We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress hp
Sign In
Advertise with Us
ZeptoMetrix an Antylia scientific company

Download Mobile App




MCDA-LFB Assay Developed for Rapid Detection of Legionnaires’ Disease

By LabMedica International staff writers
Posted on 18 Jan 2022
Print article
Image: Optimized reaction time for Multiple Cross Displacement Amplification (MCDA-LFB) assay to detect Legionella pneumophila. The best sensitivity was seen when the amplification lasted for 35 minutes (Photo courtesy of Zhejiang Provincial People’s Hospital)
Image: Optimized reaction time for Multiple Cross Displacement Amplification (MCDA-LFB) assay to detect Legionella pneumophila. The best sensitivity was seen when the amplification lasted for 35 minutes (Photo courtesy of Zhejiang Provincial People’s Hospital)
Legionella pneumophila is an opportunistic waterborne pathogen of significant public health problems, which can cause serious human respiratory diseases (Legionnaires’ disease). Legionnaires’ disease is characterized by severe lung infection symptoms, including severe pneumonia with a high fatality rate.

Diagnostic methods, including traditional bacterial culture methods, serological testing, urine antigen detection and nucleic acid amplification techniques, have been developed and used to detect Legionnaires’ disease. Multiple cross displacement amplification (MCDA), a novel isothermal nucleic acid amplification technique, has been applied in detecting many bacterial agents.

Respiratory Medicine Specialists at the Zhejiang Provincial People’s Hospital (Hangzhou; People’s Republic of China) developed a MCDA coupled with Nanoparticles-based Lateral Flow Biosensor (MCDA-LFB) for the rapid detection of L. pneumophila. A total of 40 bacterial strains were used in this assay, including 24 strains of L. pneumophila and 16 strains of non-L. pneumophila. The team used traditional bacterial culture method, conventional PCR detection and MCDA-LFB method to test 88 specimens suspected of L. pneumophila. A set of 10 primers based on the L. pneumophila specific mip gene to specifically identify 10 different target sequence regions of L. pneumophila was designed.

The optimal time and temperature for amplification are 57 minutes and 65 °C. The limit of detection (LoD) is 10 fg in pure cultures of L. pneumophila. No cross-reaction was obtained and the specificity of MCDA-LFB assay was 100%. The whole process of the assay, including 20 minutes of DNA preparation, 35 minutes of L. pneumophila-MCDA reaction, and 2 minutes of sensor strip reaction, took a less than 1 hour. Among 88 specimens for clinical evaluation, five (5.68%) samples were L. pneumophila-positive by MCDA-LFB and traditional culture method, while four (4.55%) samples were L. pneumophila-positive by PCR method targeting mip gene. Compared with culture method, the diagnostic accuracy of MCDA-LFB method was higher.

The authors concluded that the L. pneumophila-MCDA-LFB method they successfully developed is a simple, fast, reliable, and sensitive diagnostic tool, which can be widely used for the identification of L. pneumophila in basic and clinical laboratories. The study was published on January 8, 2022 in the journal BMC Microbiology.

Related Links:
Zhejiang Provincial People’s Hospital

Gold Member
Veterinary Hematology Analyzer
Exigo H400
Verification Panels for Assay Development & QC
Seroconversion Panels
New
Pipet Controller
Stripettor Pro
New
Calprotectin Assay
Fecal Calprotectin ELISA

Print article

Channels

Clinical Chemistry

view channel
Image: QIP-MS could predict and detect myeloma relapse earlier compared to currently used techniques (Photo courtesy of Adobe Stock)

Mass Spectrometry-Based Monitoring Technique to Predict and Identify Early Myeloma Relapse

Myeloma, a type of cancer that affects the bone marrow, is currently incurable, though many patients can live for over 10 years after diagnosis. However, around 1 in 5 individuals with myeloma have a high-risk... Read more

Immunology

view channel
Image: The cancer stem cell test can accurately choose more effective treatments (Photo courtesy of University of Cincinnati)

Stem Cell Test Predicts Treatment Outcome for Patients with Platinum-Resistant Ovarian Cancer

Epithelial ovarian cancer frequently responds to chemotherapy initially, but eventually, the tumor develops resistance to the therapy, leading to regrowth. This resistance is partially due to the activation... Read more

Technology

view channel
Image: The HIV-1 self-testing chip will be capable of selectively detecting HIV in whole blood samples (Photo courtesy of Shutterstock)

Disposable Microchip Technology Could Selectively Detect HIV in Whole Blood Samples

As of the end of 2023, approximately 40 million people globally were living with HIV, and around 630,000 individuals died from AIDS-related illnesses that same year. Despite a substantial decline in deaths... Read more

Industry

view channel
Image: The collaboration aims to leverage Oxford Nanopore\'s sequencing platform and Cepheid\'s GeneXpert system to advance the field of sequencing for infectious diseases (Photo courtesy of Cepheid)

Cepheid and Oxford Nanopore Technologies Partner on Advancing Automated Sequencing-Based Solutions

Cepheid (Sunnyvale, CA, USA), a leading molecular diagnostics company, and Oxford Nanopore Technologies (Oxford, UK), the company behind a new generation of sequencing-based molecular analysis technologies,... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.