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At least 19 recordsLinked to original sources
PubMed1990

Detection and differentiation of Chlamydia trachomatis, Chlamydia psittaci, and Chlamydia pneumoniae by DNA amplification.

The polymerase chain reaction was used to detect major outer membrane protein (MOMP) gene sequences from the three species of Chlamydia. Using three primer pairs and one restriction enzyme digestion, three distinct genotypes, corresponding to the three species, Chlamydia trachomatis, Chlamydia pneumoniae, and Chlamydia psittaci, were demonstrated. C. trachomatis was amplified by all three primer pairs and the amplified fragment was digested by EcoRI. C. pneumoniae was amplified by only two of the three primer pairs, and the amplified fragment was digested by EcoRI. C. psittaci was amplified by only two of the pairs and the amplified fragment was EcoRI-resistant. C. trachomatis was detected in direct patient specimens, tissue culture specimens, and fixed specimens, and all serovars of C. trachomatis were detectable. The polymerase chain reaction can detect and differentiate the three species of Chlamydia and may prove a valuable diagnostic tool.

Bacterial Outer Membrane Proteins↗
PubMed1992

PCR detection and differentiation of Chlamydia pneumoniae, Chlamydia psittaci and Chlamydia trachomatis.

A PCR-based system was developed for the detection and differentiation of Chlamydia trachomatis, Chlamydia psittaci and Chlamydia pneumoniae. A conserved 145 bp fragment of the chlamydial omp1 gene was amplified from all three species. The three species were then differentiated from each other by digestion of this PCR product with restriction enzymes Eco RI and either Hind III or Pst I. The system was shown to work for two strains of C. pneumoniae, 11 strains of C. psittaci and 10 serovars of C. trachomatis, and had a sensitivity of less than 10 chlamydial elementary bodies. This method was also applicable to the detection of C. trachomatis in conjunctival and nasopharyngeal swabs.

Adult↗
PubMedDate not supplied

Detection of IgM antibodies to Chlamydia trachomatis, Chlamydia pneumoniae, and Chlamydia psittaci from Japanese infants and children with pneumonia.

Chlamydia trachomatis (C. trachomatis) is now well established as a pathogen of neonatal inclusion conjunctivitis and infantile pneumonia. C. pneumoniae (TWAR) and C. psittaci also cause pneumonia and other respiratory infections. Serum samples from 223 Japanese infants and children with pneumonia were tested for IgM antibodies to C. trachomatis, C. pneumoniae and C. psittaci. IgM antibodies to C. trachomatis were measured by an enzyme immunoassay (EIA) and by a microimmunofluorescence (MIF) test. IgM antibodies to C. pneumoniae and C. psittaci were determined by MIF. Of 223 patients, 48 (21.5%) were positive for IgM antibodies to C. trachomatis, 11 (4.9%) were positive for C. pneumoniae and 5 (2.2%) were positive for C. psittaci. From nasopharyngeal swabs collected from 87 infants with pneumonia (0 to 1 year of age), we attempted to isolate C. trachomatis with tissue culture. C. trachomatis was isolated from 23 (26.4%) of 87 infants with pneumonia, and IgM antibodies to C. trachomatis were detected in 17 (19.5%) of them. Our data suggest a role for chlamydial infection in childhood pneumonia beyond infancy with both C. trachomatis and C. pneumoniae being contributing pathogens.

Adolescent↗
PubMed1992

[An isolation procedure of Chlamydia pneumoniae and Chlamydia trachomatis].

