Mutated HEV Polypeptide p-ORF2-MUT for Diagnostic Sensitivity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current diagnostic methods for hepatitis E virus (HEV) infections face challenges due to the short period of viremia and the need for expensive equipment, as well as limitations in the presentation of conformational epitopes using recombinant polypeptides like 394-660, which can inhibit self-assembly and reduce sensitivity.

Innovation Solution

A mutated polypeptide, p-ORF2-MUT, is developed with improved antigenicity and immunoreactivity by modifying the sequence at positions 627, 630, and 638, allowing for natural dimerization and oligomerization without aggregation, enhancing diagnostic specificity and sensitivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If recombinant polypeptide 394-660 is used for HEV detection, then the diagnostic tool is available, but the sensitivity is reduced due to inhibition of self-assembly and poor presentation of conformational epitopes

Engineering Contradiction:
Improvediagnostic sensitivityVSAvoidepitope presentation
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent applies parameter changes by modifying the amino acid sequence of the polypeptide at specific positions (627, 630, and 638) to eliminate inhibition of self-assembly. These mutations enable the polypeptide to properly fold and present conformational epitopes, thereby improving both diagnostic sensitivity and reliability simultaneously.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If current diagnostic methods are used, then HEV detection is possible, but expensive equipment is required

Engineering Contradiction:
Improvedetection capabilityVSAvoidequipment requirement
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent employs a recombinant polypeptide-based immunoassay that can be performed using standard laboratory equipment without requiring expensive specialized instruments. The mutated polypeptide serves as a stable, reusable reagent that enables sensitive HEV detection through conventional immunoassay techniques, eliminating the need for costly equipment while maintaining detection capability.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Duration of action of moving object

If viremia period is short, then HEV infection is transient, but detection window is limited

Engineering Contradiction:
Improveviremia durationVSAvoiddetection window
Core Design Contradiction:
Duration of action of moving objectVSMeasurement precision

Solution Approach 1:

The patent detects HEV infection by identifying antibodies produced during the viremic phase rather than detecting the virus itself. The mutated polypeptide 394-660 serves as an antigen that binds to HEV-specific antibodies, allowing detection to occur during the limited viremia window when antibodies are being produced, thereby maximizing the detection opportunity despite the short duration of viremia.

Inventive Principle:
Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The mutated polypeptide, p-ORF2-MUT, increases diagnostic specificity and maintains sensitivity, providing a more reliable and efficient tool for detecting HEV infections without the drawbacks of previous recombinant polypeptides.

Implementation Method 1

The mutated polypeptide, p-ORF2-MUT, increases diagnostic specificity and maintains sensitivity, providing a more reliable and efficient tool for detecting HEV infections

Methodology Applied
Scientific EffectAntigen-antibody binding:

Data Source

PatentEP3383887B1Mutated hev polypeptides and the use thereof for assaying Anti-hev antibodies
Publication Date: 2022.03.16 BIOMERIEUX SA
  • EP3383887B1 patent drawingFigure 1A
  • EP3383887B1 patent drawingFigure 1B
  • EP3383887B1 patent drawingFigure 1C

AI summary

The present invention relates to polypeptides of the ORF2 protein of the hepatitis E virus including at least the amino acid sequence 394-660, numbered in relation to an ORF2 protein of 660 amino acids, in which three cysteines at positions 627, 630 and 638 have been mutated or, for an ORF2 protein of different length, at least the amino acid sequence corresponding to amino acids 394-660 of the ORF2 protein of 660 amino acids, in which the three cysteines located at the three positions corresponding to positions 627, 630 and 638 of the ORF2 protein of 660 amino acids have been mutated. The invention also relates to methods for determining the presence of the humoral response or the number of antibodies directed against the ORF2 protein using these polypeptides, as well as the use thereof in the context of infection with the hepatitis E virus. No figure