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PubMed1989

Identification of genus-specific epitopes on the outer membrane complexes of Chlamydia trachomatis and Chlamydia psittaci immunotypes 1 and 2.

Polyclonal and monoclonal antibodies were used to study the immunogenic and antigenic characteristics of chlamydiae. We focused on the most predominant proteins in the outer membrane complex, the major outer membrane protein (MOMP) and the doublet consisting of proteins of 57 and 62 kilodaltons (57-62 kDa doublet). Immunoblot analyses were performed with chlamydial elementary bodies by using (i) immune sera from sheep which had undergone a recent episode of abortion due to the ovine abortion (OA) strain of C. psittaci, (ii) rabbit hyperimmune anti-C. psittaci (OA) and -C. trachomatis sera, and (iii) monoclonal antibodies to the MOMP of C. trachomatis. The typical pattern of response with polyclonal antisera against heterologous elementary bodies was reactivity with the 57-62 kDa doublet and lipopolysaccharide with weak and sometimes no anti-MOMP activity. Three distinct genus-specific anti-C. trachomatis MOMP monoclonal antibodies showed different patterns of reactivity with the MOMPs of the two immunotypes of C. psittaci and C. trachomatis serovars. Our data confirm the predominance of a genus-specific 57-62 kDa doublet response despite the presence of genus-specific epitopes on the MOMP.

Animals↗
PubMed1996

A seroepidemiologic study of Chlamydia pneumoniae, Chlamydia trachomatis and Chlamydia psittaci in different populations on the mainland of China.

To evaluate and compare the prevalence of antibodies to 3 chlamydial species in various populations on the mainland of China, the MIF test was used to detect both serum IgG and IgM antibodies to these species in the normal population (n = 711), in poultry workers (n = 51), in female prostitutes (n = 106), in patients attending the sexually transmitted diseases clinic (n = 98), and in adult patients with pneumonia and bronchitis (n = 108). In the normal population, IgG antibodies against C. pneumoniae, C. trachomatis and C. psittaci were present in 61.5%, 9.3%, and 3.5%, respectively, and increasing with age. Prevalence and geometric mean titers (GMT) of IgG antibodies to C. trachomatis in prostitutes (54.7%) and female (55%), but not male (15.4%) sexually transmitted disease patients were significantly higher than in the normal adult female population. The prevalence indicating both previous and recent C. psittaci infections in poultry workers was no higher than in the others. The prevalence of IgG antibodies and GMT to C. pneumoniae in patients with pneumonia and bronchitis was not statistically higher than in the normal adult population. Evidence of cross-reactivities in the MIF test between different species was found in both prevalence and GMT. Serum IgM antibodies were usually absent in patients who met the serological criteria of recent C. pneumoniae infection, indicating that most of them could be considered as reinfections. On the basis of our survey, acute antibodies to C. pneumoniae by the MIF test, if they are detected, may be valuable in the diagnosis of recent C. pneumoniae infections.

Adolescent↗
PubMed2001

Screening for Chlamydia trachomatis infection using the BDProbeTec ET Chlamydia trachomatis amplified DNA assay on urine in a GUM clinic setting: a simple, fast and cost-effective alternative.

This study compared the BDProbeTec ET Chlamydia trachomatis amplified DNA assay on urine specimens with culture of genital swabs for the detection of C. trachomatis in patients attending the Department of Genitourinary Medicine (GUM), Cardiff Royal Infirmary. Almost twice as many patients tested positive by BDProbeTec ET than by culture. A similar difference was found for both males and females. The case notes of those patients positive by BDProbeTec ET alone were analysed and a significantly greater number were found to have risk indicators for C. trachomatis infection when compared with age and sex comparable controls, providing clinical validation of our findings. The BDProbeTec ET assay was easy to use, more importantly, the test format features an internal control integral with every sample. The cost per true positive was calculated as comparable with culture. We conclude that the BDProbeTec ET assay is a superior alternative to culture for identifying patients infected with C. trachomatis in the GUM clinic setting.

Chlamydia Infections↗
PubMed1998

Detection of Chlamydia trachomatis by the Gen-Probe AMPLIFIED Chlamydia Trachomatis Assay (AMP CT) in urine specimens from men and women and endocervical specimens from women.

