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A Multi-Component Prime-Boost Vaccination Regimen with a Consensus MOMP Antigen Enhances Chlamydia trachomatis Clearance.

BACKGROUND: A vaccine for Chlamydia trachomatis is of urgent medical need. We explored bioinformatic approaches to generate an immunogen against C. trachomatis that would induce cross-serovar T-cell responses as (i) CD4(+) T cells have been shown in animal models and human studies to be important in chlamydial protection and (ii) antibody responses may be restrictive and serovar specific. METHODS: A consensus antigen based on over 1,500 major outer membrane protein (MOMP) sequences provided high epitope coverage against the most prevalent C. trachomatis strains in silico. Having designed the …

Lack of Significant Effects of Chlamydia trachomatis Infection on Cervical Adenocarcinoma Risk: Nested Case-Control Study.

BACKGROUND: A role of Chlamydia trachomatis in HPV-induced cervical carcinogenesis has been reported for cervical cancer but studies on cervical adenocarcinoma are limited. METHODS: A total of 1,553 cervical smears taken up to 26 years before diagnosis in a large population-based nested case-control study of cervical adenocarcinoma (AC, 132 cases with matched controls), and adenocarcinoma in situ (AIS, 159 cases with matched controls) were tested for C. trachomatis and HPV DNA by a type-specific PCR bead-based multiplex genotyping (TS-MPG) assay. RESULTS: Only 1.7% of samples were positive f…

The Relationship between Active Trachoma and Ocular Chlamydia trachomatis Infection before and after Mass Antibiotic Treatment.

BACKGROUND: Trachoma is a blinding disease, initiated in early childhood by repeated conjunctival infection with the obligate intracellular bacterium Chlamydia trachomatis. The population prevalence of the clinical signs of active trachoma; ''follicular conjunctivitis" (TF) and/or ''intense papillary inflammation" (TI), guide programmatic decisions regarding the initiation and cessation of mass drug administration (MDA). However, the persistence of TF following resolution of infection at both the individual and population level raises concerns over the suitability of this clinical sign as a ma…

Examining Chlamydia trachomatis and Neisseria gonorrhoeae rates between 2010 and 2015: a population-based observational study.

Bacterial sexually transmitted infections including Chlamydia trachomatis and Neisseria gonorrhoeae remain an important public health concern. We aimed to assess the population-based incidence of C. trachomatis and N. gonorrhoeae in an age-standardized cohort over time. A retrospective study of a large Canadian health region was undertaken between 2010 and 2015 using linked census and digital laboratory data. C. trachomatis and N. gonorrhoeae tests were linked to patient data. Sex and age-standardized incidence rates (IR) and ratios (IRR) were calculated for cases and testing rates. The annual…

Contribution of IL-12A and IL-12B polymorphisms to Chlamydia trachomatis-specific cell-mediated immune responses.

Inherited variance in the IL-12B gene is associated with susceptibility to Chlamydia trachomatis-induced tubal factor infertility and disease severity. In this study, our aim was to discover how polymorphisms in IL-12-coding genes influence C. trachomatis-induced immune responses and IL-12 production. The study population consisted of 240 women. IL-12A and IL-12B single nucleotide polymorphisms (SNPs) were determined from isolated DNA using the Sequenom system with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. We studied lymphocyte proliferative (LP)…

Chlamydia trachomatis infection in young adults - association with concurrent partnerships and short gap length between partners.

BACKGROUND: Sexually transmitted infections (STIs) continue to be highly prevalent in young people. New understanding of sexual risk behaviour is essential for future preventive initiatives. Studies based on self-reported STI history indicate that gap length between sexual partnerships is an important determinant in STI transmission, but little is known about the impact of concurrent partnerships and short gap length. This study aimed to examine the significance of concurrent partnerships and short gap length between serially monogamous partnerships in Chlamydia trachomatis-infected individual…

Estimating age-dependent per-encounter chlamydia trachomatis acquisition risk via a Markov-based state-transition model.