The author devised a method which permits simultaneous isolation and identification of Chlamydia using a slide chamber with 8 wells. Contaminating bacteria were eliminated by filtration with the membrane filter. The procedure allowed isolation of Chlamydia pneumoniae and Chlamydia trachomatis from 11 (10.1%) out of 109 and 10 (9.2%) out of 109 otolaryngologic clinical specimens, respectively. The use of HL cells together with Hela-229 cells had been considered essential to isolate Chlamydia from specimens in this field. The conditions for isolating Chlamydia pneumoniae were similar to those for Chlamydia trachomatis. The slide chamber procedure with membrane filter treated specimens was suitable for simultaneous isolation and culture of various species of Chlamydia and allowed easy differentiation of Chlamydia pneumoniae from Chlamydia trachomatis with identification by the indirect fluorescent-antibody technique. Routine examination of clinical specimens using this procedure should be required in the future in order to better understand chlamydial infections.

Bacteriological Techniques↗
PubMedDate not supplied

Chlamydia immunoreactivity in birds with psittacosis: localization of chlamydiae by the peroxidase-antiperoxidase method.

Diagnosis of psittacosis (infection with Chlamydia psittaci) has traditionally been dependent upon culture or demonstration of chlamydiae in tissues by cytochemical stains such as the Gimenez or Macchiavello's stain. In this study, a peroxidase-antiperoxidase (PAP) technique that employs a commercially available monoclonal antibody directed against Chlamydia is used to demonstrate chlamydiae in the necropsy tissues of nine birds. Chlamydiae were identified in air sacs (83%), liver (78%), spleen (78%), small intestines (67%), large intestines (44%), and kidneys (33%). Usually chlamydiae were associated with microscopic lesions, but in 75% of large intestines examined, organisms were identified within the lumen of histologically normal intestine. PAP studies revealed numerous chlamydiae that were inapparent in hematoxylin-and-eosin-stained sections. These results demonstrate the utility and sensitivity of the PAP method in the identification of chlamydiae in microscopic sections.

Animals↗
PubMed1986

Both species of chlamydia and two biovars of Chlamydia trachomatis stimulate mouse B lymphocytes.

We have investigated the ability of both species of chlamydiae (C. trachomatis and C. psittaci), two major biovars of C. trachomatis (lymphogranuloma venereum and trachoma), and the two developmental forms of chlamydia (reticulate and elementary bodies) to stimulate murine spleen lymphocytes. All of these forms of the bacteria induce potent proliferation and differentiation to plaque-forming cells by B lymphocytes in vitro. Chlamydiae induce a broad antibody response, suggesting that stimulation is polyclonal in nature. Although all chlamydiae possess a lipopolysaccharide (LPS) genus-specific molecule similar to LPS found on Re mutant enterobacteria, polyclonal B cell stimulation is likely caused by molecules other than LPS, since i) polymyxin B failed to inhibit chlamydia-induced immunostimulation and ii) C3H/HeJ mice (LPS nonresponders) produced normal numbers of PFC after culture with chlamydia (but not LPS). Thus, a cross-species moiety that is not LPS is responsible for polyclonal stimulation by chlamydia. Because these bacteria can exist in latent forms in an animal, and all forms are immunostimulatory, the question of whether these bacteria can alter immune responses if released during other infections or immunizations has been raised.

Animals↗
PubMed1979

Erythromycin and lymecycline treatment in chlamydia-positive and Chlamydia-negative non-gonococcal urethritis--a partner-controlled study.

A group of 213 men with non-gonococcal urethritis and their sexual partners were treated either with erythromycin stearate 500 mgx2 for 15 days or with lymecycline 300 mgx2 for 10 or 20 days. Chlamydia trachomatis was isolated from 40% of the men, from 26% of their female partners and from 56% of the partners of men with chlamydia-positive urethritis. One hundred and eighty-one men were available for evaluation of therapy. There were no significant differences between the treatment schedules. The cure rate was 86-90% in men with chlamydia-positive and 89-100% in men with chlamydia-negative urethritis. Four of the 17 chlamydia-positive females treated with erythromycin and 2 of the 20 chlamydia-positive females treated with lymecycline for 10 days still had chlamydia at re-examination.

Chlamydia Infections↗
PubMed1989

TestPack Chlamydia, a new rapid assay for the direct detection of Chlamydia trachomatis.

