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
Flocked Fiber Swabs
Puritan® Patented HydraFlock®
New
Gold Member
Nucleic Acid Extractor System
NEOS-96 XT
New
Prefilled Tubes
Prefilled 5.0ml Tubes
New
Electrolyte Analyzer
BKE-B
Latest Immunology News
- Study Finds Influenza Often Undiagnosed in Winter Deaths
- Combined Screening Approach Identifies Early Leprosy Cases
- Antibody Blood Test Identifies Active TB and Distinguishes Latent Infection
- FDA Approval Expands Use of PD-L1 Companion Diagnostic in Esophageal and GEJ Carcinomas
- Study Identifies Inflammatory Pathway Driving Immunotherapy Resistance in Bladder Cancer
- Microfluidic Chip Detects Cancer Recurrence from Immune Response Signals
- Cancer Mutation ‘Fingerprints’ to Improve Prediction of Immunotherapy Response
- Immune Signature Identified in Treatment-Resistant Myasthenia Gravis
- New Biomarker Predicts Chemotherapy Response in Triple-Negative Breast Cancer
- Blood Test Identifies Lung Cancer Patients Who Can Benefit from Immunotherapy Drug
- Whole-Genome Sequencing Approach Identifies Cancer Patients Benefitting From PARP-Inhibitor Treatment
- Ultrasensitive Liquid Biopsy Demonstrates Efficacy in Predicting Immunotherapy Response
- Blood Test Could Identify Colon Cancer Patients to Benefit from NSAIDs
- Blood Test Could Detect Adverse Immunotherapy Effects
- Routine Blood Test Can Predict Who Benefits Most from CAR T-Cell Therapy
- New Test Distinguishes Vaccine-Induced False Positives from Active HIV Infection
Channels
Clinical Chemistry
view channel
Blood Test Predicts Alzheimer Disease Risk Before Imaging Changes and Symptoms
Alzheimer's disease often advances silently for years, making timely risk stratification difficult in routine practice. Current approaches to detect pathology can involve lumbar puncture or positron emission... Read more
Study Finds ApoB Testing More Effective Than LDL for Guiding Lipid Therapy
Routine blood tests that measure low-density lipoprotein (LDL), commonly known as “bad” cholesterol, are widely used to guide lipid-lowering therapy, but they do not always provide a complete picture of... Read more
AI-Enabled POC Test Quantifies Multiple Cardiac Biomarkers
Cardiovascular diseases are a leading cause of death, responsible for nearly 20 million deaths each year. Timely triage of myocardial infarction and heart failure hinges on rapid cardiac biomarker measurement,... Read more
Next Generation Automated Analyzers Increase Throughput for Clinical Chemistry and Electrolyte Testing
Clinical laboratories continue to face staffing shortages, limited space, and growing test volumes that pressure chemistry and electrolyte workflows. Maintaining rapid turnaround times increasingly depends... Read moreMolecular Diagnostics
view channel
Urine-Based Assay Predicts Severe Dengue Risk Early
Dengue is among the most widespread mosquito-borne infections, yet early risk stratification can be difficult when symptoms overlap with other febrile illnesses. Only about 2% to 5% of patients develop... Read more
CE-Marked Blood Test Enables Monitoring of Neuroinflammation in Multiple Sclerosis
Multiple sclerosis affects more than 2.9 million people worldwide and requires ongoing evaluation of disease activity to guide care. Routine monitoring often depends on magnetic resonance imaging (MRI),... Read more
Ultrasensitive Assay Tracks Resistance Mutations MRD Monitoring
Ultrasensitive circulating tumor DNA assessment is being applied to predict and track response to immunotherapy and to detect relapse across multiple solid tumors. Monitoring resistance mutations such... Read more
Extracellular Vesicle RNA Biomarkers Enable Noninvasive IBD Diagnosis and Monitoring
Inflammatory bowel disease (IBD) is a chronic, relapsing gastrointestinal condition whose incidence is rising in industrialized and newly industrialized countries, with prevalence in early‑industrialized... Read moreHematology
view channel
Routine Blood Test Parameters Link Anemia to Cancer Risk and Mortality