BACKGROUND: Chlamydial infection is a common bacterial sexually transmitted infection worldwide, caused by C. trachomatis. The screening for C. trachomatis has been proven to be successful. However, such success is not fully realized through tailoring the recommended screening strategies for different age groups. This is partly due to the knowledge gap in understanding how the infection is correlated with age. In this paper, we estimate age-dependent risks of acquiring C. trachomatis by adolescent women via unprotected heterosexual acts. METHODS: We develop a time-varying Markov state-transit

Quantitative monitoring of the Chlamydia trachomatis developmental cycle using GFP-expressing bacteria, microscopy and flow cytometry.

Chlamydiae are obligate intracellular bacteria. These pathogens develop inside host cells through a biphasic cycle alternating between two morphologically distinct forms, the infectious elementary body and the replicative reticulate body. Recently, C. trachomatis strains stably expressing fluorescent proteins were obtained. The fluorochromes are expressed during the intracellular growth of the microbe, allowing bacterial visualization by fluorescence microscopy. Whether they are also present in the infectious form, the elementary body, to a detectable level has not been studied. Here, we show

Доля лиц в возрасте 14-39 лет, инфицированных гениталиями хламидии, Соединенные Штаты, 2007-2012 годы.

Инфекция бактериями, хламидия трахоматис (часто называемая "хламидией") является наиболее часто регистрируемой в Соединенных Штатах инфекцией, передающейся половым путем. Уретра — наиболее часто встречающаяся инфекция у самцов, а уретра и шейная шейка чаще всего заражаются у женщин. Вспыльчивая инфекция у женщин может привести к воспалительным заболеваниям таза, что может привести к бесплодию и эктической беременности. Генитальные хламидиальные инфекции, как правило, носят асимптомический характер, и для выявления большинства таких инфекций необходимо провести обследование. В настоящее время х

Совпадение в аннотации оригинала
Infection with the bacterium, Chlamydia trachomatis (often termed "chlamydia") is the most frequently reported sexually transmitted infection in the United States. The urethra is the most common site of infection in males, and the urethra and cervix are most commonly infected in females. Ascending infection in females can cause pelvic inflammatory disease, w…

Chlamydia trachomatis polymorphic membrane protein D is a virulence factor involved in early host-cell interactions.

Chlamydia trachomatis is an obligate intracellular mucosotropic pathogen of significant medical importance. It is the etiological agent of blinding trachoma and bacterial sexually transmitted diseases, infections that afflict hundreds of millions of people globally. The C. trachomatis polymorphic membrane protein D (PmpD) is a highly conserved autotransporter and the target of broadly cross-reactive neutralizing antibodies; however, its role in host-pathogen interactions is unknown. Here we employed a targeted reverse genetics approach to generate a pmpD null mutant that was used to define the…

STING-dependent recognition of cyclic di-AMP mediates type I interferon responses during Chlamydia trachomatis infection.

UNLABELLED: STING (stimulator of interferon [IFN] genes) initiates type I IFN responses in mammalian cells through the detection of microbial nucleic acids. The membrane-bound obligate intracellular bacterium Chlamydia trachomatis induces a STING-dependent type I IFN response in infected cells, yet the IFN-inducing ligand remains unknown. In this report, we provide evidence that Chlamydia synthesizes cyclic di-AMP (c-di-AMP), a nucleic acid metabolite not previously identified in Gram-negative bacteria, and that this metabolite is a prominent ligand for STING-mediated activation of IFN respons…

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

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 …

Lack of association between Chlamydia trachomatis infection and cervical cancer--Taq Man realtime PCR assay findings.

BACKGROUND: Cervical cancer is one of the most common cancers in developing countries and the second most common type of cancer in women globally. Several recent studies suggested a co factor role for Chlamydia trachomatis in pathogenesis of cervical cancer. This study aimed to evaluate existence of C. trachomatis DNA in pathologic blocks of patients with cervical cancer. MATERIALS AND METHODS: Seventy-six formaldehyde fixed paraffin embedded tissue specimens from patients with histologically proven history of cervical cancer as well as 150 blocks from healthy peoples were included in the pre…

Unveiling New Molecular Factors Useful for Detection of Pelvic Inflammatory Disease due to Chlamydia trachomatis Infection.

