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
Gold Member
Neonatal Heel Incision Device
Tenderfoot
Automated Clinical Chemistry Analyzer
Envoy 500+
Pipette Calibration System
Artel PCS®
Latest Immunology News
- 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
- Immune Enzyme Linked to Treatment-Resistant Inflammatory Bowel Disease
- Simple Blood Test Could Replace Biopsies for Lung Transplant Rejection Monitoring
- Routine TB Screening Test May Reveal Immune Aging and Mortality Risk
- Biomarkers and Molecular Testing Advance Precision Allergy Care
- Point-of-Care Tests Could Expand Access to Mpox Diagnosis
- T-Cell Senescence Profiling May Predict CAR T Responses
- Finger-Prick Lateral Flow Test Detects Sepsis Biomarkers at Point of Care
- Study Highlights Low Sensitivity of Current Lyme Tests in Early Infection
- Immune Aging Clock Quantifies Immunosenescence and Identifies Therapeutic Target
- Study Finds Influenza Often Undiagnosed in Winter Deaths
Channels
Clinical Chemistry
view channel
Blood Protein Signature Diagnoses Pediatric IBD and Distinguishes Subtypes
Confirming pediatric inflammatory bowel disease (IBD) often requires imaging, endoscopy, and histopathology, prolonging time to diagnosis. Reliable, noninvasive blood tests remain an unmet need in routine... Read more
Blood Test Detects More High-Risk Prostate Cancers Than PSA
Prostate cancer is one of the most common malignancies in men, and screening often struggles to distinguish indolent tumors from clinically significant disease. Prostate-specific antigen (PSA) testing... Read more
Molecular Diagnostics
view channel
Female-Specific RNA Biomarker May Help Explain Sex Differences in Immune Disease
Women show distinct susceptibility to infectious diseases and higher rates of autoimmune disorders, yet the molecular drivers remain unclear. This gap has limited sex-specific diagnostic and prognostic tools.... Read more
Genetic Marker Supports Anti-TNF Therapy Selection in Crohn’s Disease
Crohn’s disease, a major form of inflammatory bowel disease, is increasing across age groups and regions. Responses to current therapies vary widely, with only about half of patients benefiting, underscoring... Read more
Hematology
view channel
Next-Generation Hematology Platform Streamlines High-Complexity Lab Workflows
Sysmex America (Chicago, IL, USA) has introduced the next generation XR-Series, centered on the XR-10 Automated Hematology Module for high-complexity laboratories. The platform builds on the widely used... Read more
Blood Eosinophil Count May Predict Cancer Immunotherapy Response and Toxicity
Immune checkpoint inhibitors have improved outcomes across many cancers, yet only a subset of patients derive durable benefit and biomarkers to guide treatment remain limited. Eosinophils, best known for... Read more
Immunology
view channel
Lung Immune Profiling Reveals Distinct Severe Pneumonia Subtypes
Severe pneumonia often progresses to respiratory failure requiring intensive care and mechanical ventilation. Despite similar clinical presentations, outcomes vary widely, complicating decisions on an... Read more
Lab-on-a-Chip Approach Advances Immune–Cancer Cell Interaction Analysis
Conventional cytotoxicity assays often average responses across thousands of cells, obscuring how individual immune cells engage and kill tumor cells. For immunotherapy evaluation, the precise sequence... Read more
Pathology
view channel
Uncertainty-Aware AI Tool Improves Digital Pathology for Cancer Subtyping
Reliable histologic subtyping guides therapy selection in oncology, yet diagnostic workflows grow more complex as whole-slide imaging and artificial intelligence (AI) expand. A persistent obstacle to clinical... Read more
Study Highlights Biomarker Testing Delays in Lung Cancer Care
Timely biomarker results are critical to match lung cancer patients with targeted therapies or immunotherapies, yet many clinical pathways still delay testing after biopsy. Ordering responsibility, reimbursement... Read more
Technology
view channel
AI Platform Links Biomarker Results to Cancer Clinical Trials and Guidelines
Oncology teams must manage growing volumes of genomic data, rapidly evolving clinical trial options, and frequently updated care guidelines, all within tight clinic schedules. Translating complex tumor... Read more
Agentic AI Platform Supports Genomic Decision-Making in Oncology
Oncology care teams increasingly face the challenge of managing complex molecular diagnostics, evolving treatment options, and extensive electronic health record documentation. Translating multimodal data... Read more
Industry
view channel
Agreement Supports pTau217-Based Alzheimer’s Blood Test Development
As disease-modifying therapies for Alzheimer’s disease expand, accessible diagnostics are increasingly needed to identify patients earlier. Current confirmatory methods, including PET imaging and cerebrospinal... Read more
