings of European chlamydia or STI societies. Results: Most of the countries have not legalised reporting of chlamydial infections and in those who have done so, the quality of the reporting system is poor. Contact tracing is mostly done on a voluntary basis. Reported chlamydia incidence varies from 21 to 276 per 100 000 inhabitants. The most commonly used diagnostic test remains the direct immunofluorescence test; however, some tendencies towards nucleic acid amplification are in evidence. Diagnostic services are paid for by the patient himself, while treatment in many countries is partially or completely covered by public insurance. Conclusions: This is the first report summarising data concerning the situation on C trachomatis infections in eastern Europe. The reporting system and diagnosis of C trachomatis infections remain suboptimal, which allows neither control of the epidemiological situation nor optimal treatment of the patients. The most urgent work currently necessary is the education of professionals and the general population. PMID:12081171

  13. The immune response against Chlamydia suis genital tract infection partially protects against re-infection.

    Science.gov (United States)

    De Clercq, Evelien; Devriendt, Bert; Yin, Lizi; Chiers, Koen; Cox, Eric; Vanrompay, Daisy

    2014-09-25

    The aim of the present study was to reveal the characteristic features of genital Chlamydia suis infection and re-infection in female pigs by studying the immune response, pathological changes, replication of chlamydial bacteria in the genital tract and excretion of viable bacteria. Pigs were intravaginally infected and re-infected with C. suis strain S45, the type strain of this species. We demonstrated that S45 is pathogenic for the female urogenital tract. Chlamydia replication occurred throughout the urogenital tract, causing inflammation and pathology. Furthermore, genital infection elicited both cellular and humoral immune responses. Compared to the primo-infection of pigs with C. suis, re-infection was characterized by less severe macroscopic lesions and less chlamydial elementary bodies and inclusions in the urogenital tract. This indicates the development of a certain level of protection following the initial infection. Protective immunity against re-infection coincided with higher Chlamydia-specific IgG and IgA antibody titers in sera and vaginal secretions, higher proliferative responses of peripheral blood mononuclear cells (PBMC), higher percentages of blood B lymphocytes, monocytes and CD8⁺ T cells and upregulated production of IFN-γ and IL-10 by PBMC.

  14. Mycoplasma pneumoniae and Chlamydia spp. infection in community-acquired pneumonia, Germany, 2011-2012.

    Science.gov (United States)

    Dumke, Roger; Schnee, Christiane; Pletz, Mathias W; Rupp, Jan; Jacobs, Enno; Sachse, Konrad; Rohde, Gernot

    2015-03-01

    Mycoplasma pneumoniae and Chlamydia spp., which are associated with community-acquired pneumonia (CAP), are difficult to propagate, and can cause clinically indistinguishable disease patterns. During 2011-2012, we used molecular methods to test adult patients in Germany with confirmed CAP for infection with these 2 pathogens. Overall, 12.3% (96/783) of samples were positive for M. pneumoniae and 3.9% (31/794) were positive for Chlamydia spp.; C. psittaci (2.1%) was detected more frequently than C. pneumoniae (1.4%). M. pneumoniae P1 type 1 predominated, and levels of macrolide resistance were low (3.1%). Quarterly rates of M. pneumoniae-positive samples ranged from 1.5% to 27.3%, showing a strong epidemic peak for these infections, but of Chlamydia spp. detection was consistent throughout the year. M. pneumoniae-positive patients were younger and more frequently female, had fewer co-occurring conditions, and experienced milder disease than did patients who tested negative. Clinicians should be aware of the epidemiology of these pathogens in CAP.

  15. Porcine retinal cell line VIDO R1 and Chlamydia suis to modelize ocular chlamydiosis.

    Science.gov (United States)

    Käser, Tobias; Cnudde, Thomas; Hamonic, Glenn; Rieder, Meghanne; Pasternak, J Alex; Lai, Ken; Tikoo, Suresh K; Wilson, Heather L; Meurens, François

    2015-08-15

    Human ocular Chlamydia trachomatis infections can lead to trachoma, the major cause of infectious blindness worldwide. Trachoma control strategies are very helpful but logistically challenging, and a trachoma vaccine is needed but not available. Pigs are a valuable large animal model for various immunological questions and could facilitate the study of human ocular chlamydial infections. In addition, a recent study identified the zoonotic potential of Chlamydia suis, the natural pathogen of pigs. In terms of the One Health Initiative, understanding the host-pathogen-interactions and finding a vaccine for porcine chlamydia infections would also benefit human health. Thus, we infected the porcine retinal cell line VIDO R1 with C. suis and analyzed the chlamydial life cycle and the innate immune response of the infected cells. Our results indicate that C. suis completes its life cycle in VIDO R1 cells within 48 h, comparable to C. trachomatis in humans. C. suis infection of VIDO R1 cells led to increased levels of various innate immune mediators like pathogen recognition receptors, cytokines and chemokines including IL6, TNFα, and MMP9, also most relevant in human C. trachomatis infections. These results illustrate the first steps in the host-pathogen-interactions of ocular C. suis infections in pigs and show their similarity to C. trachomatis infections in humans, justifying further testing of pigs as an animal model for human trachoma.

