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
Latest Immunology News
- Blood Test Detects Organ Rejection in Heart Transplant Patients
- Liquid Biopsy Approach to Transform Diagnosis, Monitoring and Treatment of Lung Cancer
- Computational Tool Exposes Hidden Cancer DNA Changes Influencing Treatment Resistance
- New Tool Detects Breast Cancer Relapses Five Years in Advance
- T Cells in Blood Can Detect Parkinson's Years Before Diagnosis
- POC Diagnostic Platform Performs Immune Analysis Using One Drop of Fingertip Blood
- Treatment Switching Guided by Liquid Biopsy Blood Tests Improves Outcomes for Breast Cancer Patients
- First-Of-Its-Kind Device Profiles Newborns' Immune Function Using Single Blood Drop
- Stem Cell Test Predicts Treatment Outcome for Patients with Platinum-Resistant Ovarian Cancer
- Machine Learning-Enabled Blood Test Predicts Immunotherapy Response in Lymphoma Patients
- Post-Treatment Blood Test Could Inform Future Cancer Therapy Decisions
- Cerebrospinal Fluid Test Predicts Dangerous Side Effect of Cancer Treatment
- New Test Measures Preterm Infant Immunity Using Only Two Drops of Blood
- Simple Blood Test Could Help Choose Better Treatments for Patients with Recurrent Endometrial Cancer
- Novel Analytical Method Tracks Progression of Autoimmune Diseases
Channels
Clinical Chemistry
view channel
New Reference Measurement Procedure Standardizes Nucleic Acid Amplification Test Results
Nucleic acid amplification tests (NAATs) play a key role in diagnosing a wide range of infectious diseases. These tests are generally known for their high sensitivity and specificity, and they can be developed... Read more
Pen-Like Tool Quickly and Non-Invasively Detects Opioids from Skin
Opioid drugs such as fentanyl, morphine, and oxycodone are the primary substances associated with overdose cases in the United States. Standard drug screening procedures typically involve collecting blood,... Read moreMolecular Diagnostics
view channel
Blood Test Could Predict Likelihood of Breast Cancer Spreading to The Bone
When breast cancer spreads to other parts of the body, it becomes secondary or metastatic breast cancer—a stage that, while treatable, is currently incurable. The bone is the most common site for this... Read more
New Infectious Disease Analytics Platform Speeds Up Clinical Decision-Making at POC
During the COVID-19 pandemic, the importance of accurate and timely interpretation of diagnostic data became evident in shaping both public health strategies and clinical outcomes. As the world now grapples... Read moreHematology
view channel
Disposable Cartridge-Based Test Delivers Rapid and Accurate CBC Results
Complete Blood Count (CBC) is one of the most commonly ordered lab tests, crucial for diagnosing diseases, monitoring therapies, and conducting routine health screenings. However, more than 90% of physician... Read more
First Point-of-Care Heparin Monitoring Test Provides Results in Under 15 Minutes
Heparin dosing requires careful management to avoid both bleeding and clotting complications. In high-risk situations like extracorporeal membrane oxygenation (ECMO), mortality rates can reach about 50%,... Read moreImmunology
view channel
Blood Test Detects Organ Rejection in Heart Transplant Patients
Following a heart transplant, patients are required to undergo surgical biopsies so that physicians can assess the possibility of organ rejection. Rejection happens when the recipient’s immune system identifies... Read more
Liquid Biopsy Approach to Transform Diagnosis, Monitoring and Treatment of Lung Cancer
Lung cancer continues to be a major contributor to cancer-related deaths globally, with its biological complexity and diverse regulatory processes making diagnosis and treatment particularly difficult.... Read more
Computational Tool Exposes Hidden Cancer DNA Changes Influencing Treatment Resistance
Structural changes in tumor DNA are among the most damaging genetic alterations in cancer, yet they often go undetected, particularly when tissue samples are degraded or of low quality. These hidden genomic... Read morePathology
view channel
AI Performs Virtual Tissue Staining at Super-Resolution
Conventional histopathology, essential for diagnosing various diseases, typically involves chemically staining tissue samples to reveal cellular structures under a microscope. This process, known as “histochemical... Read more
AI-Driven Preliminary Testing for Pancreatic Cancer Enhances Prognosis
Pancreatic cancer poses a major global health threat due to its high mortality rate, with 467,409 deaths and 510,992 new cases reported worldwide in 2022. Often referred to as the "king" of all cancers,... Read more
Cancer Chip Accurately Predicts Patient-Specific Chemotherapy Response
Esophageal adenocarcinoma (EAC), one of the two primary types of esophageal cancer, ranks as the sixth leading cause of cancer-related deaths worldwide and currently lacks effective targeted therapies.... Read more
Clinical AI Solution for Automatic Breast Cancer Grading Improves Diagnostic Accuracy
Labs that use traditional image analysis methods often suffer from bottlenecks and delays. By digitizing their pathology practices, labs can streamline their work, allowing them to take on larger caseloads... Read moreTechnology
view channel
Inexpensive DNA Coated Electrode Paves Way for Disposable Diagnostics
Many people around the world still lack access to affordable, easy-to-use diagnostics for diseases like cancer, HIV, and influenza. Conventional sensors, while accurate, often rely on expensive equipment... Read more
New Miniature Device to Transform Testing of Blood Cancer Treatments
Chimeric antigen receptor (CAR) T cell therapy has emerged as a groundbreaking treatment for blood cancers like leukemia, offering hope to patients when other treatments fail. However, despite its promise,... Read moreIndustry
view channel
AMP Releases Best Practice Recommendations to Guide Clinical Laboratories Offering HRD Testing
Homologous recombination deficiency (HRD) testing identifies tumors that are unable to effectively repair DNA damage through the homologous recombination repair pathway. This deficiency is often linked... Read more