Development of a duplex real-time TaqMan PCR assay with an internal control for the detection ofMycoplasma gallisepticumandMycoplasma synoviaein clinical samples from commercial and backyard poultry

AbstractHuman leukocyte antigen B27 (HLA-B27) is strongly associated with ankylosing spondylitis. The B27 allele is present in 90% of patients with this disease, whereas it is present in only 9% of Caucasians. Molecular detection of HLA-B27 is traditionally based on allele specific amplification of exon 2 (Olerup method) or exon 3 (Dominguez method) by PCR, followed by gel analysis.We developed a real-time TaqMan PCR based on the Dominguez method with a β-Globin PCR as internal control.A total of 544 clinical samples were used to compare the real-time TaqMan PCR with the traditional Dominguez PCR, the traditional Olerup PCR and a commercial Olerup based HLA-B27 detection kit (With a correct result for 543 out of 544 samples (99.8%), we consider our real-time HLA-B27 PCR is a reliable method to detect HLA-B27 in the Dutch population, with reduced hands-on time and contamination risk compared to traditional PCR methods.

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Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its first variants in fourplex real-time quantitative reverse transcription-PCR assays

Microbial Cell ◽

10.15698/mic2022.01.767 ◽

2022 ◽

Vol 9 (1) ◽

pp. 1-20

Author(s):

Mathieu Durand ◽

Philippe Thibault ◽

Simon Lévesque ◽

Ariane Brault ◽

Alex Carignan ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Real Time ◽

Internal Control ◽

Reverse Transcription ◽

Locked Nucleic Acid ◽

Clinical Samples ◽

Quantitative Detection ◽

Respiratory Pathogens ◽

Pcr Assay ◽

Reverse Transcription Pcr

The early diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections is required to identify and isolate contagious patients to prevent further transmission of SARS-CoV-2. In this study, we present a multitarget real-time TaqMan reverse transcription PCR (rRT-PCR) assay for the quantitative detection of SARS-CoV-2 and some of its circulating variants harboring mutations that give the virus a selective advantage. Seven different primer-probe sets that included probes containing locked nucleic acid (LNA) nucleotides were designed to amplify specific wild-type and mutant sequences in Orf1ab, Envelope (E), Spike (S), and Nucleocapsid (N) genes. Furthermore, a newly developed primer-probe set targeted human β2-microglobulin (B2M) as a highly sensitive internal control for RT efficacy. All singleplex and fourplex assays detected £ 14 copies/reaction of quantified synthetic RNA transcripts, with a linear amplification range of nine logarithmic orders. Primer-probe sets for detection of SARS-CoV-2 exhibited no false-positive amplifications with other common respiratory pathogens, including human coronaviruses NL63, 229E, OC43, and HKU-1. Fourplex assays were evaluated using 160 clinical samples positive for SARS-CoV-2. Results showed that SARS-CoV-2 viral RNA was detected in all samples, including viral strains harboring mutations in the Spike coding sequence that became dominant in the pandemic. Given the emergence of SARS-CoV-2 variants and their rapid spread in some populations, fourplex rRT-PCR assay containing four primer-probe sets represents a reliable approach to allow quicker detection of circulating relevant variants in a single reaction.

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Four-color multiplex real-time PCR assay prototype targeting azithromycin resistance mutations in Mycoplasma genitalium

BMC Infectious Diseases ◽

10.1186/s12879-019-4424-2 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 3

Author(s):

Olivier Thellin ◽

Benaïssa Elmoualij ◽

Willy Zorzi ◽

Jorgen S. Jensen ◽

Renaud Close ◽

...

Keyword(s):

Real Time ◽

Internal Control ◽

Plasmid Dna ◽

Limit Of Detection ◽

Analytical Data ◽

Mycoplasma Genitalium ◽

Clinical Samples ◽

Resistance Mutations ◽

Pcr Assay ◽

Azithromycin Resistance

Abstract Background The worldwide expansion of macrolide-resistant Mycoplasma genitalium (MG) in cases of genital infections has led to an increased recurrence rate of these infections after first-line azithromycin treatment. By detecting the presence of azithromycin-resistant MG, the patient’s antibiotic treatment can be targeted and the spread of resistance prevented. With this aim in mind, macrolide-resistance detection kits are helpful tools for the physician. Methods Azithromycin resistance mutations in MG are targeted using a four-color multiplex real-time RT-PCR assay. Tested targets include plasmid DNA (as positive controls) as well as macrolide-sensitive and macrolide-resistant genomic DNA from characterized cell lines and clinical samples. Results The analytical data presented here were generated from plasmid DNA and genomic RNA/DNA and include adaptation to an internal control, specificity between targets, specificity vs non-MG species, limit of detection (LoD) and interference studies (co-infection and endogenous substances). The clinical data were based on the application of the assay to clinical samples characterized by sequencing. Conclusions A new NAAT (nucleic acid amplification test) prototype has been developed in collaboration with the Diagenode s.a. company, this prototype targets MG and azithromycin-resistance mutations in that pathogen.

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Development of Real-Time PCR Based on A137R Gene for the Detection of African Swine Fever Virus

Frontiers in Veterinary Science ◽

10.3389/fvets.2021.753967 ◽

2021 ◽

Vol 8 ◽

Author(s):

Dan Yin ◽

Renhao Geng ◽

Hui Lv ◽

Chunhui Bao ◽

Hongxia Shao ◽

...