  16. Characterization of native and recombinant 75-kilodalton immunogens from Chlamydia trachomatis serovar L2

    DEFF Research Database (Denmark)

    Birkelund, Svend; Lundemose, AG; Christiansen, Gunna

    1989-01-01

    A 75-kilodalton (kDa) immunogen from Chlamydia trachomatis serovar L2 was characterized. The 75-kDa protein was localized in the cytoplasm of chlamydiae and was shown to be a protein synthesized early in the developmental cycle of chlamydiae. A gene library was made by the recombinant DNA technique......, using the expression vectors pEX1, pEX2, and pEX3. From this library one clone was found which reacted with a monoclonal antibody against the 75-kDa immunogen of C. trachomatis. The 75-kDa protein produced by the recombinant Escherichia coli was expressed independently of the promoter for the hybrid...... protein cro-betagalactosidase. Thus it is not produced as a fusion protein. Epitope mapping of the 75-kDa protein from C. trachomatis L2 and from the recombinant E. coli performed by Staphylococcus aureus V8 protease digestion showed that the two proteins are identical. Furthermore, patient sera reacted...

  17. Co-cultivation of conjunctival epithelial cells and Chlamydia trachomatis: electron microscopic findings.

    Science.gov (United States)

    Kim, D S; Ko, M K; Kang, K T

    1998-06-01

    This study used primary culture of rabbit conjunctival epithelial cells to investigate the infection process of chlamydia. The epithelial cells isolated from conjunctiva of rabbit were initially cultured for three weeks. After attaining confluence they were infected with Chlamydia trachomatis (C. trachomatis) serotype D, and after co-cultivation for 24, 48, and 96 hours, electron microscopic study was performed. An inclusion body, a characteristic finding of chlamydial infection, was observed in the vicinity of the nucleus after 24 hours of co-cultivation. It contained a large number of elementary and reticulate bodies and their intermediate forms. Infectious particles known as elementary bodies were noted in the inclusion as 20 to 30 microns sized round bodies with an electron dense core. Reticulate bodies were also noted; they too were round but somewhat pleomorphic and larger than elementary bodies. Some reticulate bodies multiplied actively by means of binary fission. In this study, we observed the characteristic changes of C. trachomatis-infected cells; this in-vitro system might provide a suitable model for the study of some aspects of the pathogenesis of ocular chlamydia infection.

  18. Survival of environmental mycobacteria in Acanthamoeba polyphaga.

    Science.gov (United States)

    Adékambi, Toïdi; Ben Salah, Skandar; Khlif, Mohamed; Raoult, Didier; Drancourt, Michel

    2006-09-01

    Free-living amoebae in water are hosts to many bacterial species living in such an environment. Such an association enables bacteria to select virulence factors and survive in adverse conditions. Waterborne mycobacteria (WBM) are important sources of community- and hospital-acquired outbreaks of nontuberculosis mycobacterial infections. However, the interactions between WBM and free-living amoebae in water have been demonstrated for only few Mycobacterium spp. We investigated the ability of a number (n = 26) of Mycobacterium spp. to survive in the trophozoites and cysts of Acanthamoeba polyphaga. All the species tested entered the trophozoites of A. polyphaga and survived at this location over a period of 5 days. Moreover, all Mycobacterium spp. survived inside cysts for a period of 15 days. Intracellular Mycobacterium spp. within amoeba cysts survived when exposed to free chlorine (15 mg/liter) for 24 h. These data document the interactions between free-living amoebae and the majority of waterborne Mycobacterium spp. Further studies are required to examine the effects of various germicidal agents on the survival of WBM in an aquatic environment.

  19. The survival of Coxiella burnetii in soils

    Science.gov (United States)

    Evstigneeva, A. S.; Ul'Yanova, T. Yu.; Tarasevich, I. V.

    2007-05-01

    Coxiella burnetii is a pathogen of Q-fever—a widespread zoonosis. The effective adaptation of C. burnetii to intracellular existence is in contrast with its ability to survive in the environment outside the host cells and its resistance to chemical and physical agents. Its mechanism of survival remains unknown. However, its survival appears to be related to the developmental cycle of the microorganism itself, i.e., to the formation of its dormant forms. The survival of Coxiella burnetii was studied for the first time. The pathogenic microorganism was inoculated into different types of soil and cultivated under different temperatures. The survival of the pathogen was verified using a model with laboratory animals (mice). Viable C. burnetii were found in the soil even 20 days after their inoculation. The relationship between the organic carbon content in the soils and the survival of C. burnetii was revealed. Thus, the results obtained were the first to demonstrate that the soil may serve as a reservoir for the preservation and further spreading of the Q-fever pathogen in the environment, on the one hand, and reduce the risk of epidemics, on the other.