Anemia detected in routine care can signal underlying pathology and is frequently encountered in adults. Because it is defined by hemoglobin levels below the normal range, it is often evaluated with red... Read more
Prognostic Tool Guides Personalized Treatment in Rare Blood Cancer
Chronic myelomonocytic leukemia (CMML) is a rare blood cancer in which acquired genetic mutations in bone marrow stem cells drive disease. Stem cell transplantation is the only curative option but carries... Read more
Immunology
view channel
Study Finds Influenza Often Undiagnosed in Winter Deaths
Seasonal influenza drives substantial excess mortality, yet its contribution is often obscured when infections go undiagnosed near the time of death. Many deaths occur outside hospitals or in older adults... Read more
Combined Screening Approach Identifies Early Leprosy Cases
Leprosy remains a significant public health concern, with more than 200,000 new cases reported globally each year and early disease often escaping routine laboratory detection. In its initial phase, bacterial... Read more
Pathology
view channel
Biomarker Predicts Immunotherapy Response and Prognosis in Colorectal Cancer
Colorectal cancer is common and often lethal, and therapeutic decision-making is complicated by heterogeneous tumor microenvironments. Immunotherapy benefits only a small subset of patients, around 5%,... Read more
AI Improves Completeness of Complex Cancer Pathology Reports
Oncology teams increasingly rely on pathology reports that integrate histopathology, immunohistochemistry, and rapidly expanding biomarker testing. As patients live longer and undergo repeated analyses... Read more
AI Tool Predicts Chemotherapy Response in Small Cell Lung Cancer
Small cell lung cancer often presents at an extensive stage and progresses rapidly, leaving little time to tailor first-line therapy. Clinicians currently lack biomarkers to guide which patients will benefit... Read more_image.png "Image: Through neoadjuvant therapy combining chemotherapy with immune checkpoint inhibitors (ICI) for 46 LAGC patients and single-cell transcriptome sequencing, researchers found that tumor cells in the treatment-sensitive group specifically upregulated MHC-II (tumor-specific major histocompatibility complex class II, tsMHC-II) molecules (photo courtesy of Science China Press)")
Tumor-Specific Biomarker Predicts Neoadjuvant Immunotherapy Response in Gastric Cancer
Gastric cancer is the fifth most common malignancy and the fourth leading cause of cancer mortality worldwide, with China bearing nearly half of the global burden. Only a subset of patients benefit from... Read moreTechnology
view channel
Integrated System Streamlines Pre-Analytical Workflow for Molecular Testing
Pre-analytical variation remains a leading source of inconsistent molecular test results and added costs, particularly when laboratories rely on multiple instruments and protocols. Standardizing nucleic... Read more
Noninvasive Sputum Test Detects Early Lung Cancer
Early detection remains critical for improving outcomes in lung cancer, yet clinicians increasingly encounter indeterminate pulmonary nodules found incidentally or through screening, complicating decision-making.... Read more
New AI Tool Enables Rapid Treatment Selection in Pediatric Leukemia
Children with T-cell acute lymphoblastic leukemia face an aggressive disease that remains difficult to treat. Although remission rates have improved, many survivors experience long-term effects from intensive... Read more
Breakthrough Mass Spectrometry Design Could Enable Ultra-Low Abundance Detection
Mass spectrometry is central to identifying and quantifying molecules in complex biological samples, but conventional instruments typically analyze ions sequentially, which can limit detection of rare species.... Read moreIndustry
view channel
Beckman Coulter Gains CE Mark for Rapid Assay Distinguishing Bacterial vs Viral Infections
Clinicians often struggle to distinguish bacterial from viral infections at first presentation because symptoms overlap and definitive culture or molecular results can take hours or days.... Read more
