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PubMed1982

Therapeutic abortion and Chlamydia trachomatis infection.

Chlamydia trachomatis was isolated from the cervix of 30 of 218 (13.8%) women admitted for legal termination of pregnancy. During the first two weeks after the abortion seven of the 30 (23.3%) patients developed pelvic inflammatory disease. Four of these had serological evidence of recent active chlamydial infection. Thus, routine examination of patients for genital chlamydial infection before termination of pregnancy is recommended.

Abortion, Therapeutic↗
PubMed1994

Chlamydia trachomatis infections.

Chlamydia trachomatis infections are the most common bacterial cause of sexually transmitted disease in the United States. Although precise incidence of infection is not known, it has been calculated that more than 4 million chlamydial infections occur each year. This article discusses the epidemiology of sexually transmitted chlamydial infections, the spectrum of clinical manifestations and their sequelae, the laboratory diagnosis of genital infections, and antibiotic treatment, emphasizing the significance of these issues for control efforts in the United States.

Adolescent↗
PubMed2005

Development of secondary inclusions in cells infected by Chlamydia trachomatis.

The chlamydiae are obligate intracellular bacteria that occupy a non-acidified vacuole (the inclusion) during their entire developmental cycle. These bacteria produce a set of proteins (Inc proteins) that localize to the surface of the inclusion within infected cells. Chlamydia trachomatis IncA is also commonly found in long fibers that extend away from the inclusion. We used standard and confocal immunofluorescence microscopy to demonstrate that these fibers extend to newly developed inclusions, termed secondary inclusions, within infected cells. Secondary inclusions observed at early time points postinfection were devoid of chlamydial reticulate bodies. Later in the developmental cycle, secondary inclusions containing variable numbers of reticulate bodies were common. Reticulate bodies were also observed within the IncA-laden fibers connecting primary and secondary inclusions. Quantitative differences in secondary inclusion formation were found among clinical isolates, and these differences were associated with serovar. Isolates of serovar G consistently produced secondary inclusions at the highest frequency (P < 0.0001). Similar quantitative studies demonstrated that secondary inclusion formation was associated with segregation of inclusions to daughter cells following cytokinesis. We conclude that the production of secondary inclusions via IncA-laden fibers allows chlamydiae to generate an expanded intracellular niche in which they can grow and may provide a means for continuous infection within progeny cells following cell division.

Bacterial Proteins↗
PubMed2000

Generation of reactive oxygen species and formation and membrane lipid peroxides in cells infected with Chlamydia trachomatis.

OBJECTIVES: Chlamydiae are obligate intracellular pathogens that cause many diseases for which the pathogenic mechanisms are largely unknown. Because reactive oxygen species (ROS) have been implicated in pathogenesis of many viral and bacterial infections, the authors assessed the release of ROS in selected host cells (monocytes, Sup-T1 cells, and Hep-2 cells) infected with Chlamydia trachomatis. METHODS: Infected cell cultures demonstrated a dramatic depletion of uric acid from culture media that was not seen in uninfected cultures. Reactive oxygen species generated in infected cultures were associated with the formation of lipid peroxides in host cell membrane. RESULTS: There was a significant increase in lipid peroxide levels in infected cells compared to uninfected controls. Ascorbic acid treatment of infected cell cultures reduced the formation of membrane lipid peroxides. CONCLUSIONS: These results suggest that ROS produced during chlamydial replication cause membrane lipid peroxidation. The role of ROS-induced membrane damage in chlamydial pathogenesis is discussed.

Ascorbic Acid↗
PubMedDate not supplied

Modern diagnostics of Chlamydia trachomatis infections.

Chlamydia trachomatis (C. trachomatis) is the most common agent of sexually transmitted infections. The clinical spectrum of the disease ranges from urethritis to infertility in women and to trachoma. Intracellular localisation of the pathogen creates a challenge for routine diagnostics. In this review possible diagnostic tests have been presented, varying from classic cell culture analysis and serodiagnostics (Enzyme-linked Immunoassays, Indirect Immunofluorescence) to the most sophisticated nucleic acid analyses (hybridisation, Polymerase Chain Reaction, Transcription Mediated Amplification, Ligase Chain Reaction), Advantages and disadvantages of the leading tests are discussed. Possible reasons of false positive as well as false negative results of genetic testing are presented.