  20. Collective Resistance in Microbial Communities by Intracellular Antibiotic Deactivation

    Science.gov (United States)

    Sorg, Robin A.; Lin, Leo; van Doorn, G. Sander; Sorg, Moritz; Olson, Joshua; Nizet, Victor; Veening, Jan-Willem

    2016-01-01

    The structure and composition of bacterial communities can compromise antibiotic efficacy. For example, the secretion of β-lactamase by individual bacteria provides passive resistance for all residents within a polymicrobial environment. Here, we uncover that collective resistance can also develop via intracellular antibiotic deactivation. Real-time luminescence measurements and single-cell analysis demonstrate that the opportunistic human pathogen Streptococcus pneumoniae grows in medium supplemented with chloramphenicol (Cm) when resistant bacteria expressing Cm acetyltransferase (CAT) are present. We show that CAT processes Cm intracellularly but not extracellularly. In a mouse pneumonia model, more susceptible pneumococci survive Cm treatment when coinfected with a CAT-expressing strain. Mathematical modeling predicts that stable coexistence is only possible when antibiotic resistance comes at a fitness cost. Strikingly, CAT-expressing pneumococci in mouse lungs were outcompeted by susceptible cells even during Cm treatment. Our results highlight the importance of the microbial context during infectious disease as a potential complicating factor to antibiotic therapy. PMID:28027306

  1. Macrophage activation induced by Brucella DNA suppresses bacterial intracellular replication via enhancing NO production.

    Science.gov (United States)

    Liu, Ning; Wang, Lin; Sun, Changjiang; Yang, Li; Tang, Bin; Sun, Wanchun; Peng, Qisheng

    2015-12-01

    Brucella DNA can be sensed by TLR9 on endosomal membrane and by cytosolic AIM2-inflammasome to induce proinflammatory cytokine production that contributes to partially activate innate immunity. Additionally, Brucella DNA has been identified to be able to act as a major bacterial component to induce type I IFN. However, the role of Brucella DNA in Brucella intracellular growth remains unknown. Here, we showed that stimulation with Brucella DNA promote macrophage activation in TLR9-dependent manner. Activated macrophages can suppresses wild type Brucella intracellular replication at early stage of infection via enhancing NO production. We also reported that activated macrophage promotes bactericidal function of macrophages infected with VirB-deficient Brucella at the early or late stage of infection. This study uncovers a novel function of Brucella DNA, which can help us further elucidate the mechanism of Brucella intracellular survival.

  2. Complementary roles of intracellular and pericellular collagen degradation pathways in vivo

    DEFF Research Database (Denmark)

    Wagenaar-Miller, Rebecca A; Engelholm, Lars H; Gavard, Julie

    2007-01-01

    these two pathways is unclear and even controversial. Here we show that intracellular and pericellular collagen turnover pathways have complementary roles in vivo. Individual deficits in intracellular collagen degradation (urokinase plasminogen activator receptor-associated protein/Endo180 ablation......Collagen degradation is essential for cell migration, proliferation, and differentiation. Two key turnover pathways have been described for collagen: intracellular cathepsin-mediated degradation and pericellular collagenase-mediated degradation. However, the functional relationship between......) or pericellular collagen degradation (membrane type 1-matrix metalloproteinase ablation) were compatible with development and survival. Their combined deficits, however, synergized to cause postnatal death by severely impairing bone formation. Interestingly, this was mechanistically linked to the proliferative...

  3. Identifying Relationships between High-Risk Sexual Behaviors and Screening Positive for Chlamydia and Gonorrhea in School-Wide Screening Events

    Science.gov (United States)

    Salerno, Jennifer; Darling-Fisher, Cindy; Hawkins, Nicole M.; Fraker, Elizabeth

    2013-01-01

    Background: This article describes a school-wide sexually transmitted infection (STI) screening to identify adolescent high-risk sexual behaviors, STI history/incidence, and presence of chlamydia and gonorrhea, and examines relationships between high-risk behaviors and screening positive for chlamydia and gonorrhea in an alternative high school…

  4. Identification of two novel genes encoding 97- to 99-kilodalton outer membrane proteins of Chlamydia pneumoniae.Infect Immun. 1999 Jan;67(1):375-83

    DEFF Research Database (Denmark)

    Knudsen, K; Madsen, AS; Mygind, P

    1999-01-01

    of putative outer membrane proteins encoded by the Chlamydia psittaci and Chlamydia trachomatis gene families. By use of a monospecific polyclonal antibody against purified recombinant Omp4, it was shown that without heating, the protein migrated at 65 to 75 kDa in sodium dodecyl sulfate-polyacrylamide gel...