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 with the diagnosis and prognosis of PID. Material and Methods. The literature was searched using the k…

Toll-like receptor 2-dependent activity of native major outer membrane protein proteosomes of Chlamydia trachomatis.

Chlamydia trachomatis is the most common sexually transmitted bacterial pathogen and the etiologic agent of blinding trachoma. Intracellular signaling pathways leading to host cell inflammation and innate immunity to Chlamydia include those mediated by Toll-like receptors (TLRs) and nucleotide binding oligomerization domain 1 (Nod1) protein. In epithelial cells, TLR-dependent signaling contributes to local immune responses via induction of inflammatory mediators. There is evidence that TLR3, TLR4, and, particularly, TLR2 are critical for Chlamydia-mediated host cell activation and pathology. D…

Whole-genome analysis of diverse Chlamydia trachomatis strains identifies phylogenetic relationships masked by current clinical typing.

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 phylogeny based on whole-genome sequencing of representative strains of C. trachomatis from both trachoma and lymphogranuloma venereum (LGV) biovars from temporally and geographically diverse sources. Our analysis shows that predicting phylogenetic structure using ompA, which is traditionally used to classify Chlamydia, is misleading bec…

Rapid determination of lymphogranuloma venereum serovars of Chlamydia trachomatis by quantitative high-resolution melt analysis (HRMA).

A quantitative high-resolution melt analysis assay was developed to differentiate lymphogranuloma venereum-causing serovars of Chlamydia trachomatis (L1 to L3) from other C. trachomatis serovars (D to K). The detection limit of this assay is approximately 10 copies per reaction, comparable to the limits of other quantitative-PCR-based methods.

High-throughput multistrain polymerase chain reaction quantification of Chlamydia trachomatis from clinical and preclinical urogenital specimens.

Chlamydia trachomatis (CT) is the most prevalent sexually transmitted bacterial pathogen worldwide and causes severe reproductive tract infections. Currently, nucleic acid amplification tests (NAATs) are the gold standard for clinical diagnosis, but most NAATs are labor intensive and limited to specific CT serovars. We developed and validated a quantitative polymerase chain reaction (qPCR) assay that reproducibly detected CT serovars D, E, F, Ia, and Chlamydia muridarum over a linear range of 2 log(10) to 10 log(10) genomes with low coefficients of variation from both experimental and human ur…

Penicillin induced persistence in Chlamydia trachomatis: high quality time lapse video analysis of the developmental cycle.

BACKGROUND: Chlamydia trachomatis is a major human pathogen with a unique obligate intracellular developmental cycle that takes place inside a modified cytoplasmic structure known as an inclusion. Following entry into a cell, the infectious elementary body (EB) differentiates into a non-infectious replicative form known as a reticulate body (RB). RBs divide by binary fission and at the end of the cycle they redifferentiate into EBs. Treatment of C.trachomatis with penicillin prevents maturation of RBs which survive and enlarge to become aberrant RBs within the inclusion in a non-infective pers…

Seroprevalence of antibodies against Chlamydia trachomatis inclusion membrane proteins B and C in infected symptomatic women.

BACKGROUND: Proteins in the inclusion membrane of Chlamydia trachomatis (CT) have been anticipated to play pivotal roles in the molecular and cellular interactions between the pathogen and host. However, there is lack of data on host immunity with respect to antibody responses against chlamydial inclusion proteins. METHODOLOGY: We used full-length fusion proteins for CT inclusion membrane proteins B and C (IncB and IncC respectively), two early-infection phase proteins, to study their role in antibody generation during human infection. RESULTS: Three hundred and fifty-five women (aged 22-36 …