Preliminary evaluation of the ligase chain reaction for specific detection of Neisseria gonorrhoeae

Abstract

Rapid identification of Neisseria gonorrhoeae in clinical specimens is essential for effective control. Traditional culture requires a minimum of 24 h, and for some specimens harboring gonococci, the gonococci fail to grow or are misidentified. The recently described ligase chain reaction (LCR) is a highly specific and sensitive DNA amplification technique which was evaluated as an alternative to routine culture. Three LCR probe sets were used. Two of the probe sets were directed against the multi-copy Opa genes (Omp-II), while the third set was targeted against the multicopy Pilin genes. Each LCR probe set was evaluated with 260 microorganisms including 136 global isolates of N. gonorrhoeae, 41 isolates of N. meningitidis, and 10 isolates of N. lactamica; 26 nonpathogenic Neisseria strains; and 47 isolates of non-Neisseria species that may reside in clinical specimens. Amplification products were detected by using the IMx LCR format (Abbott Laboratories, Abbott Park, Ill.). Strains of N. gonorrhoeae were assayed at 270 cells per LCR (approximately 6.7 x 1i0 CFU/ml) with the Opa and Puin probes, producing signals at least 21 and 15 times above background, * Corresponding author. MATERIALS AND METHODS Bacterial strains and growth. As shown in Table 1, a total

Molecular genetic methods for diagnosis and characterisation of Chlamydia trachomatis and Neisseria gonorrhoeae: impact on epidemiological surveillance and interventions

“…These identify N. gonorrhoeae‐ specific chromosomal genes encoding outer membrane proteins such as the reduction‐modifiable protein (Rmp) (65), the chromosomal putative cytosine DNA methyltransferase gene (Cobas Amplicor, Roche Diagnostics; 66, 67), the 16S rRNA gene (66), or the cppB gene located in regions of the cryptic plasmid that may also be integrated in the chromosome (68). LCRs for identification of N. gonorrhoeae chromosomal multicopy pilin genes and opa genes, respectively, have also been developed (LCx, Abbott Laboratories (69, 70)) but are not available anymore. Furthermore, a NASBA technique (NucliSens Basic kit, Organon Teknika; 24), and a TMA (APTIMA Combo 2, Gen‐Probe; 71) for amplification of 16S rRNA, as well as a SDA assay for a chromosomal DNA sequence homologous to a site‐specific recombinase gene, i.e.…”

Evaluation of the semiautomated Abbott LCx Mycobacterium tuberculosis assay for direct detection of Mycobacterium tuberculosis in respiratory specimens

“…The LCx M. tuberculosis Assay (Abbott Laboratories, Diagnostic Division, Chicago, Ill.) uses ligase chain reaction (LCR) amplification technology for the direct detection of M. tuberculosis complex in respiratory specimens. The LCR amplification methods have previously been evaluated for their ability to detect other infectious agents (4,8,9,24). The target sequence of the LCx M. tuberculosis Assay is found within the chromosomal gene of M. tuberculosis which encodes for protein antigen b (3).…”

Advances in ligase chain reaction and ligation-based amplifications for genotyping assays: Detection and applications

“…Detection of Neisseria gonorrhoeae [120][121][122][123][124][125]. Traditional detection methods were time consuming with a minimum of 24 h. LCR provided a rapid and effective diagnostic approach which is essential for disease control [120]. LCR has been used for diagnosis of Chlamydia trachomatis infection [123][124][125][126][127] [130].…”

“…It is robust with high capability for high-throughput applications and has been commercialized by Abbott Diagnostics company as Abbott LCx 1 which was FDA approved since 1994 [62,63]. It has been widely applied for detection of various microorganisms such as Mycobacterium tuberculosis, Chlamydia trachomatis and Neisseria gonorrhea [49,[120][121][122][123][124][125][126][127]131]. The main disadvantage for this version is that it is not suitable for multiplexing applications due to false positive results obtained and therefore it was taken off the market in 2002 [63].…”