  5. Better than nothing? Patient-delivered partner therapy and partner notification for chlamydia: the views of Australian general practitioners

    Directory of Open Access Journals (Sweden)

    Bowden Francis J

    2010-09-01

    Full Text Available Abstract Background Genital chlamydia is the most commonly notified sexually transmissible infection (STI in Australia and worldwide and can have serious reproductive health outcomes. Partner notification, testing and treatment are important facets of chlamydia control. Traditional methods of partner notification are not reaching enough partners to effectively control transmission of chlamydia. Patient-delivered partner therapy (PDPT has been shown to improve the treatment of sexual partners. In Australia, General Practitioners (GPs are responsible for the bulk of chlamydia testing, diagnosis, treatment and follow up. This study aimed to determine the views and practices of Australian general practitioners (GPs in relation to partner notification and PDPT for chlamydia and explored GPs' perceptions of their patients' barriers to notifying partners of a chlamydia diagnosis. Methods In-depth, semi-structured telephone interviews were conducted with 40 general practitioners (GPs from rural, regional and urban Australia from November 2006 to March 2007. Topics covered: GPs' current practice and views about partner notification, perceived barriers and useful supports, previous use of and views regarding PDPT. Transcripts were imported into NVivo7 and subjected to thematic analysis. Data saturation was reached after 32 interviews had been completed. Results Perceived barriers to patients telling partners (patient referral included: stigma; age and cultural background; casual or long-term relationship, ongoing relationship or not. Barriers to GPs undertaking partner notification (provider referral included: lack of time and staff; lack of contact details; uncertainty about the legality of contacting partners and whether this constitutes breach of patient confidentiality; and feeling both personally uncomfortable and inadequately trained to contact someone who is not their patient. GPs were divided on the use of PDPT - many felt concerned that it is not

  6. "...they should be offering it": a qualitative study to investigate young peoples' attitudes towards chlamydia screening in GP surgeries

    Directory of Open Access Journals (Sweden)

    Wallace Louise M

    2010-10-01

    Full Text Available Abstract Background Despite the known health and healthcare costs of untreated chlamydia infection and the efforts of the National Chlamydia Screening Programme (NCSP to control chlamydia through early detection and treatment of asymptomatic infection, the rates of screening are well below the 2010-2011 target rate of 35%. General Practitioner (GP surgeries are a key venue within the NCSP however; previous studies indicate that GP surgery staff are concerned that they may offend their patients by offering a screen. This study aimed to identify the attitudes to, and preferences for, chlamydia screening in 15-24 year old men and women attending GP surgeries (the target group. Methods We undertook 36 interviews in six surgeries of differing screening rates. Our participants were 15-24 year olds attending a consultation with a staff member. Data were analysed thematically. Results GP surgeries are acceptable to young people as a venue for opportunistic chlamydia screening and furthermore they think it is the duty of GP surgery staff to offer it. They felt strongly that it is important for surgery staff to have a non-judgemental attitude and they did not want to be singled out as 'needing' a chlamydia screen. Furthermore, our sample reported a strong preference for being offered a screen by staff and providing the sample immediately at the surgery rather than taking home a testing kit. The positive attitude and subjective norms demonstrated by interviewees suggest that young peoples' behaviour would be to accept a screen if it was offered to them. Conclusion Young people attending GP surgeries have a positive attitude towards chlamydia screening and given the right environment are likely to take up the offer in this setting. The right environment involves normalising screening by offering a chlamydia screen to all 15-24 year olds at every interaction with staff, offering screening with a non-judgemental attitude and minimising barriers to screening

  7. The Study of Chlamydia Pneumoniae DNA in the Peripheral Blood Mononuclear Cell of Coronary Heart Disease

    Institute of Scientific and Technical Information of China (English)

    Li Tao; Xu Xiang Guang; Zhang Guo Liang; Fang Weihua

    2004-01-01

    Objectives To detection of chlamydia pneumoniae (Cpn) DNA in the circulating mononuclear cell fractions of coronary heart disease and to investigate the association between infection with chlamydia pneumoniae and coronary heart disease (CHD) and prospectively whether blood -based nested polymerase chain reaction ( nPCR ) is useful in identifying Cpn infection. Methods The peripheral blood mononuclear cell (PBMC) Cpn DNA was examined using nPCR technique and confirmed by electrophoresis in 150 patients with CHD. Select 55 patients with clinical suspected CHD but angiography result are normal as control group (CG). Then we conducted a prospective , randomized, double - blind, placebo -controlled study of 6 months of azithromycin and placebo treatment in CHD group. Patients with Cpn DNA positive were then randomized to receive azithromycin or placebo. After treatment blood sample were collected for repeated measurement . Results Chlamydia pneumoniae DNA was detected in 49(32.7% ) of 150persons with CHD and in 1 ( 1.8% ) of 55 persons with control group,odds ratio 26.2, 95% confidence interva13.52 - 194.98. The positivity rates of nPCR in CHD groups were higher than those in control group. 16 cases (29. 1% ) in latent coronary heart diseases(LCHD) group , 19 cases (39.6%) in unstable angina(UAP) group ,and 14 cases (29.9%) in acute myocardial infarction (AMI)group were Cpn positive by nPCR. There were no significant difference among in AMIUAP and LCHD group. There were significiant difference in Cpn DNA negative rates after the azithromycin and the placebo treatment. Conclusions Chlamydia pneumoniae is present in PBMC of a significant proportion of persons with CHD. The potential role of chlamydia pneumoniae in coronary atherosclerosis may therefore be more related to acceleration of disease or systemic effects by persistent infection than to sudden initiation of progressive coronary artery disease by acute infection. The detection of Cpn DNA in PBMC with nPCR may be

