Recombinant Immunoassay Diagnoses Human Fascioliasis
|
By LabMedica International staff writers Posted on 03 Oct 2013 |
|
Image: Adult of Fasciola hepatica stained with carmine (Photo courtesy of US Centers for Disease Control).
The current diagnosis of human fascioliasis involves the detection of eggs in the stool, however, eggs are not observed during the acute phase when the parasite is migrating through the tissues.
A human immune response to Fasciola antigens occurs early in infection, therefore, an immunological method such as an enzyme-linked immunosorbent assay (ELISA) may be a more reliable, easy and cheap means to diagnose human fascioliasis than coprological analysis.
Scientists from McGill University (Montreal, QC, Canada) collected serum samples from 93 Cuban individuals that were coprologically positive for eggs of F. hepatica and clinically diagnosed in the hospital. Samples were also collected from 72 Cuban and 63 Canadian individuals that were shown to be negative for Fasciola infection, and 158 serum samples obtained from individuals infected with other parasitic diseases. The ELISA test was optimized using a recombinant form of the major F. hepatica cathepsin L1 protease antigen (FhCL1).
The ELISA test using anti-total immunoglobulin G (IgG) secondary antibody gave 99.99% specificity and also exhibited 99.99% sensitivity for identifying infected individuals. The results showed that absorbance readings obtained with sera from patients infected with parasites other than F. hepatica closely matched that obtained with the negative control samples. The investigators found that using 0.55 optical density (OD) units as cut-off with anti-total IgG as secondary antibody, the test can discriminate between F. hepatica patients and all other infections examined.
The authors concluded that their standardized ELISA test using a highly stable recombinant form of cathepsin L1, FhCL1, exhibits high sensitivity and specificity and with no cross-reaction with other parasitic diseases. High production of this enzyme can be obtained by purification of Pichia pastoris culture medium, which provides sufficient quantities of material to supply diagnostic centers for mass screening in regions where human fascioliasis is prevalent. The study was published on September 19, 2013, in the journal Public Library of Science Neglected Tropical Disease.
Related Links:
McGill University
A human immune response to Fasciola antigens occurs early in infection, therefore, an immunological method such as an enzyme-linked immunosorbent assay (ELISA) may be a more reliable, easy and cheap means to diagnose human fascioliasis than coprological analysis.
Scientists from McGill University (Montreal, QC, Canada) collected serum samples from 93 Cuban individuals that were coprologically positive for eggs of F. hepatica and clinically diagnosed in the hospital. Samples were also collected from 72 Cuban and 63 Canadian individuals that were shown to be negative for Fasciola infection, and 158 serum samples obtained from individuals infected with other parasitic diseases. The ELISA test was optimized using a recombinant form of the major F. hepatica cathepsin L1 protease antigen (FhCL1).
The ELISA test using anti-total immunoglobulin G (IgG) secondary antibody gave 99.99% specificity and also exhibited 99.99% sensitivity for identifying infected individuals. The results showed that absorbance readings obtained with sera from patients infected with parasites other than F. hepatica closely matched that obtained with the negative control samples. The investigators found that using 0.55 optical density (OD) units as cut-off with anti-total IgG as secondary antibody, the test can discriminate between F. hepatica patients and all other infections examined.
The authors concluded that their standardized ELISA test using a highly stable recombinant form of cathepsin L1, FhCL1, exhibits high sensitivity and specificity and with no cross-reaction with other parasitic diseases. High production of this enzyme can be obtained by purification of Pichia pastoris culture medium, which provides sufficient quantities of material to supply diagnostic centers for mass screening in regions where human fascioliasis is prevalent. The study was published on September 19, 2013, in the journal Public Library of Science Neglected Tropical Disease.
