Development and evaluation of a novel quenching probe PCR (GENECUBE) assay for rapidly detecting and distinguishing between Chlamydia pneumoniae and Chlamydia psittaci

2021 ◽  
Vol 184 ◽  
pp. 106212
Author(s):  
Kyoko Hisada ◽  
Yukio Hida ◽  
Naoki Kawabata ◽  
Yosuke Kawashima ◽  
Yoshihiro Soya ◽  
...  
Keyword(s):  
Chlamydia Pneumoniae ◽  
Chlamydia Psittaci ◽  
Quenching Probe

scholarly journals Methodologies and Cell Lines Used for Antimicrobial Susceptibility Testing of Chlamydia spp

2003 ◽  
Vol 47 (2) ◽  
pp. 636-642 ◽  
Author(s):  
R. J. Suchland ◽  
W. M. Geisler ◽  
Walter E. Stamm
Keyword(s):  
Cell Line ◽  
Chlamydia Pneumoniae ◽  
Susceptibility Testing ◽  
Chlamydia Psittaci ◽  
In Vitro Susceptibility ◽  
Persistent Infections ◽  
In Vitro Susceptibility Testing ◽  
Cell Culture Passage ◽  
Selection Of

ABSTRACT In vitro susceptibility testing was performed on strains of Chlamydia trachomatis, Chlamydia pneumoniae, and Chlamydia psittaci under various conditions, including the cell line utilized, the time between infection and the addition of an antimicrobial, the concentration of inoculum, and the effect of multiple passage on the minimal chlamydicidal concentrations for the antibiotics doxycycline, azithromycin, erythromycin, ofloxacin, and tetracycline. With macrolides, the MIC varied depending upon the cell line utilized. With all antimicrobials, the MIC was related to the time at which the antimicrobial was added after infection. By an optimized cell culture passage method, all strains of chlamydia tested demonstrated survival after exposure to high levels (>100 times the MIC) of antimicrobials. Furthermore, upon retest, these surviving organisms did not demonstrate increased MICs. Thus, this phenomenon does not reflect selection of antimicrobial-resistant mutants but rather survival of some organisms in high antimicrobial concentrations (heterotypic survival). An additional 44 clinical isolates of C. trachomatis from patients with single-incident infections were tested against those from patients with recurrent or persistent infections, and heterotypic survival was seen in all isolates tested; hence, in vitro resistance did not correlate with the patient's apparent clinical outcome.

scholarly journals Touchdown Enzyme Time Release-PCR for Detection and Identification of Chlamydia trachomatis, C. pneumoniae, and C. psittaci Using the 16S and 16S-23S Spacer rRNA Genes

2000 ◽  
Vol 38 (3) ◽  
pp. 1085-1093 ◽  
Author(s):  
Guillermo Madico ◽  
Thomas C. Quinn ◽  
Jens Boman ◽  
Charlotte A. Gaydos
Keyword(s):  
Chlamydia Trachomatis ◽  
Dna Sequences ◽  
Chlamydia Pneumoniae ◽  
Chlamydia Psittaci ◽  
Rrna Genes ◽  
Clinical Samples ◽  
Species Differentiation ◽  
Analytical Sensitivity ◽  
Variable Regions ◽  
Primer Sets

Three touchdown enzyme time release (TETR)-PCR assays were used to amplify different DNA sequences in the variable regions of the 16S and 16S-23S spacer rRNA genes specific for Chlamydia trachomatis, Chlamydia pneumoniae, andChlamydia psittaci as improved tests for sensitive diagnosis and rapid species differentiation. The TETR-PCR protocol used 60 cycles of amplification, which provided improved analytical sensitivity (0.004 to 0.063 inclusion-forming unit ofChlamydia species per PCR). The sensitivity of TETR-PCR with primer set CTR 70-CTR 71 was 96.7%, and the specificity was 99.6%, compared to those of the AMPLICOR PCR for the detection ofC. trachomatis in vaginal swab samples. TETR-PCR forC. pneumoniae with primer set CPN 90-CPN 91 was 90% sensitive and 93.3% specific compared with a nested PCR with primer set CP1/2-CPC/D for clinical respiratory samples. TETR-PCR for C. psittaci with primer set CPS 100-CPS 101 showed substantial agreement with cell culturing (κ, 0.78) for animal tissue samples. Primer sets were then combined into a single multiplex TETR-PCR test. The respective 315-, 195-, and 111-bp DNA target products were precisely amplified when DNA from each of the respectiveChlamydia species or combinations of them was used. Multiplex chlamydia TETR-PCR correctly identified one strain of each of the 15 serovars of C. trachomatis, 22 isolates of C. pneumoniae, and 20 isolates of C. psittaci. The primer sets were specific for each species. No target products were amplified when DNA from C. pecorum or a variety of other microorganisms was tested for specificity. TETR-PCR with primers selected for specific sequences in the 16S and 16S-23S spacer rRNA genes is a valuable test that could be used either with individual primers or in a multiplex assay for the identification and differentiation of Chlamydia species from culture isolates or for the detection of chlamydiae in clinical samples.

scholarly journals Chlamydia Infection in Street Youth: Need for More Aggressive Screening Programs

1996 ◽  
Vol 7 (1) ◽  
pp. 49-52 ◽  
Author(s):  
R Tam ◽  
N MacDonald ◽  
S Feder ◽  
L Giglia ◽  
R Peeling ◽  
...  
Keyword(s):  
Chlamydia Pneumoniae ◽  
Transmitted Disease ◽  
Street Youth ◽  
Chlamydia Psittaci ◽  
Sexual Practices ◽  
Chlamydia Infection ◽  
Consistent Condom ◽  
Screening Programs ◽  
Std Testing ◽  
Std Screening