Chlamydia Infections↗
PubMed2003

Cytokine profile in serum and synovial fluid of arthritis patients with Chlamydia trachomatis infection.

Chlamydia trachomatis (Ct)-induced arthritis (CtIA) is characterized by persistent Ct infection, which stimulates secretion of cytokines in vitro. We therefore investigated whether CtIA patients have a unique cytokine profile in synovial fluid or serum in vivo. Because underlying Ct infection is overlooked in a high percentage of patients with initially diagnosed undifferentiated oligoarthritis (UOA), we examined whether determination of cytokines might also be of diagnostic relevance for this arthritis form. Matched serum and synovial fluid specimens from 26 patients with CtIA were analyzed and compared to those from 34 patients with UOA in whom Ct infection was excluded and those of nine patients with rheumatoid arthritis (RA). In 15 CtIA patients, Ct DNA from synovial fluid could be amplified by polymerase chain reaction. The following cytokine or cytokine antagonists were measured by enzyme-linked immunosorbent assay: interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-6, IL-1 receptor antagonist, and soluble TNF receptor p75. No statistically significant differences in cytokine levels between patients with CtIA or the other arthritis forms were detected. Also, comparison between CtIA patients with (n = 17) and without Chlamydia DNA (n = 9) in synovial fluid revealed no significant differences for these cytokines. Cytokine levels in serum and synovial fluid were not different between CtIA, UOA without Ct infection, and RA patients. The intracellular presence of Ct was not associated with a specific profile of these cytokines in vivo.

Adult↗
PubMed1996

Recall of original serologic response after challenge with homologous and heterologous Chlamydia trachomatis serovars.

Chlamydia trachomatis serovar-specific major outer membrane protein (MOMP) antigens are important targets of immune neutralization in vitro, and natural immunity to infection is associated with serovar specificity. Reinfection, often by different serovars, plays an essential role in chlamydial disease pathogenesis. By use of a murine model, the anamnestic serologic response was characterized following priming and challenge inoculations using 6 different serovars. The serologic response was evaluated using synthetic peptides representing MOMP variant segments (VS) 1,2,3, and 4 antigenic same serovar resulted in serologic responses to homologous VS1 peptides. After challenge with a different serovar, anti-VS1 serologic responses were often elicited with specificity to both the priming serovar and the challenge serovar. The recall of serologic response to the original serovar was typically dependent upon the antigenic relationship of the 2 serovars.

Amino Acid Sequence↗
PubMed2006

Diagnosis and treatment of Chlamydia trachomatis infection.

Chlamydia trachomatis infection most commonly affects the urogenital tract. In men, the infection usually is symptomatic, with dysuria and a discharge from the penis. Untreated chlamydial infection in men can spread to the epididymis. Most women with chlamydial infection have minimal or no symptoms, but some develop pelvic inflammatory disease. Chlamydial infection in newborns can cause ophthalmia neonatorum. Chlamydial pneumonia can occur at one to three months of age, manifesting as a protracted onset of staccato cough, usually without wheezing or fever. Treatment options for uncomplicated urogenital infections include a single 1-g dose of azithromycin orally, or doxycycline at a dosage of 100 mg orally twice per day for seven days. The recommended treatment during pregnancy is erythromycin base or amoxicillin. The Centers for Disease Control and Prevention and the U.S. Preventive Services Task Force recommend screening for chlamydial infection in women at increased risk of infection and in all women younger than 25 years.

Amoxicillin↗
PubMed1980

Experimental epididymitis and urethritis in grivet monkeys provoked by Chlamydia trachomatis.

