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
Sign In
Advertise with Us
Abbott Diagnostics- Hematology Division


Biosynex designs, manufactures and distributes Rapid Diagnostic Tests (RDTs) which, in their professional version, al... read more Featured Products: More products

Download Mobile App


ATTENTION: Due to the COVID-19 PANDEMIC, many events are being rescheduled for a later date, converted into virtual venues, or altogether cancelled. Please check with the event organizer or website prior to planning for any forthcoming event.
21 Jun 2021 - 24 Jun 2021

LAMP Assay Developed to Diagnose High HBV DNA Levels

By LabMedica International staff writers
Posted on 05 May 2021
Print article
Image: The AMPLIX real-time polymerase chain reaction system (Photo courtesy of Biosynex)
Image: The AMPLIX real-time polymerase chain reaction system (Photo courtesy of Biosynex)
Worldwide, 257 million people are chronically infected with hepatitis B virus (HBV) and 887,000 annually die from cirrhosis or liver cancer. Since more than 95% of HBV-infected people live in low-income and middle-income countries (LMICs) and only 12-25% of infected people are eligible for anti-HBV therapy.

Loop-mediated isothermal amplification (LAMP) assay is a nucleic acid test (NAT) using DNA polymerase with high auto-cycling strand displacement activity and six specially designed primers. LAMP has the following characteristics allowing its use as a rapid, reliable and inexpensive point-of-care test in LMICs with a high amplification efficiency enabling rapid detection of nucleic acids.

A large team of medical scientists associated with the Pasteur Institute (Paris, France) designed Pan-genotypic primer sets on conserved HBV gene regions. Accuracy of LAMP to identify highly viremic patients was evaluated in 400 and 550 HBV-infected people in France and Senegal, respectively. Analytical validation was performed using real-time turbidimetric LAMP (Loopamp LA-500, Eiken Chemical, Japan). Viral loads were quantified using an AMPLIX real-time PCR (Biosynex, Illkirch-Graffenstaden France).

The team reported that their primers successfully detected eight major HBV genotypes/sub-genotypes (A1/2/3/B/C/D/E/F) with a detection limit ranging between 40-400 IU/mL. In France, the area under the receiver operating characteristic curve (AUROC), sensitivity and specificity of bead-based extraction and real-time turbidimetric LAMP were 0.95, 91.1% and 86.0%, respectively, to diagnose HBV DNA ≥20,000 IU/mL; and 0.98, 98.0% and 94.6% for ≥200,000 IU/mL. The performance did not vary by viral genotypes. In Senegal, using a field-adapted method, reagent-free boil-and-spin extraction and inexpensive end-point fluorescence detection, the AUROC, sensitivity and specificity were 0.95, 98.7% and 91.5%, respectively, to diagnose HBV DNA ≥200,000 IU/mL. The assay was not adapted to discriminate low-level viremia.

The authors concluded that they had developed a simple, rapid (60 minutes), and inexpensive (USD 8/assay) alternative to PCR to diagnose high viremia ≥200,000 IU/mL. HBV-LAMP may contribute to eliminating HBV mother-to-child transmission by identifying high-risk pregnant women eligible for antiviral prophylaxis in resource-limited countries. The study was published on April 7, 2021 in the journal Clinical Microbiology and Infection.

Related Links:
Pasteur Institute
Eiken Chemical

Gold Supplier
SARS-CoV-2 Antibody Test
Gold Supplier
Disposable Virus Sampling Tube
Disposable Virus Sampling Tube
Next-Generation Sequencing (NGS) Workstation

Print article
BIOHIT  Healthcare OY


Clinical Chem.

view channel
Image: Blood test for  plasma aldosterone concentration was used to screen For hyperaldosteronism in hypertensive men (Photo courtesy of  VisitHealth Ltd)

Urinary Sodium/Potassium Ratio Screens for Hyperaldosteronism in Hypertensive Men

Among individuals with hypertension, the prevalence of secondary hypertension has been reported to be around 10%. More than half of individuals with secondary hypertension have associated hyperaldosteronism.... Read more


view channel

Global Clinical Chemistry Analyzers Market to Reach USD 15.97 Billion by 2028

The global clinical chemistry analyzers market is projected to grow at a CAGR of 4.25% from USD 11.45 billion in 2020 to USD 15.97 billion by 2028, driven by growth in technology, rising global population,... Read more
Copyright © 2000-2021 Globetech Media. All rights reserved.