OBJECTIVES: To determine, first, the sexual practices among street youth in the Ottawa-Carleton, Ontario region; second, the percentage of street youth who report previous sexually transmitted disease (STD) screening; and third, the rate of previous infection withChlamydia trachomatisin this population.METHODS: This prospective street youth pilot study was cross-sectional in design. Street youth aged 15 to 20 years were recruited through a drop-in centre or shelter in Ottawa, Ontario between August and October 1993. Information on demographics, substance use, current sexual practices and STD screening and infection history were obtained through a structured face to face interview and a 75-item questionnaire. PastC trachomatisinfection was determined by microimmunofluorescence assay with purified antigens ofC trachomatis(serovars A to K),Chlamydia psittaci(avian strain 6BC) andChlamydia pneumoniae(TW-183 strain).RESULTS: Ninety-eight per cent of the youth approached participated. Of the 100 street youth (61 males, mean age 17.8 years; 39 females, mean age 17.1 years), 94% were sexually active, with 21% of males and 26% of females having had four or more different sexual partners in the previous year. Only 27% of males and 8% of females reported consistent condom use with all partners all of the time. Thirty per cent of males and 50% of females reported previous STD testing. Of the 100 street youth, 22 (16 males and six females) had had previousC trachomatisinfection by serotesting, but only three of 16 (19%) of these males and three of six (50%) of these females reported previous STD testing. None of the 22 recalled previous diagnosis or treatment for any STD.CONCLUSIONS: These street youth reported a high prevalence of risky sexual behaviour, and this supports the national STD guidelines for targeted screening in this population. The current screening guidelines forC trachomatisin this population do not reach the majority of street youth.

scholarly journals Analysis of the Humoral Immune Response toChlamydia Outer Membrane Protein 2

1998 ◽  
Vol 5 (3) ◽  
pp. 313-318 ◽  
Author(s):  
Per Mygind ◽  
Gunna Christiansen ◽  
Kenneth Persson ◽  
Svend Birkelund
Keyword(s):  
Immune Response ◽  
Membrane Protein ◽  
Outer Membrane ◽  
Outer Membrane Protein ◽  
Humoral Immune Response ◽  
Chlamydia Pneumoniae ◽  
Chlamydia Psittaci ◽  
Enzyme Linked Immunosorbent Assay ◽  
Structural Protein ◽  
Humoral Immune

ABSTRACT The humoral immune response to Chlamydia outer membrane protein 2 (Omp2) was studied. Omp2 is a highly genus-conserved structural protein of all Chlamydia species, containing a variable N-terminal fragment. To analyze where the immunogenic parts were localized, seven highly purified truncated fusion proteins constituting different regions of the protein were produced (Chlamydia pneumoniae-Omp2aa23-aa93,Chlamydia psittaci-Omp2aa23-aa94, andChlamydia trachomatis-Omp2aa23-aa84, aa87-aa547, aa23-aa182, aa167-aa434, aa420-aa547). By an enzyme-linked immunosorbent assay with serologically defined patient sera, Omp2 was found to be a major immunogen of both C. pneumoniae andC. trachomatis infections (P ≪ 0.0001). The humoral immune responses were not confined to any particular region of the Omp2 protein, and no species-specific anti-Omp2 immunoglobulins were detected.

scholarly journals Human Mannose-Binding Protein Inhibits Infection of HeLa Cells by Chlamydia trachomatis

1998 ◽  
Vol 66 (4) ◽  
pp. 1607-1612 ◽  
Author(s):  
Albertina F. Swanson ◽  
R. Alan B. Ezekowitz ◽  
Amy Lee ◽  
Cho-chou Kuo
Keyword(s):  
Chlamydia Trachomatis ◽  
Hela Cells ◽  
Chlamydial Infection ◽  
Chlamydia Pneumoniae ◽  
Binding Protein ◽  
Chlamydia Psittaci ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mannose Binding Protein ◽  
Mannose Binding ◽  
High Mannose

ABSTRACT The role that collectin (mannose-binding protein) may play in the host’s defense against chlamydial infection was investigated. Recombinant human mannose-binding protein was used in the inhibition of cell culture infection by Chlamydia trachomatis(C/TW-3/OT, E/UW-5/Cx, and L2/434/Bu), Chlamydia pneumoniae (AR-39), and Chlamydia psittaci (6BC). Mannose-binding protein (MBP) inhibited infection of all chlamydial strains by at least 50% at 0.098 μg/ml for TW-3 and UW-5, and at 6.25 μg/ml for 434, AR-39, and 6BC. The ability of MBP to inhibit infection with strain L2 was not affected by supplementation with complement or addition of an L2-specific neutralizing monoclonal antibody. Enzyme-linked immunosorbent assay and dot blot analyses showed MBP bound to the surface of the organism to exert inhibition, which appeared to block the attachment of radiolabeled organisms to HeLa cells. Immunoblotting and affinity chromatography indicated that MBP binds to the 40-kDa glycoprotein (the major outer membrane protein) on the outer surface of the chlamydial elementary body. Hapten inhibition assays with monosaccharides and defined oligosaccharides showed that the inhibitory effects of MBP were abrogated by mannose or high-mannose type oligomannose-oligosaccharide. The latter carbohydrate is the ligand of the 40-kDa glycoprotein ofC. trachomatis L2, which is known to mediate attachment, suggesting that the MBP binds to high mannose moieties on the surface of chlamydial organisms. These results suggest that MBP plays a role in first-line host defense against chlamydial infection in humans.

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