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PubMed2000

In vitro activity of GAR-936 against Chlamydia pneumoniae and Chlamydia trachomatis.

We evaluated the in vitro activity of GAR-936, a novel glycylcycline antibiotic, against ten isolates of Chlamydia pneumoniae and five strains of C. trachomatis. Susceptibility testing was done in HEp-2 cells. The MIC90s and MBC90s of GAR-936, doxycycline, ofloxacin and clarithromycin against C. pneumoniae were 0.125, 0.25, 0.25 and 0.06 mg/l, respectively. The MICs and MBCs of GAR-936, doxycycline, ofloxacin and clarithromycin against C. trachomatis were 0.03-0.125, 0.25, 0.25-0.5 and 0.06 mg/l, respectively. GAR-936 had excellent activity against both chlamydial species and may have a potential role in the treatment of human chlamydial infection.

Adult↗
PubMed2003

Imiquimod does not affect shedding of viable chlamydiae in a murine model of Chlamydia trachomatis genital tract infection.

OBJECTIVE: We postulated that either oral or vaginal administration of the immune response modifier imiquimod would decrease vaginal shedding of Chlamydia trachomatis, mouse pneumonitis strain (MoPn), in a murine model. METHODS: Female BALB/c mice were infected intravaginally with C. trachomatis (MoPn) and were administered imiquimod either orally (30 mg/kg) or vaginally (10 microl of 5% imiquimod cream) prior to infection and every second day after infection for a total of four doses. The course of infection was monitored by collecting cervical-vaginal swabs and isolation in HeLa 229 cell culture. To determine whether the drug affected T helper type 1 or T helper type 2 immune response polarization, immunoglobulin G (IgG) subclass antibody responses were assessed at day 56 after infection. RESULTS: There was no significant difference in the course of infection when imiquimod-treated mice were compared with sham-treated controls, regardless of whether the drug was administered orally or vaginally. IgG subclass antibody responses, and by extension, T helper type 1 to T helper type 2 immune response polarization, were also unaffected. CONCLUSIONS: Imiquimod has no efficacy in controlling C. trachomatis (MoPn) infection in the murine model.

Adjuvants, Immunologic↗
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↗
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↗
PubMed1993

Assessment of Chlamydia trachomatis-specific IgA and IgG serum antibodies in genitourinary Chlamydia trachomatis infection--comparative study between HITAZYME and IPAzyme.

We assessed the C. trachomatis antibody assay kit HITAZYME (Hitachi Chemical Co., Ltd.) using clinical specimens. This kit is based on an enzyme immunoassay (EIA) which utilized purified Chlamydia trachomatis outer membrane antigen as the solid phase antigen. Twenty-nine untreated male urethritis patients, 816 pregnant housewives, 188 cervicitis patients, and 76 pelvic inflammatory disease patients were tested. Agreement between the HITAZYME test and antigen detection in infected area was assessed, and a comparison was made with IPAzyme (a commercially available indirect immunoperoxidase assay kit). 1) Summary of HITAZYME and IPAzyme IgA: Agreement between the two assays was relatively good, i.e., 82.6% (916/1109). However, 5.5% (61/1109) were HITAZYME (-), IPAzyme (+), and 11.9% (132/1109) were HITAZYME (+), IPAzyme (-). Thus, in quite a few cases the results did not agree. IgG: Agreement between the two assays was 73.7% (817/1109). Agreement was relatively low, 24.4% (271/1109) were HITAZYME (-), IPAzyme (+). 2) In the cases of disagreement, more specific Western blot analysis was performed to check the reactivity of the anti-C. trachomatis antibody. When IgA was used, agreement between HITAZYME and Western blot analysis was 69.6% (16/23), and agreement between IPAzyme and Western blot analysis was 30.4% (7/23), whereas when IgG was used, agreement between HITAZYME and Western blot analysis was 80.0% (12/15), and agreement between IPAzyme and Western blot analysis was 20.0% (3/15). There was significantly greater agreement with HITAZYME than with IPAzyme. In other words, HITAZYME had greater specificity when reacted with C. trachomatis antigen than IPAzyme. 3) The IgA antibody-positive rate in antigen (+) cases (male urethritis: 72.7%, pregnant housewives: 65.7%, cervicitis: 70.3%, pelvic inflammatory disease: 70.0%) was significantly (p < 0.01) higher than in antigen (-) cases (male urethritis: 16.7%, pregnant housewives: 13.6%, cervicitis: 22.6%, pelvic inflammatory disease: 30.4%). Therefore, IgA antibody can serve as a suitable indicator for active infection. 4) The IgG antibody-positive rate in antigen (-) female cases was 15.5% using HITAZYME and significantly (p < 0.01) lower than with IPAzyme. HITAZYME had greater specificity than IPAzyme. In conclusion, HITAZYME has relatively good sensitivity and specificity. Moreover, since it is an EIA assay, it allows objective evaluation of results. It permits processing of a large number of specimens because it is easy to perform. Thus, HITAZYME is a superior antibody assay for C. trachomatis. It can be used when antigen tests are difficult to perform. It is strongly anticipated that HITAZYME will be able to be used clinically as a screening test.