Recently Chlamydia trachomatis has been indicated as a common cause of acute epididymitis in young men. In the present study, the grivet monkey was established as an experimental model for such infection. A yolk sac suspension of C. trachomatis, immunotype K, was inoculated into the left spermatic cords of two monkeys. On days 7 and 14 postinoculation (pi), the left testis of each monkey was enlarged to twice its normal size. The epididymis and the spermatic cord on the same side were swollen and reddened. All layers of spermatic cord were infiltrated with lymphocytes and polymorphonuclear leukocytes, and the lumen, which was filled with an exudate, was reduced in diameter. The luminar epithelium was destroyed. The ducts of the left epididymis were filled with an inflammatory exudate. The epithelium was flattened, but there were no lesions. The seminiferous tubules of the left testis were normal, but edema and hyperemia were observed in the interstitial tissue. The right spermatic cord was inoculated with noninfected yolk sac suspension. On the right side, no inflammatory reactions were seen in the testis, the epididymis, or the spermatic cord. The monkeys had a yellowish discharge 7 to 14 days pi. Urethral smears revealed an preincubation values were found.

Animals↗
PubMed1990

Differential human serologic response to two 60,000 molecular weight Chlamydia trachomatis antigens.

Chlamydia trachomatis causes sexually transmitted diseases and is associated with serious long-term sequelae such as tubal infertility and ectopic pregnancy. There have been suggestions that chlamydial antigens of approximately 57,000-60,000 Mr may be involved in the immunopathology. Two important chlamydial antigens of 57,000-60,000 Mr are a Triton X-100-soluble antigen, which induces hypersensitivity in ocular models, and a sarcosyl-insoluble cysteine-rich structural protein, omp2. In this study, a 57,000 Mr Triton X-100-soluble protein was characterized as the chlamydial homolog of groEL, a heat shock protein. Using protein fractions, antibody responses of pelvic inflammatory disease (PID) and ectopic pregnancy patients to chlamydial groEL and omp2 were differentiated. Nearly all patients in both groups were reactive to omp2. Of those with titers greater than or equal to 1:512, 31% of PID sera and 81% of ectopic pregnancy sera were positive for chlamydial groEL (P = .004). This selectivity suggests that women with PID who develop chronic sequelae are those with antibody to groEL.

Antibodies, Bacterial↗
PubMedDate not supplied

[Chlamydiae. 2. Chlamydia trachomatis].

The Chlamydia trachomatis (C.t.) causes trachoma, inclusion conjunctivitis, lymphogranuloma venereum and it is the more frequent responsible of sexually transmitted infections; in fact, only in the United States, 3-4 million of people suffer from these infections each year. Besides, there are many secondary infections that may cause sterility in man and woman. Risk factors, for venereal infections owed to C.t., are related to the number of sexual partners, age, socioeconomics status and sexual preference. More frequently, the C.t. infects persons that begin sexual activity earlier, those who have many sexual partners and an higher level of education. The direct diagnosis for detecting C.t. can be performed with the citologic test, cell culture, direct immunofluorescence and enzyme immuno-assay. Although, the cell culture is the technique of choice, at present the immunofluorescence and enzyme immuno-assay are the methods preferred because of rapidity and esecution. The indirect diagnosis can be achieved by the complement fixation, indirect immunofluorescence and enzyme immuno-assay tests. In this case, excluding the complement fixation test not more reliable, the method of choice depends, above all, upon the kind of infection in progress. Tetracycline, erythromycin, rifampicin and cloramphenicol are considered the treatment of choice.

Adult↗
PubMed1996

[Comparison of polymerase chain reaction and ELISA in the diagnosis of Chlamydia trachomatis infection].

Chlamydia trachomatis (CT) is the most frequent cause of sexually transmitted disease in the western world. However, only a few cases have been reported from Israel. Because of the frequent absence of symptoms, its high prevalence, rapid spread, and the seriousness of complications, the quality of the diagnostic test for this microorganism is very important. Cell culture has always been regarded as the "gold standard" in diagnosis. However, factors such as collection, transport time and storage can negatively influence the sensitivity of culturing. We evaluated a polymerase chain reaction (PCR) assay (Amplicor CT, Roche Molecular Systems) for the detection of CT. CT-PCR was compared with a non-culture method (ELISA) in cervical, urethral and first-void urine specimens in 30 patients attending our sexually transmitted disease clinic. There were 16 males and 14 females; in 16 of them (53%) CT-PCR was positive. However, in only 6 of the latter (38%) was CT-ELISA also positive. 7 urine specimens from males with non-specific urethritis had a positive CT-PCR and a negative CT-ELISA. There were discrepancies between ELISA and the PCR test in 10 (3 females) of the 30. We confirm other studies indicating the PCR to be a highly sensitive assay for detecting CT infection from urogenital specimens. CT-PCR from first-void urine provides a noninvasive technique for routine screening of CT infection in both symptomatic and asymptomatic males and females.