  8. Internal affairs: investigating the Brucella intracellular lifestyle.

    Science.gov (United States)

    von Bargen, Kristine; Gorvel, Jean-Pierre; Salcedo, Suzana P

    2012-05-01

    Bacteria of the genus Brucella are Gram-negative pathogens of several animal species that cause a zoonotic disease in humans known as brucellosis or Malta fever. Within their hosts, brucellae reside within different cell types where they establish a replicative niche and remain protected from the immune response. The aim of this article is to discuss recent advances in the field in the specific context of the Brucella intracellular 'lifestyle'. We initially discuss the different host cell targets and their relevance during infection. As it represents the key to intracellular replication, the focus is then set on the maturation of the Brucella phagosome, with particular emphasis on the Brucella factors that are directly implicated in intracellular trafficking and modulation of host cell signalling pathways. Recent data on the role of the type IV secretion system are discussed, novel effector molecules identified and how some of them impact on trafficking events. Current knowledge on Brucella gene regulation and control of host cell death are summarized, as they directly affect intracellular persistence. Understanding how Brucella molecules interplay with their host cell targets to modulate cellular functions and establish the intracellular niche will help unravel how this pathogen causes disease.

  9. The duration of Chlamydia muridarum genital tract infection and associated chronic pathological changes are reduced in IL-17 knockout mice but protection is not increased further by immunization.

    Science.gov (United States)

    Andrew, Dean W; Cochrane, Melanie; Schripsema, Justin H; Ramsey, Kyle H; Dando, Samantha J; O'Meara, Connor P; Timms, Peter; Beagley, Kenneth W

    2013-01-01

    IL-17 is believed to be important for protection against extracellular pathogens, where clearance is dependent on neutrophil recruitment and local activation of epithelial cell defences. However, the role of IL-17 in protection against intracellular pathogens such as Chlamydia is less clear. We have compared (i) the course of natural genital tract C. muridarum infection, (ii) the development of oviduct pathology and (iii) the development of vaccine-induced immunity against infection in wild type (WT) BALB/c and IL-17 knockout mice (IL-17-/-) to determine if IL-17-mediated immunity is implicated in the development of infection-induced pathology and/or protection. Both the magnitude and duration of genital infection was significantly reduced in IL-17-/- mice compared to BALB/c. Similarly, hydrosalpinx was also greatly reduced in IL-17-/- mice and this correlated with reduced neutrophil and macrophage infiltration of oviduct tissues. Matrix metalloproteinase (MMP) 9 and MMP2 were increased in WT oviducts compared to IL-17-/- animals at day 7 post-infection. In contrast, oviducts from IL-17-/- mice contained higher MMP9 and MMP2 at day 21. Infection also elicited higher levels of Chlamydia-neutralizing antibody in serum of IL-17-/- mice than WT mice. Following intranasal immunization with C. muridarumMajor Outer Membrane Protein (MOMP) and cholera toxin plus CpG adjuvants, significantly higher levels of chlamydial MOMP-specific IgG and IgA were found in serum and vaginal washes of IL-17-/- mice. T cell proliferation and IFNγ production by splenocytes was greater in WT animals following in vitro re-stimulation, however vaccination was only effective at reducing infection in WT, not IL-17-/- mice. Intranasal or transcutaneous immunization protected WT but not IL-17-/- mice against hydrosalpinx development. Our data show that in the absence of IL-17, the severity of C. muridarum genital infection and associated oviduct pathology are significantly attenuated, however

  10. The duration of Chlamydia muridarum genital tract infection and associated chronic pathological changes are reduced in IL-17 knockout mice but protection is not increased further by immunization.