Chlamydia Infections↗
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↗
PubMed1989

In vitro susceptibilities of Chlamydia pneumoniae (Chlamydia sp. strain TWAR).

The in vitro susceptibilities of two clinical isolates of Chlamydia pneumoniae from Brooklyn, N.Y., were determined for tetracycline, erythromycin, sulfamethoxazole, ciprofloxacin, and three new macrolides--azithromycin, clarithromycin, and roxithromycin. Clarithromycin was the most active drug tested, followed by the other macrolides, tetracycline, and ciprofloxacin.

Anti-Bacterial Agents↗
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↗
PubMed1999

[Chlamydia trachomatis infection in male infertility--the clinical usefulness of the detection of antibodies against Chlamydia trachomatis].

BACKGROUND: The objective of this study is to investigate the clinical usefulness of the detection of antibodies against Chlamydia trachomatis (C. trachomatis) in potential male infertility patients. PATIENTS AND METHODS: Analysis of serum samples for the presence of antibodies against C. trachomatis by enzyme immunoassay was performed in 83 male infertility patients. RESULTS: Immunoglobulin A (IgA) and G (IgG)-antibodies against C. trachomatis were found in 16 and 10 of 83 serum samples (19.3 and 12.0%) respectively. IgA and/or IgG-antibodies against C. trachomatis were found in 20 of 83 serum samples (24.1%). Serum IgA, IgG, or IgA and/or IgG positive patients showed increased semen and urine leukocytes numbers and reduced semen volume and sperm numbers, compared with negative patients, respectively, although these effects are not statistically significant. By Spearman's correlation analysis, however, significant positive correlations with serum IgA or IgG antibody index were found in semen and urine leukocytes numbers. Significant negative correlations with serum IgA antibody index was found in semen volume. In serum IgA positive patients, only 1 of 8 first-voided urine samples was positive for C. trachomatis-DNA by PCR. Moreover, the positive rates of surum IgA antibody and cervical antigen in the 8 female partners of IgA positive patients were only 25% (2 of 8 serum samples) and 12.5% (1 of 8 cervical specimens) respectively. CONCLUSION: There was a high prevalence (24.1%) of serum IgA and/or IgG-antibodies against C. trachomatis from infertility patients. The existance of antibodies against C. trachomatis in serum samples possibly influence semen quality, suggesting that C. trachomatis infection may play an important role in male infertility.

Adult↗
PubMed2001

[Evaluation of incidence of Chlamydia trachomatis infections among the group of infertile women diagnosed by laparoscopy, and based on properties of Chlamydia trachomatis in the cervical canal, peritoneal fluid and ovarian cyst puncture].

The number of 75 patients who underwent diagnostic et operative laparoscopy was analysed. The percentage of infection cases caused by Chlamydia Trachomatis was 9.33% investigations proved correlation between fallopian tube factor and infection. It seems that pelvic infection not always undergoes with infection of uterine cervix.

Adult↗
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↗
PubMed1988

[Chlamydia diagnosis in clinical practice. Chlamydia trachomatis EIA and direct immunofluorescence (MikroTak) in comparison with cell culture].