Molecular biology-based amplification methods are significantly more sensitive than other methods for the detection of Chlamydia trachomatis. The performance characteristics of the new Gen-Probe AMPLIFIED Chlamydia Trachomatis Assay (AMP CT) with endocervical and urine specimens were compared to those of culture for patients attending two Baltimore City sexually transmitted disease clinics and a clinic for adolescents. AMP CT uses transcription-mediated amplification (TMA) and hybridization protection assay procedures to qualitatively detect C. trachomatis by targeting a 23S rRNA. Discrepant results between culture-negative and AMP CT-positive specimens were resolved by direct fluorescent-antibody staining of sedimented culture transport medium for elementary bodies and by TMA with 16S rRNA as a target. Following discrepant analysis, for 480 female urine specimens AMP CT had a sensitivity of 93.8% and a specificity of 100%. For 464 male urine specimens, the resolved sensitivity and specificity of AMP CT were 95.6 and 98.7%, respectively. For the 479 endocervical swab specimens the sensitivity of AMP CT was 100% and the specificity was 99.5%. Resolved culture sensitivities of AMP CT for female and male swab specimens were 52.3 and 58.9%, respectively. These results demonstrate that AMP CT is highly sensitive for the detection of C. trachomatis in endocervical specimens and in urine specimens from men and women.

Cells, Cultured↗
PubMed1994

[The prevalence of anti-Chlamydia trachomatis and anti-Chlamydia pneumoniae antibodies in Brazzaville].

The prevalence study of antibodies to Chlamydia trachomatis and Chlamydia pneumoniae in Brazzaville were screened from 108 women (56 pregnant women, 18 infertile women and 34 women affected with genital tract infections) and 108 blood donors (control subjects) by indirect microimmunofluorescent assay. 57.4% of studied women were carrying Chlamydia trachomatis antibodies, and 51.8% had C. pneumoniae antibodies. Prevalence of Chlamydia antibodies by women group studied was estimated to be: in pregnancy women group 51.7% of C. trachomatis antibodies and 62.5% of C. pneumoniae antibodies; in infertile women group 61.1% of C. trachomatis antibodies and 33.3% of C. pneumoniae antibodies; in women affected with genital tract infections group: 64.7% of C. trachomatis antibodies and 44.1% of C. pneumoniae antibodies. In blood donors group, the prevalence of IgG antibodies against Chlamydia trachomatis is 27.7% and 37% for IgG antibodies against C. pneumoniae.

Adolescent↗
PubMed2005

Up-regulation of the JAK/STAT1 signal pathway during Chlamydia trachomatis infection.

Chlamydia trachomatis infection is the most common cause of sexually transmitted disease, leading to female pelvic inflammatory disease and infertility. The disease process has been linked to cellular response to this bacterial pathogen. This obligate intracellular pathogen infects macrophages, fibroblast cells, and epithelial and endothelial cells. We show in this study that infection of cervical epithelial cells, the primary target of Chlamydia trachomatis, leads to up-regulation and activation of the JAK/STAT signal pathway. Specifically, Chlamydia trachomatis infection of HeLa 229 cells selectively induces STAT1, STAT2, and IFN-stimulated transcription factor 3gamma expression and promotes STAT1 activation. The up-regulation of STAT1 is dependent on bacterial replication, because treatment of infected cells with antibiotics prevents STAT1 up-regulation. By analysis of the gene transcriptional and cytokine expression profiles of host cells combined with the use of neutralizing Abs, we show that IFN-beta production is critical for STAT1 induction in epithelial cells. Finally, we demonstrate that the host up-regulates STAT1 to restrict bacterial infection, because Chlamydia propagates more efficiently in STAT1-null or STAT1 knockdown cells, whereas Chlamydia growth is inhibited in cells with up-regulated STAT1 expression. This study demonstrates that the infected cells up-regulate the host innate antimicrobial response to chlamydial infection. It also highlights the importance of cellular response by nonimmune cells in host clearance of chlamydial infection.

Cell Line, Tumor↗
PubMed2000

Genome sequences of Chlamydia trachomatis MoPn and Chlamydia pneumoniae AR39.

The genome sequences of Chlamydia trachomatis mouse pneumonitis (MoPn) strain Nigg (1 069 412 nt) and Chlamydia pneumoniae strain AR39 (1 229 853 nt) were determined using a random shotgun strategy. The MoPn genome exhibited a general conservation of gene order and content with the previously sequenced C.trachomatis serovar D. Differences between C.trachomatis strains were focused on an approximately 50 kb 'plasticity zone' near the termination origins. In this region MoPn contained three copies of a novel gene encoding a >3000 amino acid toxin homologous to a predicted toxin from Escherichia coli O157:H7 but had apparently lost the tryptophan biosyntheis genes found in serovar D in this region. The C. pneumoniae AR39 chromosome was >99.9% identical to the previously sequenced C.pneumoniae CWL029 genome, however, comparative analysis identified an invertible DNA segment upstream of the uridine kinase gene which was in different orientations in the two genomes. AR39 also contained a novel 4524 nt circular single-stranded (ss)DNA bacteriophage, the first time a virus has been reported infecting C. pneumoniae. Although the chlamydial genomes were highly conserved, there were intriguing differences in key nucleotide salvage pathways: C.pneumoniae has a uridine kinase gene for dUTP production, MoPn has a uracil phosphororibosyl transferase, while C.trachomatis serovar D contains neither gene. Chromosomal comparison revealed that there had been multiple large inversion events since the species divergence of C.trachomatis and C.pneumoniae, apparently oriented around the axis of the origin of replication and the termination region. The striking synteny of the Chlamydia genomes and prevalence of tandemly duplicated genes are evidence of minimal chromosome rearrangement and foreign gene uptake, presumably owing to the ecological isolation of the obligate intracellular parasites. In the absence of genetic analysis, comparative genomics will continue to provide insight into the virulence mechanisms of these important human pathogens.