Chlamydia Infections↗
PubMed1998

Trend in Chlamydia trachomatis infection among pregnant women in the past ten years in Japan: significance of Chlamydia trachomatis seroprevalence.

BACKGROUND AND OBJECTIVES: Chlamydia trachomatis infection is believed to be the most common bacterial sexually transmitted disease (STD) in industrialized countries. The objective of the current study was to assess the recent trend in the prevalence of C. trachomatis in Japan. GOAL OF THIS STUDY: To determine the trend in the seroprevalence for C. trachomatis among pregnant women in Nagasaki, Japan, during the past 10 years. STUDY DESIGN: The seroprevalence for C. trachomatis of 9,652 pregnant women of various ages screened in 1996 and 1997 was compared with those of 275 and 297 stocked samples from 1987 and 1992, respectively. Serum antibodies to C. trachomatis were detected by the enzyme immunoassay. Prospective samples of 33 seropositive cases were also analyzed to determine kinetics of the serum antibody titer. RESULTS: The seroprevalence has decreased in all age groups during the last 10 years. More than 70% of seropositive cases converted to be seronegative within 10 years. CONCLUSION: The prevalence of C. trachomatis has been decreasing among Japanese pregnant women.

Adult↗
PubMed1996

Sphingolipids and glycoproteins are differentially trafficked to the Chlamydia trachomatis inclusion.

Chlamydia trachomatis is an obligate intracellular pathogen that multiples within the confines of a membrane-bound vacuole called an inclusion. Approximately 40-50% of the sphingomyelin synthesized from exogenously added NBD-ceramide is specifically transported from the Golgi apparatus to the chlamydial inclusion (Hackstadt, T., M.A. Scidmore, and D.D. Rockey. 1995. Proc. Natl. Acad. Sci. USA. 92: 4877-4881). Given this major disruption of a cellular exocytic pathway and the similarities between glycolipid and glycoprotein exocytosis, we wished to determine whether the processing and trafficking of glycoproteins through the Golgi apparatus to the plasma membrane in chlamydia-infected cells was also disrupted. We analyzed the processing of several model glycoproteins including vesicular stomatitis virus G-protein, transferrin receptor, and human histocompatibility leukocyte class I antigen. In infected cells, the posttranslational processing and trafficking of these specific proteins through the Golgi apparatus and subsequent transport to the plasma membrane was not significantly impaired, nor were these glycoproteins found associated with the chlamydial inclusion membrane. Studies of receptor recycling from endocytic vesicles employing fluorescently and HRP-tagged transferrin and anti-transferrin receptor antibody revealed an increased local concentration of transferrin and transferrin receptor around but never within the chlamydial inclusion. However, Scatchard analysis failed to show either an increased intracellular accumulation of transferrin receptor or a decreased number of plasma membrane receptors in infected cells. Furthermore, the rate of exocytosis from the recycling endosomes to the plasma membrane was not altered in chlamydia-infected cells. Thus, although C. trachomatis disrupts the exocytosis of sphingolipids and the Golgi apparatus appears physically distorted, glycosylation and exocytosis of representative secreted and endocytosed proteins are not disrupted. These results suggest the existence of a previously unrecognized sorting of sphingolipids and glycoproteins in C. trachomatis-infected cells.

4-Chloro-7-nitrobenzofurazan↗
PubMed1995

Sample adequacy in detecting Chlamydia trachomatis.