TestPack Chlamydia (Abbott Laboratories) is a rapid enzyme immunoassay for the direct antigen detection of Chlamydia trachomatis in endocervical specimens. The assay is self-contained, requires no specialized equipment, and yields results in less than 30 min. The clinical performance of TestPack Chlamydia versus chlamydial cell culture was evaluated with a total of 1,694 paired endocervical specimens. Discordant samples were further investigated by immunofluorescent staining and by Chlamydiazyme immunoassay, with confirmatory procedures. The sensitivity of TestPack Chlamydia with less-than-48-h-old specimens was 76.5%, while culture sensitivity was 86.7%. TestPack Chlamydia specificity was determined to be 99.5%. These results indicate that TestPack Chlamydia is an accurate test for chlamydial infection, with a positive predictive value of 96.2%. This assay is suitable for low-volume chlamydial testing in physician offices, clinics, and smaller laboratories.

Antigens, Bacterial↗
PubMed1992

Establishment of a particle-counting method for purified elementary bodies of chlamydiae and evaluation of sensitivities of the IDEIA Chlamydia kit and DNA probe by using the purified elementary bodies.

To evaluate the sensitivity of commercially available test kits for detection of chlamydiae, we established a method of purifying Chlamydia trachomatis and Chlamydia pneumoniae elementary bodies (EBs). We then subjected the purified EBs, together with the purified EBs of Chlamydia psittaci, to the IDEIA Chlamydia (IDEIA) and DNA probe test kits to determine the EB numbers at the detection limits. The sensitivities of the test kits were thus compared. The results can be summarized as follows. (i) Intact EBs in the purified preparations were present at 100, 96.3, and 97% for the C. psittaci Cal 10, C. trachomatis L2/434/Bu (L2), and C. pneumoniae TW-183 strains, respectively. The preparations of the L2 and TW-183 EBs contained a few EB envelopes, which reacted with antilipopolysaccharide monoclonal antibodies, as did the intact EBs, indicating that elimination of EB envelopes is not required for testing of the IDEIA kit's sensitivity. (ii) We established a method of counting intact EBs and EB envelopes under a scanning electron microscope after sedimentation of EBs on a coverslip by centrifugation. (iii) The EB numbers per assay at the cutoff level, which is set up in the IDEIA kit, were 9.6 x 10(2), 6.5 x 10(3), and 2.5 x 10(4) for the L2, TW-183, and Cal 10 strains, respectively. When the same EB preparations were applied to the DNA probe kit, the EB number at the cutoff level was 7.5 x 10(3) per assay for the L2 strain, but no reaction occurred for the Cal 10 and TW-183 strains at any EB number, indicating that the DNA probe kit is highly specific for C. trachomatis. Although the IDEIA kit designed for detection of C. trachomatis showed a sensitivity superior to that of the DNA probe, the chlamydial species was not determined by the IDEIA kit.

Bacteriological Techniques↗
PubMed1992

Chlamydia keratoconjunctivitis determination of Chlamydia trachomatis specific secretory immunoglobulin A in tears by enzyme immunoassay.

Determination of Chlamydia trachomatis specific antibodies in serum and tears, isolation of C. trachomatis in cell culture and C. trachomatis antigen detection by direct immunofluorescence test were evaluated for the laboratory diagnosis of Chlamydia trachomatis infection in 30 patients with chronic conjunctivitis. C. trachomatis specific secretory immunoglobulin A (s-IgA) was detected in the tears of all 8 patients with a positive result in culture and the direct immunofluorescence test. In 4 additional patients, the s-IgA assay of tears was also positive. A presumptive clinical diagnosis of Chlamydia conjunctivitis was correlated with the presence of s-IgA in tears. S-IgA was not detected in the serum of any of the patients, indicating that s-IgA is locally produced and not transudated from the serum. For the diagnosis of chronic Chlamydia conjunctivitis, we recommend the determination of s-IgA in tears in addition to a test for Chlamydia detection.

