Highly Sensitive Immunoassay Detects Malarial Histidine-Rich Protein 2
By LabMedica International staff writers Posted on 15 Nov 2018 |
Image: Histidine-Rich Protein 2 (HRP2) recombinant panel for malaria diagnostic tests (Photo courtesy of Microcoat Biotechnologie).
Malaria is a vector-borne disease of major public health relevance worldwide. The detection of submicroscopic infections in low prevalence settings has become an increasingly important challenge for malaria elimination strategies.
The current field rapid diagnostic tests (RDTs) for Plasmodium falciparum malaria are inadequate to detect low-density infections. Therefore, there is a need to develop more sensitive field diagnostic tools. In parallel, a highly sensitive laboratory reference assay will be essential to evaluate new diagnostic tools.
A team of international scientists mainly associated with PATH (Seattle, WA, USA) collected whole blood samples from participants of the study from Karen Village, Myanmar, and Nagongera, Uganda. The presence or absence of P. falciparum Histidine-Rich Protein 2 (HRP2) was determined by the Alere Malaria Ag P.f (HRP2) ELISA. The analytical and clinical performance of the HS ELISA was determined using recombinant P. falciparum HRP2, P. falciparum native culture parasites, and archived highly pedigreed clinical whole blood specimens.
The scientists reported that the HS ELISA has an analytical sensitivity of less than 25 pg/mL and shows strong specificity for P. falciparum HRP2 when tested against P. falciparum native culture strains with pfhrp2 and pfhrp3 gene deletions. Against clinical whole blood specimens with concordant microscopic and polymerase chain reaction (PCR) results, the HS ELISA showed 100% diagnostic sensitivity and 97.9% diagnostic specificity. For P. falciparum positive specimens with HRP2 concentrations below 400 pg/mL, the sensitivity and specificity were 100% and 88.9%, respectively. The overall sensitivity and specificity for all 352 samples were 100% and 97.3%.
The authors concluded that the HS ELISA demonstrated acceptable sensitivity and specificity for detecting P. falciparum HRP2, including recombinant protein, native culture P. falciparum parasites, and clinical whole blood specimens. This new assay will be useful in assessing new diagnostic tools and possibly other malaria intervention trials due to its lower limit of detection of P. falciparum HRP2. The study was published on November 1, 2018, in the Malaria Journal.
Related Links:
PATH
The current field rapid diagnostic tests (RDTs) for Plasmodium falciparum malaria are inadequate to detect low-density infections. Therefore, there is a need to develop more sensitive field diagnostic tools. In parallel, a highly sensitive laboratory reference assay will be essential to evaluate new diagnostic tools.
A team of international scientists mainly associated with PATH (Seattle, WA, USA) collected whole blood samples from participants of the study from Karen Village, Myanmar, and Nagongera, Uganda. The presence or absence of P. falciparum Histidine-Rich Protein 2 (HRP2) was determined by the Alere Malaria Ag P.f (HRP2) ELISA. The analytical and clinical performance of the HS ELISA was determined using recombinant P. falciparum HRP2, P. falciparum native culture parasites, and archived highly pedigreed clinical whole blood specimens.
The scientists reported that the HS ELISA has an analytical sensitivity of less than 25 pg/mL and shows strong specificity for P. falciparum HRP2 when tested against P. falciparum native culture strains with pfhrp2 and pfhrp3 gene deletions. Against clinical whole blood specimens with concordant microscopic and polymerase chain reaction (PCR) results, the HS ELISA showed 100% diagnostic sensitivity and 97.9% diagnostic specificity. For P. falciparum positive specimens with HRP2 concentrations below 400 pg/mL, the sensitivity and specificity were 100% and 88.9%, respectively. The overall sensitivity and specificity for all 352 samples were 100% and 97.3%.
The authors concluded that the HS ELISA demonstrated acceptable sensitivity and specificity for detecting P. falciparum HRP2, including recombinant protein, native culture P. falciparum parasites, and clinical whole blood specimens. This new assay will be useful in assessing new diagnostic tools and possibly other malaria intervention trials due to its lower limit of detection of P. falciparum HRP2. The study was published on November 1, 2018, in the Malaria Journal.
Related Links:
PATH
Latest Microbiology News
- Integrated Solution Ushers New Era of Automated Tuberculosis Testing
- Automated Sepsis Test System Enables Rapid Diagnosis for Patients with Severe Bloodstream Infections
- Enhanced Rapid Syndromic Molecular Diagnostic Solution Detects Broad Range of Infectious Diseases
- Clinical Decision Support Software a Game-Changer in Antimicrobial Resistance Battle
- New CE-Marked Hepatitis Assays to Help Diagnose Infections Earlier
- 1 Hour, Direct-From-Blood Multiplex PCR Test Identifies 95% of Sepsis-Causing Pathogens
- Mouth Bacteria Test Could Predict Colon Cancer Progression
- Unique Metabolic Signature Could Enable Sepsis Diagnosis within One Hour of Blood Collection
- Groundbreaking Diagnostic Platform Provides AST Results With Unprecedented Speed
- Simple Blood Test Combined With Personalized Risk Model Improves Sepsis Diagnosis
- Blood Analysis Predicts Sepsis and Organ Failure in Children
- TB Blood Test Could Detect Millions of Silent Spreaders
- New Blood Test Cuts Diagnosis Time for Nontuberculous Mycobacteria Infections from Months to Hours
- New Tuberculosis Test to Expand Testing Access in Low- and Middle-Income Countries
- Rapid Test Diagnoses Tropical Disease within Hours for Faster Antibiotics Treatment
- Rapid Molecular Testing Enables Faster, More Targeted Antibiotic Treatment for Pneumonia