Keyword(s):

Real Time ◽

Real Time Pcr ◽

African Swine Fever Virus ◽

African Swine Fever ◽

Fever Virus ◽

Economic Losses ◽

Clinical Samples ◽

Pcr Assay ◽

Taqman Pcr ◽

Control And Eradication

African swine fever virus (ASFV) can infect domestic pigs and wild boars and causes huge economic losses in global swine industry. Therefore, early diagnosis of ASFV is important for the control and eradication of African swine fever (ASF). In this study, a SYBR Green-based real-time polymerase chain reaction (PCR) assay targeting the viral encoded A137R gene was established for the detection of ASFV infection. For the evaluation of the established real-time PCR, 34 clinical samples were assessed by both the A137R gene-based real-time PCR and OIE-recommended TaqMan PCR. The results showed that 85.29% (29/34) were detected by A137R gene-based real-time PCR, but only 79.41% (27/34) positive using OIE-recommended TaqMan PCR. Moreover, no cross-reaction with other common swine pathogens was found in the A137R gene-based real-time PCR. These results demonstrated that the established real-time PCR assay in this study showed better performance than the OIE-recommended method in detecting ASFV from clinical samples, which could be applied for control and eradication programs of ASF.

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Analysis and validation of a highly sensitive one-step nested quantitative real-time polymerase chain reaction assay for specific detection of severe acute respiratory syndrome coronavirus 2

Virology Journal ◽

10.1186/s12985-020-01467-y ◽

2020 ◽

Vol 17 (1) ◽

Author(s):

Yang Zhang ◽

Chunyang Dai ◽

Huiyan Wang ◽

Yong Gao ◽

Tuantuan Li ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Quantitative Polymerase Chain Reaction ◽

Clinical Samples ◽

Chain Reaction ◽

Pcr Assay ◽

Qrt Pcr ◽

Highly Sensitive ◽

One Step ◽

Polymerase Chain

Abstract Background Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is posing a serious threat to global public health. Reverse transcriptase real-time quantitative polymerase chain reaction (qRT-PCR) is widely used as the gold standard for clinical detection of SARS-CoV-2. Due to technical limitations, the reported positive rates of qRT-PCR assay of throat swab samples vary from 30 to 60%. Therefore, the evaluation of alternative strategies to overcome the limitations of qRT-PCR is required. A previous study reported that one-step nested (OSN)-qRT-PCR revealed better suitability for detecting SARS-CoV-2. However, information on the analytical performance of OSN-qRT-PCR is insufficient. Method In this study, we aimed to analyze OSN-qRT-PCR by comparing it with droplet digital PCR (ddPCR) and qRT-PCR by using a dilution series of SARS-CoV-2 pseudoviral RNA and a quality assessment panel. The clinical performance of OSN-qRT-PCR was also validated and compared with ddPCR and qRT-PCR using specimens from COVID-19 patients. Result The limit of detection (copies/ml) of qRT-PCR, ddPCR, and OSN-qRT-PCR were 520.1 (95% CI: 363.23–1145.69) for ORF1ab and 528.1 (95% CI: 347.7–1248.7) for N, 401.8 (95% CI: 284.8–938.3) for ORF1ab and 336.8 (95% CI: 244.6–792.5) for N, and 194.74 (95% CI: 139.7–430.9) for ORF1ab and 189.1 (95% CI: 130.9–433.9) for N, respectively. Of the 34 clinical samples from COVID-19 patients, the positive rates of OSN-qRT-PCR, ddPCR, and qRT-PCR were 82.35% (28/34), 67.65% (23/34), and 58.82% (20/34), respectively. Conclusion In conclusion, the highly sensitive and specific OSN-qRT-PCR assay is superior to ddPCR and qRT-PCR assays, showing great potential as a technique for detection of SARS-CoV-2 in patients with low viral loads.

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Performance evaluation of cobas HBV real-time PCR assay on Roche cobas 4800 System in comparison with COBAS AmpliPrep/COBAS TaqMan HBV Test

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2017-1133 ◽

2018 ◽

Vol 56 (7) ◽

pp. 1133-1139 ◽

Cited By ~ 7

Author(s):

Hanah Kim ◽

Mina Hur ◽

Eunsin Bae ◽

Kyung-A Lee ◽

Woo-In Lee

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Limit Of Detection ◽

Nucleic Acid Amplification ◽

Coefficient Of Determination ◽

Clinical Samples ◽

Pcr Assay ◽

Cobas Taqman ◽

Limit Of Quantitation ◽

Two Systems

Abstract Background: Hepatitis B virus (HBV) nucleic acid amplification testing (NAAT) is important for the diagnosis and management of HBV infection. We evaluated the analytical performance of the cobas HBV NAAT (Roche Diagnostics GmbH, Mannheim, Germany) on the cobas 4800 System in comparison with COBAS AmpliPrep/COBAS TaqMan HBV Test (CAP/CTM HBV). Methods: Precision was evaluated using three levels of cobas HBV/HCV/HIV-1 Control Kit, and linearity was evaluated across the anticipated measuring range (10.0–1.0×109 IU/mL) at seven levels using clinical samples. Detection capability, including limit of blank (LOB), limit of detection (LOD) and limit of quantitation (LOQ), was verified using the 4th WHO International Standard for HBV DNA for NAT (NIBSC code: 10/266). Correlation between the two systems was compared using 205 clinical samples (102 sera and 103 EDTA plasma). Results: Repeatability and total imprecision (coefficient of variation) ranged from 0.5% to 3.8% and from 0.5% to 3.5%, respectively. Linearity (coefficient of determination, R2) was 0.999. LOB, LOD and LOQ were all acceptable within the observed proportion rate (85%). Correlation was very high between the two systems in both serum and plasma samples (correlation coefficient [r]=0.995). Conclusions: The new cobas HBV real-time PCR assay on the cobas 4800 System showed reliable analytical performances.

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