LabMedica

Download Mobile App
Recent News Expo Clinical Chem. Molecular Diagnostics Hematology Immunology Microbiology Pathology Technology Industry Focus

Optimized Immunoassays Detect HBV in Oral Fluid Samples

By LabMedica International staff writers
Posted on 05 Sep 2019
Image: A collection of whole saliva by the Salivette (absorbent) method. (a) Saliva is collected by chewing a cotton wool swab. (b) The swab containing saliva is placed in the tube of Salivette. (c) Centrifugation of the assemblage. (d) Saliva is separated from the swab and is ready for analysis (Photo courtesy of Sarstedt).
Image: A collection of whole saliva by the Salivette (absorbent) method. (a) Saliva is collected by chewing a cotton wool swab. (b) The swab containing saliva is placed in the tube of Salivette. (c) Centrifugation of the assemblage. (d) Saliva is separated from the swab and is ready for analysis (Photo courtesy of Sarstedt).
It is estimated that there are 257 million chronic hepatitis B (HBV) carriers worldwide, which highlights the substantial health, social, and economic burden of HBV. Screening of infected, cured and vaccinated individuals is necessary to identify the presence of chronically infected reservoirs, immune and susceptible individuals.

Currently, HBV infection diagnosis is performed using serum and plasma samples collected via venipuncture, which can be invasive, expensive, and potentially painful and arduous for some individuals including the elderly, obese, patients receiving hemodialysis, and drug users. In regions where financial resources are scarce, it would be beneficial to use methods with low cost and biological risk, such as oral fluid samples.

Scientists at the Oswaldo Cruz Institute (Rio de Janeiro, Brazil) optimized a commercially available assay for detecting total anti-HBc marker in oral fluid samples and evaluated its utility under real life conditions in different settings for the purposes of prevalence and diagnostic studies. The team collected blood samples, which were centrifuged for serum. Oral fluid was obtained using a commercial Salivette device. All serum samples were submitted to commercial Enzyme immunoassays (EIAs) to detect total anti-HBc antibodies directed against HBV surface antigen (anti-HBs) and HBsAg. All oral fluid samples were also tested with the Diasorin EIA ETI-AB-COREK-PLUS, designed to detect total anti-HBc in serum.

Optimization found the best elution buffer was PBS/BSA 0.5% and the best oral fluid sample volume was 100 µL. The team used these optimized parameters, 1,085 of the samples collected from the 1,296 participants did not detect anti-Hbc; in 211 samples, anti-HBc was detected. The oral fluid sensitivity was 52.6% and specificity was 96%. Sensitivity was higher in patients presenting with an active HBV infection compared with anti-HBc isolate and past infection, 92.7%, 43.2%, and 36.9%, respectively. In addition, sensitivity was higher in participants without active hepatitis C virus infection and also in participants who used injection drugs (85.9%).

The authors concluded that it was possible to optimize a commercial enzyme-linked immunosorbent assay for detecting anti-HBc in oral fluid samples where the highest concordance was found in ambulatory settings and among individuals with active infection. The study was published on July 17, 2019, in the journal BMC Infectious Diseases.

Related Links:
Oswaldo Cruz Institute

Platinum Member
Automated Coagulation Analyzer
Hemolumi H6
βeta-Hydroxybutyrate Reagent
β-Hydroxybutyrate LiquiColor®
Gold Member
Blood-Based Protein Biomarker Solution for Alzheimer's Disease
BG-DTi2000.
New
Gold Member
Serum Indices Control
Acusera Serum Indices Control

Channels

Molecular Diagnostics

view channel
Image: The test combines RNA signals from the tumor-immune microenvironment to predict treatment response, rather than relying on a single marker such as PD-L1 expression.(Image Credit: Adobe Stock)

RNA-Based Test Predicts Immunotherapy Response in Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) represents the largest U.S. patient population eligible for immune checkpoint inhibitor therapy. Treatment selection often relies on PD-L1 expression, but a single protein... Read more

Immunology

view channel
Image Credit: Adobe Stock

Immune Profiling Identifies Early Maternal Autoantibodies Linked to Preterm Birth Risk

A typical pregnancy lasts about 40 weeks, but labor begins prematurely in roughly one in 10 pregnancies. Preterm birth is the leading cause of newborn death worldwide, yet its underlying causes and which... Read more

Technology

view channel
Image: The laser-based photoacoustic spectroscopy setup consists of a Mid-IR laser equipped with three QCL modules covering wavelengths from 5.6 μm to 12.9 μm, two silver coated mirrors (SCM), a dichroic mirror (DM) with a transmittance of 90%, a thermal power sensor head (PM) to monitor the output laser power, a mechanical chopper (MC) for frequency modulation and a CEPAS-detector with a self-designed swab holder (SH). (Credit: Graunke, T., Scholz, T., Pieniak, M. et al. Scientific Reports (2026). https://doi.org/10.1038/s41598-026-68298-9)

Laser-Based Swab Analysis Shows Promise for Detecting Disease-Linked Odor Patterns

Disease-related changes in volatile organic compounds can alter body odor, producing measurable patterns in exhaled breath and bodily fluids. Current analytical methods can be complex, time-consuming,... Read more

Industry

view channel
Image Credit: iStock

Global TB Summit Connects Diagnostic Testing With Prevention and Clinical Care

Tuberculosis remains a major global infectious disease challenge despite declining deaths. In 2024, an estimated 10.7 million people worldwide developed the disease and nearly 1.2 million died from it.... Read more