Animals↗
PubMed1997

Polymerase chain reaction (PCR) detection of porcine Chlamydia trachomatis and ruminant Chlamydia psittaci serovar 1 DNA in formalin-fixed intestinal specimens from swine.

In previous studies chlamydiae were detected immunohistologically in the gut of 66 out of 311 pigs. The aim of the present investigation was the classification of these intestinal porcine chlamydiae. For the study, DNA extracted from 52 paraffin-embedded intestinal tissues was amplified in nested polymerase chain reactions (PCRs) with Chlamydia omp1 genus- and species-specific primers. Some of the amplification products were cloned and sequenced. In 45 cases DNA could be amplified with genus-specific primers. Species-specific PCR and sequencing showed that in 42 cases the chlamydial omp1 genotype was Chlamydia trachomatis. Sequenced DNA fragments were 95-99% identical with the porcine strain S45. In three further cases sequencing analysis provided DNA sequences which were 100% identical with Chlamydia psittaci B577 (serovar 1) omp1 genotype. So far as the authors are aware this is the first report on the occurrence of C. psittaci serovar 1 in pigs.

Animals↗
PubMed1997

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

The 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 University Hospital Rotterdam, Rotterdam, The Netherlands, by comparing the results to those of cell culture. From February 1996 to July 1996, urine samples for the AMP-CT test and urethral swabs for cell culture were collected from 544 men, while cervical swabs from 456 women were also taken for cell culture. Positive test results were obtained for 130 (13%) of the patients. AMP-CT test and cell culture results were discordant for 70 (7%) specimens. Analysis of the samples with discordant results was performed by an in-house PCR. After resolution of the discordant results, the sensitivity, specificity, and positive and negative predictive values of the AMP-CT test were 84.3, 98.8, 89.6, and 98%, respectively, for samples from females and 100, 99.2, 93.1, and 100%, respectively, for samples from males, while for cell culture these values were 72.5, 99.2, 92.5, and 98%, respectively, for samples from females and 57.4, 99.0, 86.1, and 95.4%, respectively, for samples from males. We conclude that the AMP-CT test is a fast and reliable test for the detection of C. trachomatis in urine specimens from females and, in particular, males.

Bacteriuria↗
PubMed1993

Comparison of the major outer-membrane protein (MOMP) gene of mouse pneumonitis (MoPn) and hamster SFPD strains of Chlamydia trachomatis with other Chlamydia strains.

Restriction fragments containing the major outer-membrane protein (MOMP) gene from two nonhuman (rodent) strains of Chlamydia trachomatis, the mouse pneumonitis (MoPn) strain and the SFPD strain isolated from hamsters with transmissible proliferative ileitis, were cloned and sequenced. The MOMP genes of both MoPn and SFPD encode an identical 22-amino acid leader peptide and mature polypeptides of 365 and 382 amino acids, respectively. Alignment of the MOMP genes of the two rodent strains revealed 91% identity. By comparison with other known chlamydial MOMP gene sequences, there was 80%-83% identity with human biovars strains of C. trachomatis, and there was 69%-70% identity with C. psittaci and C. pneumoniae strains. The main differences in these sequences were clustered into four variable domains. A minimum-length evolutionary tree was constructed on the basis of the MOMP gene variable positions by using PIMA package software. The minimum mutation distances indicated that (i) the MOMP genes of all chlamydial strains may have evolved from a common ancestor; (ii) all the strains of C. trachomatis compose one of the subtrees, and strains of C. psittaci and C. pneumoniae compose the other subtree; and (iii) in the C. trachomatis subtree, the human and the rodent strains are divided into two clusters. The branching pattern of this evolutionary tree is generally consistent with current classification based on serological, morphological, and other biological characteristics.

Amino Acid Sequence↗
PubMed1993

[Infection rate of Chlamydia trachomatis in sexual partners from pregnant women with Chlamydia trachomatis infection].