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    Dean W Andrew

    Full Text Available IL-17 is believed to be important for protection against extracellular pathogens, where clearance is dependent on neutrophil recruitment and local activation of epithelial cell defences. However, the role of IL-17 in protection against intracellular pathogens such as Chlamydia is less clear. We have compared (i the course of natural genital tract C. muridarum infection, (ii the development of oviduct pathology and (iii the development of vaccine-induced immunity against infection in wild type (WT BALB/c and IL-17 knockout mice (IL-17-/- to determine if IL-17-mediated immunity is implicated in the development of infection-induced pathology and/or protection. Both the magnitude and duration of genital infection was significantly reduced in IL-17-/- mice compared to BALB/c. Similarly, hydrosalpinx was also greatly reduced in IL-17-/- mice and this correlated with reduced neutrophil and macrophage infiltration of oviduct tissues. Matrix metalloproteinase (MMP 9 and MMP2 were increased in WT oviducts compared to IL-17-/- animals at day 7 post-infection. In contrast, oviducts from IL-17-/- mice contained higher MMP9 and MMP2 at day 21. Infection also elicited higher levels of Chlamydia-neutralizing antibody in serum of IL-17-/- mice than WT mice. Following intranasal immunization with C. muridarumMajor Outer Membrane Protein (MOMP and cholera toxin plus CpG adjuvants, significantly higher levels of chlamydial MOMP-specific IgG and IgA were found in serum and vaginal washes of IL-17-/- mice. T cell proliferation and IFNγ production by splenocytes was greater in WT animals following in vitro re-stimulation, however vaccination was only effective at reducing infection in WT, not IL-17-/- mice. Intranasal or transcutaneous immunization protected WT but not IL-17-/- mice against hydrosalpinx development. Our data show that in the absence of IL-17, the severity of C. muridarum genital infection and associated oviduct pathology are significantly attenuated

  11. Host inflammatory response and development of complications of Chlamydia trachomatis genital infection in CCR5-deficient mice and subfertile women with the CCR5delta32 gene deletion.

    Science.gov (United States)

    Barr, Erika L; Ouburg, Sander; Igietseme, Joseph U; Morré, Servaas A; Okwandu, Edith; Eko, Francis O; Ifere, Godwin; Belay, Tesfaye; He, Qing; Lyn, Deborah; Nwankwo, Gift; Lillard, James W; Black, Carolyn M; Ananaba, Godwin A

    2005-08-01

    T cell immunity protects against diseases caused by the obligate intracellular bacterium Chlamydia trachomatis. Incidentally, host inflammatory response that includes T cells appears to also contribute to the pathogenesis of chlamydial diseases such as trachoma and tubal factor infertility (TFI). Therefore, designing effective prevention strategies requires a delineation of immune processes responsible for pathology and those mediating immunity, and identification of the immunogenetic factors predisposing to complication development. The chemokine receptor CCR5 is crucial for T cell activation and function since its deficiency causes suppression of T cell response. We investigated the hypothesis that the clearance of genital chlamydial infection in CCR5-deficient mice could be delayed in the short term; however, a beneficial effect could include protection against inflammation-related complications such as TFI. In a translational study in humans, we investigated the effect of a functional 32 bp deletion in the CCR5 gene on the risk of developing tubal pathology in Dutch Caucasian women with immunologic evidence [i.e., immunoglobulin G (IgG) responses] of chlamydial infection. When genitally-infected wild-type (WT) and CCR5 knockout (CCR5KO) mice were evaluated for microbiologic shedding of chlamydiae, there was a greater intensity of infection and delayed resolution in the knockout mice. However, compared to WT mice, the fertility of infected CCR5KO mice (measured by pregnancy rate) was only mildly affected in the short term and unaffected in the long term (70% vs 30% reduction in the short term, and 50 vs 0% in the long term, respectively). Immunobiologic analysis revealed that the diminished capacity of CCR5KO to control acute chlamydial infection correlated with the relatively low chemokine [interferon-inducible protein 10 (IP-10) and regulated upon activation normal cell expressed and secreted (RANTES)] and cytokine (mainly interferon-gamma and tumor necrosis

  12. Translation inhibition of the developmental cycle protein HctA by the small RNA IhtA is conserved across Chlamydia.

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    Jeremiah Tattersall

    Full Text Available The developmental cycle of the obligate intracellular pathogen Chlamydia trachomatis serovar L2 is controlled in part by the small non-coding RNA (sRNA, IhtA. All Chlamydia alternate in a regulated fashion between the infectious elementary body (EB and the replicative reticulate body (RB which asynchronously re-differentiates back to the terminal EB form at the end of the cycle. The histone like protein HctA is central to RB:EB differentiation late in the cycle as it binds to and occludes the genome, thereby repressing transcription and translation. The sRNA IhtA is a critical component of this regulatory loop as it represses translation of hctA until late in infection at which point IhtA transcription decreases, allowing HctA expression to occur and RB to EB differentiation to proceed. It has been reported that IhtA is expressed during infection by the human pathogens C. trachomatis serovars L2, D and L2b and C. pneumoniae. We show in this work that IhtA is also expressed by the animal pathogens C. caviae and C. muridarum. Expression of HctA in E. coli is lethal and co-expression of IhtA relieves this phenotype. To determine if regulation of HctA by IhtA is a conserved mechanism across pathogenic chlamydial species, we cloned hctA and ihtA from C. trachomatis serovar D, C. muridarum, C. caviae and C. pneumoniae and assayed for rescue of growth repression in E. coli co-expression studies. In each case, co-expression of ihtA with the cognate hctA resulted in relief of growth repression. In addition, expression of each chlamydial species IhtA rescued the lethal phenotype of C. trachomatis serovar L2 HctA expression. As biolayer interferometry studies indicate that IhtA interacts directly with hctA message for all species tested, we predict that conserved sequences of IhtA are necessary for function and/or binding.