Adolescent↗
PubMed1991

Chlamydia trachomatis and Chlamydia pneumoniae bind specifically to phosphatidylethanolamine in HeLa cells and to GalNAc beta 1-4Gal beta 1-4GLC sequences-found in asialo-GM1 and asial-GM2.

To examine the possible role of lipids as adhesion receptors for infection, Chlamydia trachomatis and Chlamydia pneumoniae were labeled with 125I and layered on thin-layer chromatograms (tlc) of separated lipids isolated from target cells, and bound bacteria were detected by autoradiography. Elementary bodies from both species bound specifically and with high affinity to one lipid in HeLa 229 cells. Purification of this receptor by column chromatography on DEAE Sepharose followed by continuous preparative tlc, and structural analysis by 500-MHz 1H-NMR spectroscopy and fast atom bombardment mass spectrometry confirmed the HeLa cell chlamydial receptor to be phosphatidylethanolamine (PE). The chlamydiae also bound strongly to purified asialo-GM1 and asialo-GM2, but not to other neutral or acidic lipids tested. The relative binding of chlamydiae to human PE and asialo-GM1 was modified in the presence divalent cations, suggesting that chlamydiae have two interrelated receptor binding sites.

Bacterial Adhesion↗
PubMed1992

Proposal of Chlamydia pecorum sp. nov. for Chlamydia strains derived from ruminants.

Chlamydia pecorum sp. nov. is proposed as the fourth species of the genus Chlamydia on the basis of the results of a genetic analysis of Chlamydia strains that were isolated from cattle and sheep which had various diseases, including sporadic encephalitis, infectious polyarthritis, pneumonia, and diarrhea. The levels of DNA-DNA homology between C. pecorum and strains of C. psittaci, Chlamydia pneumoniae, and Chlamydia trachomatis were less than 10%. Several DNA probes were used to identify C. pecorum. The C. pecorum strains were distinguished from C. psittaci strains by the results of immunological assays, including an immunofluorescence antibody assay performed with monoclonal antibodies and an immunoblot analysis of the immunological specificity of the major outer membrane protein. Species identification was based on results obtained from DNA analyses and serology. The type strain of C. pecorum is strain ATCC VR628.

Animals↗
PubMed1991

Comparison of the Clearview Chlamydia test, Chlamydiazyme, and cell culture for detection of Chlamydia trachomatis in women with a low prevalence of infection.

Two antigen detection systems, Clearview Chlamydia (Unipath Ltd., Bedford, United Kingdom) and Chlamydiazyme (Abbott Laboratories, North Chicago, Ill.), were compared with culture for the diagnosis of chlamydia infection in women attending gynecological clinics. Chlamydia trachomatis was isolated from 43 (4.5%) of the 965 women tested. In comparison with tissue culture, the Clearview Chlamydia and Chlamydiazyme tests had sensitivities of 79.0 and 74.4%, respectively, and both had a specificity of 99.6%. The results show that the Clearview Chlamydia test is comparable to Chlamydiazyme for the detection of C. trachomatis from endocervical specimens in a population with a low prevalence of infection.

Adolescent↗
PubMed1989

[The usefulness of Chlamydia testpack for the diagnosis of Chlamydia trachomatis infection in genito-urinary tract].

A comparative study between Chlamydia Testpack and Chlamydiazyme for the detection of chlamydial antigen was performed. In 61 cases suspected of being chlamydial infection, Chlamydia Testpack had a specificity of 92% and a sensitivity of 88% when compared with Chlamydiazyme. On the result of study using Chlamydia trachomatis serotype B, the sensitivity of Chlamydia Testpack which had a lower limit of 6 x 10(4)/ml of EB was less than that of Chlamydiazyme which had a lower limit of 0.7 x 10(4). However, the large number of EB presented in almost all positive specimen, indicated that Chlamydia Testpack could be used to screen the clinical materials.