The correct obtaining of material is decisive for microbiological diagnosis. The new immunologic methods, enzyme immunoassay (Chlamydiazyme) and the direct immunofluorescence with monoclonal antibodies (MikroTrak) for the detection of Chlamydia trachomatis have several advantages over cell culture. In 457 tests of urethral smears from men with all 3 methods, sensitivity and specificity were compared with cell cultures as method of reference. Tests with Chlamydiazyme yielded a concordance of 87.1%, a sensitivity of 81.5% and an specificity of 87.8%. Tests with MikroTrak were almost identical with a concordance of 86.9%, a sensitivity of 81.3% and a specificity of 87.5%. With both methods, the positive predictive value with 43.8% and 43.3% respectively is low. Frequent positive results with the immunological methods, which could not be verified by cell cultures, must be interpreted as failure of the culture method under practice conditions. The correlation of results with the clinical course supports this assumption.

Adult↗
PubMed1979

[A method for the preparation of a Chlamydiae group-specific antigen on hela-229 cells infected with a strain of "Chlamydia trachomatis" for use in the complement fixation test (author's transl)].

A simple method for the preparation of a potent group-specific antigen on HeLa-229 cells infected with MRC-1 (LB) (TRIC/GB/MRC-1 Gf) strain of Chlamydia trachomatis is outlined. HeLa-229 cells are infected (MRC-1 strain, 102 inclusion-forming units per cell) with centrifugation at 4,000 g for 1 h in flat-bottomed vials. The cells are removed by brief trypsinization with 0.25% trypsin and put into 75 cm2 culture flasks (12 x 106 cells by flask) in BHK-21 medium supplemented with foetal bovine serum. The flasks are incubated for 5 days at 37 degrees C. The destroyed cell monolayer and the supernatant are centrifuged at 100,000 g for 1 h. The pellet is collected and resuspended in PBS and subjected to ultrasonic vibration for 30 min. This antigen may be used for detection of complement-fixing antibodies in lymphogranuloma venereum and ornithosis.

Antigens, Bacterial↗
PubMed1993

Antigenic analysis of Chlamydia pecorum and mammalian Chlamydia psittaci by use of monoclonal antibodies to the major outer membrane protein and a 56- to 64-kd protein.

Monoclonal antibodies were prepared against 40- and 56- to 64-kd antigens of Chlamydia pecorum strain Maeda, which was isolated from a cow with pneumonia. Using the monoclonal antibodies, 5 strains of C pecorum, 25 strains of mammalian and 19 strains of avian C psittaci, 1 strain of C pneumoniae, and 3 strains of C trachomatis were analyzed for immunologic reactivity by use of the indirect immunofluorescent test. Monoclonal antibody analysis revealed immunologic relatedness between C pecorum and mammalian strains of C psittaci, which were completely differentiated from the other avian strains. Bovine strains were distinguished from ovine strains. Antigenic diversity was observed for bovine and ovine strains. Feline- and guinea pig-derived strains were shown to be immunologically different from bovine and ovine strains. Results provide the basis for typing and epidemiologic study of bovine and ovine strains of C pecorum and C psittaci.

Animals↗
PubMed2002

Upregulation of extracellular matrix metalloproteinase inducer (EMMPRIN) and gelatinases in human atherosclerosis infected with Chlamydia pneumoniae: the potential role of Chlamydia pneumoniae infection in the progression of atherosclerosis.