  13. Translation inhibition of the developmental cycle protein HctA by the small RNA IhtA is conserved across Chlamydia.

    Science.gov (United States)

    Tattersall, Jeremiah; Rao, Geeta Vittal; Runac, Justin; Hackstadt, Ted; Grieshaber, Scott S; Grieshaber, Nicole A

    2012-01-01

    The developmental cycle of the obligate intracellular pathogen Chlamydia trachomatis serovar L2 is controlled in part by the small non-coding RNA (sRNA), IhtA. All Chlamydia alternate in a regulated fashion between the infectious elementary body (EB) and the replicative reticulate body (RB) which asynchronously re-differentiates back to the terminal EB form at the end of the cycle. The histone like protein HctA is central to RB:EB differentiation late in the cycle as it binds to and occludes the genome, thereby repressing transcription and translation. The sRNA IhtA is a critical component of this regulatory loop as it represses translation of hctA until late in infection at which point IhtA transcription decreases, allowing HctA expression to occur and RB to EB differentiation to proceed. It has been reported that IhtA is expressed during infection by the human pathogens C. trachomatis serovars L2, D and L2b and C. pneumoniae. We show in this work that IhtA is also expressed by the animal pathogens C. caviae and C. muridarum. Expression of HctA in E. coli is lethal and co-expression of IhtA relieves this phenotype. To determine if regulation of HctA by IhtA is a conserved mechanism across pathogenic chlamydial species, we cloned hctA and ihtA from C. trachomatis serovar D, C. muridarum, C. caviae and C. pneumoniae and assayed for rescue of growth repression in E. coli co-expression studies. In each case, co-expression of ihtA with the cognate hctA resulted in relief of growth repression. In addition, expression of each chlamydial species IhtA rescued the lethal phenotype of C. trachomatis serovar L2 HctA expression. As biolayer interferometry studies indicate that IhtA interacts directly with hctA message for all species tested, we predict that conserved sequences of IhtA are necessary for function and/or binding.

  14. The Prevalence of Chlamydia trachomatis Infection in Women Attending Health Clinics in Shiraz, Islamic Republic of Iran

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    Negin Hadi

    2010-01-01

    Full Text Available Background: Chlamydia trachomatis (CT is a common cause of sexually transmitted infections (STI anda prevalent microorganism found in the vaginal discharge of sexually active women. The infection usuallyhas no symptoms; although it may cause chronic complications such as pelvic inflammatory disease (PID,ectopic pregnancy, chronic pelvic pain, tubal infertility and cervical cancer. This study was done, for thefirst time, in Shiraz (southern Iran to determine the prevalence of genital C.T in women.Materials and Methods: A total of 402 women who referred for routine pap smears to randomlyselected health centers in Shiraz were tested with the IMAGEN Chlamydia test, a directimmunofluorescence test for the detection of Chlamydia in human urogenital specimens. Theresults of this test were compared to the socio-demographic condition of each participant as well astheir sexually transmitted disease (STD symptoms, both present and past.Results: The prevalence rate of Chlamydia infection was 8% (32/402. No correlation was foundbetween this infection and age, marital age, number of children, education and occupational statusof the participants. On the other hand, the correlation between the presence of infection and apositive history of STD symptoms, both present and past was significant.Conclusion: Chlamydia infection is quite frequent in our society, where knowledge about STDinfections is scant. Considering the sequelae of this infection and the fact that this is a quiet disease,it seems rational to screen sexually active women and inform them more about this issue.

  15. Development and validation of a real-time PCR for Chlamydia suis diagnosis in swine and humans.

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    Kristien De Puysseleyr

    Full Text Available Pigs are the natural host for Chlamydia suis, a pathogen which is phylogenetically highly related to the human pathogen C. trachomatis. Chlamydia suis infections are generally treated with tetracyclines. In 1998, tetracyline resistant C. suis strains emerged on U.S. pig farms and they are currently present in the Belgian, Cypriote, German, Israeli, Italian and Swiss pig industry. Infections with tetracycline resistant C. suis strains are mainly associated with severe reproductive failure leading to marked economical loss. We developed a sensitive and specific TaqMan probe-based C. suis real-time PCR for examining clinical samples of both pigs and humans. The analytical sensitivity of the real-time PCR is 10 rDNA copies/reaction without cross-amplifying DNA of other Chlamydia species. The PCR was successfully validated using conjunctival, pharyngeal and stool samples of slaughterhouse employees, as well as porcine samples from two farms with evidence of reproductive failure and one farm without clinical disease. Chlamydia suis was only detected in diseased pigs and in the eyes of humans. Positive humans had no clinical complaints. PCR results were confirmed by culture in McCoy cells. In addition, Chlamydia suis isolates were also examined by the tet(C PCR, designed for demonstrating the tetracycline resistance gene tet(C. The tet(C gene was only present in porcine C. suis isolates.