Adolescent↗
PubMed1989

Ultrastructural studies on the intracellular fate of Chlamydia psittaci (strain guinea pig inclusion conjunctivitis) and Chlamydia trachomatis (strain lymphogranuloma venereum 434): modulation of intracellular events and relationship with endocytic mechanism.

Previous observations on the highly infectious LGV strain 434 of Chlamydia trachomatis and the guinea pig inclusion conjunctivitis (GPIC) strain of C. psittaci (which requires centrifugation of inocula with host cell monolayers for maximum infectivity) indicated that infectivity differences were expressed, not at entry, but at an intracellular stage affecting multiplication. Centrifugation increased the potential of internalized chlamydiae to undergo productive infection. Here, analysis of the intracellular fate of chlamydiae by ultrastructural methods indicates that strain GPIC exhibits two patterns of behaviour depending on the mode of inoculation. Strain GPIC showed limited entry, with 47% of intracellular organisms becoming associated with thorotrast-labelled lysosomes, following static incubation with monolayers. In contrast, with centrifugation, entry was not limited and association with lysosomes was reduced to 12%; strain 434 behaved similarly but independently of the mode of inoculation. The different results for strain GPIC correlated with distinct entry mechanisms. Entry during static incubation was unimpaired either by treatment with cytochalasin D or by temperature reduction to 20 degrees C, suggesting that it was pinocytic. Entry during centrifugation was markedly impaired by both treatments, suggesting that it was phagocytic. The data lead to two novel conclusions: first, that chlamydiae can apparently enter cells by both pinocytic and phagocytic mechanisms; second, that the entry mechanism influences intracellular fate. It is suggested that entry mechanism is linked to selection of the vesicle membrane forming around the internalizing chlamydiae. This, in turn, may influence both intracellular translocation and subsequent inhibition or promotion of multiplication of the internalized parasite.

Animals↗
PubMed1978

Parasite-specified phagocytosis of Chlamydia psittaci and Chlamydia trachomatis by L and HeLa cells.

Phagocytosis of the 6BC strain of Chlamydia psittaci and the lymphogranuloma venereum 440L strain of Chlamydia trachomatis by L cells and HeLa 229 cells occurred at rates and to extents that were 10 to 100 times greater than those observed for the phagocytosis of Escherichia coli and polystyrene latex spheres. Both species of Chlamydia were efficiently taken up by host cells of a type they had not previously encountered. Phagocytosis of chlamydiae was brought about by the interaction of parasite surface ligands with elements of the host cell surface. The chlamydial ligands were readily denatured by heat, were masked by antibody, and were resistant to proteases and detergents. The host cell components were reversibly removed by proteases. Chlamydial phagocytosis was inhibited when host cells were incubated for many hours with cycloheximide. It was suggested that the presence on the chlamydial cell surface of ligands with high affinity for normal, ubiquitously occurring structures on the surface of host cells is an evolutionary adaptation to intracellular existence. The term parasite-specified phagocytosis was used to describe the efficient phagocytosis of chlamydiae by nonprofessional phagocytes and to distinguish it from the host-specified immunological and non-immunological phagocytosis carried out by professional phagocytes.

Chlamydia trachomatis↗
PubMed1985

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

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 amino acids stimulated synthesis; chloramphenicol, rifampin, oligomycin, and carbonyl cyanide p-trifluoromethoxyphenylhydrazone (a proton ionophore) inhibited incorporation. Ribonucleoside triphosphates (other than ATP) had little stimulatory effect. The optimum pH for host-free synthesis was between 7.0 and 7.5. The molecular weights of proteins synthesized by host-free reticulate bodies closely resembled the molecular weights of proteins synthesized by reticulate bodies in an intracellular environment, and included outer membrane proteins. Elementary bodies of chlamydiae were unable to synthesize protein even when incubated in the presence of 10 mM dithiothreitol, a reducing agent which converted the highly disulfide bond cross-linked major outer membrane protein to monomeric form.

Bacterial Outer Membrane Proteins↗