Chlamydia pneumoniae infection implicated as an important etiologic factor of atherosclerosis, especially in coronary artery disease (CAD), was found in vitro to be associated with the induction of matrix metalloproteinases (MMPs). An extracellular matrix metalloproteinase inducer (EMMPRIN)/ membrane-type 1 matrix metalloproteinase (MT1-MMP) system which induces and activates MMPs, is suggested to be functional and were upregulated in the failing myocardium. However, the upstream regulation of MMPs by C. pneumoniae within atheroma itself remains unclear. We evaluated the seroepidemiologic study of C. pneumoniae infection in CAD patients (n= 391) and controls (n=97) and performed histopathological and in vitro analysis in atherosclerotic vascular tissues obtained from patients with seropositive to C. pneumoniae (n=20), by using immunochemistry for C. pneumoniae, EMMPRIN/MT1-MMP, MMP-2, and MMP-9. The seropositive rates of both anti-C. pneumoniae IgG and IgA were 56.7% in CAD group and 43.3% in control group (P=0.033). Seropositive rate was increased in subgroups of CAD patients without conventional coronary risk factors compared to those with conventional risk factors. Immunoreactivities of EMMPRIN, MT1-MMP, MMP-2, and MMP-9 were increased in the atheromatous plaque itself, predominantly in immunoreactive macrophages/mononuclear cells to C. pneumoniae. Furthermore, Western blot analysis showed that EMMPRIN and MMP-2 were detected more prominently in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. Zymographic analysis revealed that activities of MMP-2 and MMP-9 were more increased in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. The present study demonstrated upstream regulation of MMPs can be induced by C. pneumoniae within atheromatous plaque itself. These findings help to understand the potential role of C. pneumoniae in the progression of atherosclerosis.

Aged↗
PubMed1991

A heat-labile protein of Chlamydia trachomatis binds to HeLa cells and inhibits the adherence of chlamydiae.

From highly purified elementary bodies (EBs) of Chlamydia trachomatis, we have identified a protein of 38 kDa that selectively binds to monolayer cultures of HeLa cells. This protein, which we have named the chlamydial cytadhesin (CCA), is present on the surface of the EBs of three C. trachomatis serovars (B, E, and L1) that were examined. Localization of the CCA at the surface was confirmed by its ability to be labeled when viable EBs were iodinated and by its absence in preparations from trypsin-treated EBs. Viable EBs, but not heated or trypsin-treated EBs, inhibited the binding of the CCA to HeLa cells, indicating competition for a common receptor on the host cell membrane. A dose-dependent inhibition of adherence of radioactive EBs to HeLa cells was effected by extracts containing the CCA. This inhibition occurred even with extracts prepared from the EB of heterologous serovars. However, no inhibition could be demonstrated with extracts prepared from heat-treated EBs. Heat treatment of the extract resulted in the loss of ability of the CCA to bind to the host cells. HeLa cells preincubated with CCA-containing chlamydial extract showed reduced ability to bind labeled EBs and to develop cytoplasmic inclusions after infection. This protective activity was lost after exposure of the extract to heat. These findings indicate that the CCA is a thermolabile surface-exposed chlamydial adhesin; it may be useful in the development of vaccines for diseases caused by the pathogenic bacterium.

Bacterial Adhesion↗
PubMed2001

Pooling of Chlamydia laboratory tests to determine the prevalence of ocular Chlamydia trachomatis infection.

With the Global Elimination of Trachoma by 2020 program underway, it has become increasingly important to identify the prevalence of ocular chlamydia infection in communities. DNA amplification tests are the gold standard, but are prohibitively expensive. In the present paper, we investigate whether pooling multiple specimens into a single test is feasible. The conjunctivae of 170 children in western Nepal were examined and swabbed. The prevalence of chlamydial infection was estimated in two ways using the ligase chain reaction: by testing all 170 specimens individually, and by testing 34 pools of 5 specimens each. We show that the confidence interval for 34 pooled specimens approaches that of doing all 170 specimens as the prevalence decreases. We also determine the optimal number of specimens to pool into a single test to minimize the confidence interval of the estimate. If the population prevalence is expected to be around 10%, then 14 specimens should be pooled per test. Even at 50% prevalence, costs can be reduced by pooling two samples per test.

Child↗
PubMed1979

Host modification of chlamydiae: presence of an egg antigen on the surface of chlamydiae grown in the chick embryo.

Egg-grown chlamydiae (EGO) have a yolk sac antigen assoicated with their surface which is absent from cell monolayer-grown organisms (CGO). EGO infectivity was specifically neutralized by rabbit antiserum to normal yolk sac; CGO infectivity, before or after incubation with normal yolk sac material, was not neutralized. Treatment of EGO with Clostridium welchii culture filtrate, containing phospholipase C, abolished spontaneous infectivity for monolayers and neutralization by anti-yolk sac antiserum but did not affect centrifuge-assisted infectivity. The possible significance of host antigen on the chlamydial surface is considered.

Animals↗