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
- Antibody Profiling Identifies Preclinical Inflammatory Bowel Disease Years Before Diagnosis
- Ultrasensitive Blood Test Detects Sjögren’s Signature Years Before Diagnosis
- New Assays Expand Cytokine Testing for Transplant and Immunocompromised Patients
- Cell-Free Assay Detects Functional IgE for Food Allergy Diagnosis
- Diagnostic Models Detect Hidden Eye Abnormalities After Mild COVID-19
- Anti-Lipid Antibody Biomarkers May Identify Early Lyme Disease and Persistent Symptoms
- Immune Biomarkers Could Identify Risk of Chronic Critical Illness on ICU Admission
- Emergency Department Opt-Out Testing Program Identifies Undiagnosed HIV
- Airway Immune Signature May Predict Tuberculosis Progression Risk
- New Cellular Biomarkers Correlate with Disease Severity in Sjögren Disease
- Lung Immune Profiling Reveals Distinct Severe Pneumonia Subtypes
- Lab-on-a-Chip Approach Advances Immune–Cancer Cell Interaction Analysis
- Antibody Profiles Provide Clues to Long COVID Severity and Symptoms
- Aptamer-Based Biosensor Enables Mutation-Resilient SARS-CoV-2 Detection
- Metabolic Biomarker Distinguishes Latent from Active Tuberculosis and Tracks Treatment Response
- Study Points to Autoimmune Pathway Behind Long COVID Symptoms
Channels
Clinical Chemistry
view channel
Siemens Adds CE-Marked Capillary Claims for 24 Assays on Atellica Analyzers
Venous blood draws can be challenging in patients with difficult veins, needle phobia, or limited blood volume, and they can slow collection in busy services. Core laboratories also face pressure to expand... Read more
Preoperative Blood Test Predicts Colorectal Cancer Recurrence and Metastasis
Cancer cells require large amounts of nutrients to grow and proliferate, and amino acids support key processes including protein formation, energy production, and DNA synthesis. Colorectal cancer is marked... Read moreMolecular Diagnostics
view channel
Blood Gene Expression Fluctuates More Than Expected Over Time
Blood-based gene expression is widely used to explore disease biology, but temporal variability can complicate interpretation of single time-point measurements. Seasonal shifts, time of day, and subclinical... Read more
Genomic Test Helps Early Breast Cancer Patients Avoid Chemotherapy
Adjuvant chemotherapy decisions in early breast cancer can expose many patients to toxicities without clear benefit when clinical factors alone do not precisely predict recurrence risk. Clinicians therefore... Read more
Residual Disease Test Predicts Merkel Cell Carcinoma Recurrence Earlier Than Antibody Assay
Merkel cell carcinoma is a rare, aggressive skin cancer with a substantial risk of relapse, occurring in about 40% of patients. Surveillance remains challenging because widely used serologic monitoring... Read moreHematology
view channel
Spectral Flow Cytometry Assay Enhances MRD Detection in Multiple Myeloma
imal residual disease (MRD) monitoring is pivotal in multiple myeloma, where persistent malignant plasma cells drive relapse risk and help guide therapy decisions. In the United States, approximately 202,000... Read more
New Marker Helps Detect Aggressive Multiple Myeloma Earlier
Multiple myeloma is an incurable malignancy of plasma cells and the second most common blood cancer worldwide, with more than 188,000 new cases each year. Although therapies have advanced, most patients... Read moreImmunology
view channel
Antibody Profiling Identifies Preclinical Inflammatory Bowel Disease Years Before Diagnosis
Inflammatory bowel disease often develops after a prolonged symptom-free period, complicating timely recognition and clinical intervention. Limited understanding of immune activity during this silent phase... Read more
Ultrasensitive Blood Test Detects Sjögren’s Signature Years Before Diagnosis
Sjögren’s disease is a common autoimmune condition that can be difficult to recognize early, leading to delayed diagnosis and persistent symptom burden. It affects around half a million people in the UK... Read more
New Assays Expand Cytokine Testing for Transplant and Immunocompromised Patients
Eurofins Viracor has introduced three plasma-based assays—CXCL9 (Test Code 33607), CXCL10 (Test Code 33609), and interleukin-18 (IL-18) (Test Code 33611)—expanding its immunology testing menu for transplant... Read morePathology
view channel
AI Digital Pathology Platform Standardizes IHC Scoring in Breast Cancer
Breast cancer diagnostic workflows increasingly depend on accurate quantification of immunohistochemical biomarkers to guide therapy selection, yet manual scoring can be variable and time-consuming.... Read more
Digital Pathology Tool Predicts Breast Cancer Outcomes and Therapy Response
Breast cancer prognosis often depends on microscopic assessment of tumor architecture, a process that can be subjective and lead to variable predictions across patient groups. Quantitative measures that... Read moreTechnology
view channel
Training Device Improves Accuracy of Pooled Molecular Diagnostics
High-throughput molecular diagnostics have transformed infectious disease detection, but many workflows remain difficult to execute accurately without extensive training. Sample pooling can cut per‑test... Read more
New CE-Certified Software Advances Whole-Genome Cancer Testing
European hospitals are increasingly using comprehensive tumor genomics to guide therapy, but routine whole genome sequencing (WGS) requires validated, regulation-compliant workflows. A newly CE-certified... Read more
National Rare Disease Registry Standardizes Genetic and Clinical Data for Coordinated Care
Rare diseases collectively impose a significant clinical burden despite their individual rarity, often involving multisystem presentations and prolonged diagnostic journeys. Limited specialist expertise... Read moreIndustry
view channel
Collaboration Advances Extracellular Vesicle-Based Tests for Neurodegenerative Diseases
NanoSomiX, Inc. and Beckman Coulter Diagnostics announced a collaboration to explore the development of next-generation immunoassays for neurodegenerative diseases using extracellular vesicles (EVs).... Read more




.jpg)