OBJECTIVE: Chlamydia trachomatis is an important etiological agent in female genital infection and may result in infertility. In recent years rapid diagnostic methods have become widely used as alternatives to cell culture. Our objective was to evaluate the technique of direct fluorescence assay (DFA) in estimating the presence of C. trachomatis. METHODS: Specimens taken from 40 infertile and 20 fertile women were examined by DFA for the presence of C. trachomatis. RESULTS: Six of forty (15%) infertile women were found to be positive whereas no positive specimens were detected in the control group. When the specimens were grouped into those which were adequate or inadequate, 19 and five specimens, respectively, were adequate in the infertile and healthy groups. If only adequate specimens are included in estimating the presence of Chlamydia, the percentage is 31.6%. CONCLUSIONS: In order to use DFA as a more reliable and rapid diagnostic test of C. trachomatis in female genital infection, false-negativity must be eliminated. Specimens must be collected adequately and concentrated in order to achieve optimal diagnostic success.

Cervix Uteri↗
PubMed2004

Differential regulation of inflammatory cytokine secretion by human dendritic cells upon Chlamydia trachomatis infection.

Chlamydia trachomatis is an obligate intracellular gram-negative bacterium responsible for a wide spectrum of diseases in humans. Both genital and ocular C. trachomatis infections are associated with tissue inflammation and pathology. Dendritic cells (DC) play an important role in both innate and adaptive immune responses to microbial pathogens and are a source of inflammatory cytokines. To determine the potential contribution of DC to the inflammatory process, human DC were infected with C. trachomatis serovar E or L2. Both C. trachomatis serovars were found to infect and replicate in DC. Upon infection, DC up-regulated the expression of costimulatory (B7-1) and cell adhesion (ICAM-1) molecules. Furthermore, chlamydial infection induced the secretion of interleukin-1beta (IL-1beta), IL-6, IL-8, IL-12p70, IL-18, and tumor necrosis factor alpha (TNF-alpha). The mechanisms involved in Chlamydia-induced IL-1beta and IL-18 secretion differed from those of the other cytokines. Chlamydia-induced IL-1beta and IL-18 secretion required infection with viable bacteria and was associated with the Chlamydia-induced activation of caspase-1 in infected host cells. In contrast, TNF-alpha and IL-6 secretion did not require that the Chlamydia be viable, suggesting that there are at least two mechanisms involved in the Chlamydia-induced cytokine secretion in DC. Interestingly, an antibody to Toll-like receptor 4 inhibited Chlamydia-induced IL-1beta, IL-6, and TNF-alpha secretion. The data herein demonstrate that DC can be infected by human C. trachomatis serovars and that chlamydial components regulate the secretion of various cytokines in DC. Collectively, these data suggest that DC play a role in the inflammatory processes caused by chlamydial infections.

Caspase 1↗
PubMed2005

Mucosal immunization with recombinant MOMP genetically linked with modified cholera toxin confers protection against Chlamydia trachomatis infection.

Chlamydia trachomatis is a major human health pathogen due to its role in sexually transmitted diseases. Thus, there is a need to develop an effective vaccine at the mucosal surface against this pathogen. In an effort to develop a mucosal vaccine, a modified cholera toxin gene was genetically linked to the C. trachomatis MoPn NiggII MOMP gene to generate a recombinant protein with the mucosal adjuvant properties of the cholera toxin and immunological antigenicity of the chlamydial protein. The recombinant fusion protein (rMOMP) was expressed in E. coli, purified and analyzed by SDS-PAGE, immunoblot, and GM1-ELISA, and subsequently used to immunize BALB/c mice via intranasal (i.n.) and intravaginal (vag.) routes. The rMOMP protein administered via the i.n. route induced a higher concentration of anti-MOMP specific antibodies in both serum and vaginal washes as compared to mice immunized with Chlamydia or PBS. Antibody isotype analysis revealed that i.n. administration of rMOMP to mice induced higher concentrations of serum and vaginal wash IgA, IgG1, IgG2a, and IgG2b antibodies. Vaginal washes from all immunized mice following a chlamydial challenge infection were analyzed by indirect immunoflourescence to study the level of protection provided by various immunogens. Maximum protection against C. trachomatis as assessed by reduction in C. trachomatis inclusion forming units (IFU) was provided by i.n. immunization of mice with rMOMP. This is a first report using genetic fusion of cholera toxin and MOMP genes and provides a novel approach for the design and development of a mucosal vaccine against Chlamydia.

Administration, Intranasal↗