Related Links:
McGill University
Platinum Member
Automated Coagulation Analyzer
Hemolumi H6
New
Neurofilament Light Chain Assay
Lumipulse G NfL Blood
Gold Member
Electrolyte Analyzer
CBS-4000 (CBS-400)
Latest Immunology News
- Immune Profiling Identifies Early Maternal Autoantibodies Linked to Preterm Birth Risk
- Longitudinal Blood Testing Reveals Changes in Allergen Sensitization During Childhood
- FDA Approval Adds Automated Testing Option for Parvovirus B19 Serology
- Blood-Based Immune Aging Map Could Help Spot Disease Risk Earlier
- Blood-Based Immune Signal Could Reveal Lung Cancer Risk Before Tumors Develop
- Prototype Point-of-Care Test Aims to Improve Neonatal Sepsis Diagnosis
- Single-Tier Lyme Disease Test Shows High Sensitivity in Early Infection
- New Web-Based Platform Helps Autoimmune Laboratories Manage Testing Complexity
- Routine Newborn Blood Spots Can Measure GBS Antibody Levels
- New Autoantibody Test Targets Pre-Symptomatic Type 1 Diabetes Screening
- Blood Test Differentiates Bacterial and Viral Infections in Febrile Infants
- HIV Monitoring Strategy Uses Drug Levels to Guide Resistance Testing
- Werfen Expands Automated APS Testing with FDA-Cleared and CE-Marked IgA Reagent
- Blood Biomarker May Predict Colitis Risk in Checkpoint Inhibitor Therapy
- Blood EBV Activity Biomarkers May Predict Multiple Sclerosis Relapse Months Ahead
- New Cellular Map May Help Predict Crohn’s Disease Course in Children
Channels
Clinical Chemistry
view channel
New One-Step Syphilis Test Could Enable Earlier Detection and Faster Treatment
Syphilis can be difficult to diagnose because its symptoms may resemble other diseases and appear and disappear without treatment. Undetected infection can continue causing harm, spread to partners and... Read more
Multimodal Clinical Data Models Predict Cachexia Risk Across Cancers
Cancer cachexia is a severe wasting syndrome that affects roughly half of patients with cancer and cannot be reversed simply by increasing food intake. It can reduce treatment tolerance, impair quality... Read more
Molecular Diagnostics
view channel
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
Modeling Study Shows Blood-Based CRC Screening Could Prevent More Deaths Than Stool Tests
Colorectal cancer (CRC) screening depends on patient participation and completion of follow-up colonoscopy after an abnormal noninvasive result. Access barriers can make both steps difficult, particularly... Read more
Hematology
view channel
New Myelofibrosis Guidelines Recommend Expanded Genetic Testing at Diagnosis
Myelofibrosis is a rare, life-threatening blood cancer affecting up to six per 100,000 people. The disease causes scarring in the bone marrow, limiting the production of healthy blood cells and potentially... Read more
Handheld Point-of-Care Test Aims to Enable Rapid Coagulation Assessment in Trauma
Severe blood loss and inadequate tissue oxygenation are leading causes of preventable death after traumatic injury. Blood products are essential in trauma care, but cold-chain storage, short shelf life,... Read more
Immunology
view channel
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
Longitudinal Blood Testing Reveals Changes in Allergen Sensitization During Childhood
Food allergy is a major childhood health concern, and distinguishing persistent risk from transient sensitization can guide clinical decisions. Specific IgE antibodies may be detectable even when a child... Read more
Pathology
view channel
Molecular Testing Refines Barrett’s Esophagus Progression Risk Beyond Biopsy Findings
Barrett’s esophagus is a precancerous condition associated with increased risk of esophageal adenocarcinoma. Routine endoscopic biopsy findings guide surveillance and therapy, but histopathology may not... Read more
Updated Digital Pathology Platform Expands AI Integration for Cancer Diagnosis
Digital pathology is reshaping how laboratories manage case review, image analysis, and collaboration. As diagnostic workflows become more complex, pathology teams need platforms that can support digital... Read more
Technology
view channel
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
Laser-Enhanced Assay Boosts Sensitivity for Colorectal Cancer Biomarker Detection
Colorectal cancer is the third most commonly diagnosed cancer and the second leading cause of cancer-related death worldwide. Early detection remains critical, but cancer biomarkers can produce only faint... Read more
Industry
view channel
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