  16. Development and validation of a real-time PCR for Chlamydia suis diagnosis in swine and humans.

    Science.gov (United States)

    De Puysseleyr, Kristien; De Puysseleyr, Leentje; Geldhof, Julie; Cox, Eric; Vanrompay, Daisy

    2014-01-01

    Pigs are the natural host for Chlamydia suis, a pathogen which is phylogenetically highly related to the human pathogen C. trachomatis. Chlamydia suis infections are generally treated with tetracyclines. In 1998, tetracyline resistant C. suis strains emerged on U.S. pig farms and they are currently present in the Belgian, Cypriote, German, Israeli, Italian and Swiss pig industry. Infections with tetracycline resistant C. suis strains are mainly associated with severe reproductive failure leading to marked economical loss. We developed a sensitive and specific TaqMan probe-based C. suis real-time PCR for examining clinical samples of both pigs and humans. The analytical sensitivity of the real-time PCR is 10 rDNA copies/reaction without cross-amplifying DNA of other Chlamydia species. The PCR was successfully validated using conjunctival, pharyngeal and stool samples of slaughterhouse employees, as well as porcine samples from two farms with evidence of reproductive failure and one farm without clinical disease. Chlamydia suis was only detected in diseased pigs and in the eyes of humans. Positive humans had no clinical complaints. PCR results were confirmed by culture in McCoy cells. In addition, Chlamydia suis isolates were also examined by the tet(C) PCR, designed for demonstrating the tetracycline resistance gene tet(C). The tet(C) gene was only present in porcine C. suis isolates.

  17. Efficient intracellular delivery and improved biocompatibility of colloidal silver nanoparticles towards intracellular SERS immuno-sensing.

    Science.gov (United States)

    Bhardwaj, Vinay; Srinivasan, Supriya; McGoron, Anthony J

    2015-06-21

    High throughput intracellular delivery strategies, electroporation, passive and TATHA2 facilitated diffusion of colloidal silver nanoparticles (AgNPs) are investigated for cellular toxicity and uptake using state-of-art analytical techniques. The TATHA2 facilitated approach efficiently delivered high payload with no toxicity, pre-requisites for intracellular applications of plasmonic metal nanoparticles (PMNPs) in sensing and therapeutics.

  18. GTPases in intracellular trafficking: an overview.

    Science.gov (United States)

    Segev, Nava

    2011-02-01

    Small GTPases that belong to the ras sub-families of Rab, Arf, and Rho, and the large GTPase dynamin, regulate intracellular trafficking. This issue of Seminars of Cell and Developmental Biology highlights topics regarding mechanisms by which these GTPases regulate the different steps of vesicular transport: vesicle formation, scission, targeting and fusion. In addition, the emerging roles of GTPases in coordination of individual transport steps as well as coordination of intracellular trafficking with other cellular processes are reviewed. Finally, common structures and mechanisms underlying the function of the ras-like GTPases and the importance of their function to human health and disease are discussed.

  19. Effect of environmental stress factors on the uptake and survival of Campylobacter jejuni in Acanthamoeba castellanii

    DEFF Research Database (Denmark)

    Bui, Thanh Xuan; Qvortrup, Klaus; Wolff, Anders

    2012-01-01

    . jejuni and on its uptake by and intracellular survival within Acanthamoeba castellanii. Results: Heat, starvation and osmotic stress reduced the survival of C. jejuni significantly, whereas oxidative stress had no effect. Quantitative RT-PCR experiments showed that the transcription of virulence genes...

  20. Glutathione provides a source of cysteine essential for intracellular multiplication of Francisella tularensis.

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    Khaled Alkhuder

    2009-01-01

    Full Text Available Francisella tularensis is a highly infectious bacterium causing the zoonotic disease tularemia. Its ability to multiply and survive in macrophages is critical for its virulence. By screening a bank of HimarFT transposon mutants of the F. tularensis live vaccine strain (LVS to isolate intracellular growth-deficient mutants, we selected one mutant in a gene encoding a putative gamma-glutamyl transpeptidase (GGT. This gene (FTL_0766 was hence designated ggt. The mutant strain showed impaired intracellular multiplication and was strongly attenuated for virulence in mice. Here we present evidence that the GGT activity of F. tularensis allows utilization of glutathione (GSH, gamma-glutamyl-cysteinyl-glycine and gamma-glutamyl-cysteine dipeptide as cysteine sources to ensure intracellular growth. This is the first demonstration of the essential role of a nutrient acquisition system in the intracellular multiplication of F. tularensis. GSH is the most abundant source of cysteine in the host cytosol. Thus, the capacity this intracellular bacterial pathogen has evolved to utilize the available GSH, as a source of cysteine in the host cytosol, constitutes a paradigm of bacteria-host adaptation.