We investigated the infection rate of Chlamydia trachomatis in sexual partners who had pregnant wives with C. trachomatis diagnosed by means of serum-antibody test (Ipazyme) or antigen test (Chlamydiazyme, IDEIA-chlamydia). Antibody-positive rate was 60.4% (90/149 cases), and antigen-positive rate was 7.4% 11/149 cases). All cases with Chlamydial antigen had anti-Chlamydial antibody. Eleven cases with Chlamydial antigen had no symptom of urethritis. Among these cases, eight cases had abnormal laboratory findings. However, the other three cases who had no abnormal finding were careers of C. trachomatis. In this study, sexual partners who had Chlamydial antigen were few, however, those who had anti-chlamydial antibody were many. Therefore, C. trachomatis will disseminate among many families as a latent infection.

Adult↗
PubMed2005

[Advances in the treatment of Chlamydia trachomatis infection].

Chlamydia trachomatis may cause trachoma, pneumonia, urogenital infection, conjunctivitis and lymphogranuloma venereum, etc. This paper reviews the effects of monotherapy, combined antibiotic regimens, and drug resistance during the treatment of Chlamydia trachomatis infection.

Anti-Bacterial Agents↗
PubMed1995

[A study on the role of Chlamydia trachomatis in chronic prostatitis--analysis of anti-Chlamydia trachomatis specific IgA in expressed prostate secretion by western-blotting method].

Opinion among researchers is divided as to whether Chlamydia trachomatis is the causative organism of chronic prostatitis. In this study, using enzyme immuno assay, we examined the positive rate of anti-C. trachomatis IgA according to the leukocyte count in expressed prostate secretion (EPS), in a total of 169 patients including 92 patients who showed chronic prostatitis-like symptoms. And we confirmed, by western-blotting, the presence or absence of anti-heat shock protein (HSP: 60 KDa) IgA in EPS, and we investigated the role of C. trachomatis in chronic prostatitis. The total positive rate of anti-C. trachomatis IgA in EPS was 26.0% (44/169). According to the leukocyte count in EPS, the positive rate for the group with more than 10 WBC/hpf was 29.0% (20/69), for the group with 5-9 WBC/hpf was 37.9% (11/29), for the group with less than 5 WBC/hpf was 18.3% (13/71). Accordingly the positive rate of anti-C. trachomatis IgA in EPS was not higher in direct correlation to the severity of the inflammation at the infected site (p = 0.09). But the positive rate for the group with more than 5 WBC/hpf was higher than for the group with less than 5 WBC/hpf. On the other hand, the total positive rate of anti-HSP IgA in EPS was 17.6% (6/34), and according to the leukocyte count in EPS, the positive rate for the group with more than 10 WBC/hpf was 38.5% (5/13), for the group with 5-9 WBC/hpf was 0% (0/12). Accordingly the positive rate of anti-HSP IgA in EPS was higher in direct correlation to the severity of the inflammation at the infected site (p = 0.13). From this results, it was suggested that C. trachomatis was concerned with 29.0% (20/69) of chronic prostatitis with more than 10 WBC/hpf, and also C. trachomatis is the causative organism of chronic prostatis.

Antibody Specificity↗
PubMed1998

[Chlamydia trachomatis infections].

Chlamydia trachomatis is the most common bacterial cause of sexually transmitted disease in the developed countries. The most important implications of genital chlamydia infections involve the reproductive health sequalae of upper genital tract infections in women: pelvic inflammatory disease, ectopic pregnancy, and infertility, infection by this organism is insidious, symptoms are absent or minor among most infected women and many man. This large group of asymptomatic and infectious persons sustains transmission within a community. This review discusses the epidemiology, of sexually transmitted chlamydial infections, the spectrum of clinical manifestations and their sequelae, the laboratory diagnosis of genital chlamydiasis, antibiotic treatment and prevention.

Anti-Bacterial Agents↗
PubMed1994

The ophthalmologist's role in Chlamydia trachomatis infection.

Chlamydia Trachomatis (C.T.) most commonly causes cervicitis in women, often without overt symptoms; when untreated, it produces a clinically inapparent but persistent mild infection or an evident salpingitis. Either processes may lead to scarring of the falloppian tubes and fertility problems. A group of 30 women 20-35 years aged has undergone an ophthalmological routine examination; 7 of them presented a chronical follicular conjunctivitis and history of yellow-white cervical discharge, while the remaining 23 had a mild chronical follicular conjunctivitis but not genital symptoms. Each patient has undergone an immunofluorescent test with monoclonal antibody specific for C.T. on the samples collected by genital and conjunctival scraping and cytological evaluation of the above samples with Giemsa staining. 6 out of 7 patients with genital discharge were positive for C.T., one of which even for eye samples too; all eyes samples showed lymphomonocytes and neutrofilic cells in their eye samples. An additional 3 cases negative for C.T. showed this kind of cells in the eye scraping. The preliminary results of this study on mild follicular chronical conjunctivitis suggest that the Ophthalmologist could play an important role in order to make an early diagnosis in genital and eye infection by Chlamydial Trachomatis.

Adult↗