BCL-2 Heterodimer Immunoassays for BH3 Mimetic Selection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for selecting patients for treatment with drugs targeting the apoptosis pathway, such as BH3 mimetics, are inadequate as they rely on qualitative measurements of Bcl-2 family member proteins or mRNA levels, failing to assess functional protein-protein interactions effectively.

Innovation Solution

A method for detecting Bcl-2 family heterodimeric complexes in biological samples using specific antibodies to identify the presence of complexes like BIM-Bcl-2, BIM-Bcl-xL, BIM-Mcl-1, and BAX-BAK, which involves preparing a cell lysate and using antibodies bound to a solid support to detect these complexes in the presence or absence of a drug, indicating suitability for treatment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If immunohistochemistry (IHC) is used to measure Bcl-2 family member proteins, then qualitative measurement of proteins is achieved, but measurement of protein-protein interactions is not possible

Engineering Contradiction:

Improveprotein detection capabilityVSAvoidprotein-protein interaction detection

Core Design Contradiction:

Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The detection method is segmented into multiple sequential steps: (1) capturing one Bcl-2 family protein on a solid support via antibody binding, (2) incubating with cell lysate containing potential heterodimer partners, (3) washing to remove unbound proteins, and (4) detecting the presence of heterodimeric complexes. This segmentation allows the assay to specifically measure protein-protein interactions rather than just total protein levels.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

An antibody-bound solid support acts as an intermediary to capture and immobilize one member of the Bcl-2 family (e.g., BIM, BAX) while allowing potential interaction partners (e.g., Bcl-2, Bcl-xL, Mcl-1) to bind from the cell lysate. This intermediary approach enables the detection of transient or weak protein-protein interactions that would be difficult to detect by other methods.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Loss of information

If mRNA levels are measured to screen for Bcl-2 family members, then nucleic acid sequence information is obtained, but functional protein interactions and translated protein levels are not reflected

Engineering Contradiction:

ImprovemRNA level informationVSAvoidfunctional protein interaction assessment

Core Design Contradiction:

Loss of informationVSReliability

Solution Approach 1:

The patent replaces nucleic acid-based detection methods (PCR, sequencing) with a protein-based immunoassay system. Instead of measuring mRNA transcripts, the method directly detects functional protein-protein interactions using antibody-antigen binding, thereby providing information about actual protein levels and functional interactions that cannot be inferred from mRNA data alone.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Productivity

If tumor cells are cultured in vitro and challenged with synthetic peptides, then drug effectiveness can be identified, but the complexity and time required for cell culture and drug testing increases

Engineering Contradiction:

Improvedrug screening throughputVSAvoidcell culture and drug testing system

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The assay performs preliminary detection of Bcl-2 family heterodimer composition and drug sensitivity directly in patient-derived cell lysates before committing to lengthy in vitro cell culture experiments. By measuring the baseline heterodimer status and testing drug effects on heterodimer disruption in a simplified lysate-based system, the method predicts which patients will respond to BH3 mimetics without requiring extensive cell culture validation.

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

This approach allows for the selection of drugs targeting the apoptosis pathway by quantitatively assessing protein-protein interactions, improving the accuracy of patient selection and drug efficacy prediction.

Implementation Method 1

providing an antibody specific for the first protein bound to a solid support; contacting the cell lysate with the antibody-bound solid support

Methodology Applied

Scientific EffectAntigen-antibody binding:

Implementation Method 2

providing a detection antibody specific for the second protein; detecting the presence of the detection antibody

Methodology Applied

Scientific EffectAntigen-antibody binding:

Data Source

PatentUS12631645B2Detection of BCL-2 family heterodimer complexes and use thereof

Publication Date: 2026.05.19 THE GOVERNMENT OF THE UNITED STATES OF AMERICA AS REPRESENTED BY THE SECRETARY DEPARTMENT OF HEALTH & HUMAN SERVICES

AI summary

Immunoassays to detect the presence of Bcl-2 family heterodimeric complexes are described. The immunoassays are designed to detect one or more of BIM-Bcl-2, BIM-Bcl-xL, BIM-Mcl-1 and BAX BAK heterodimers. The assays can be used, for example, to select a BH3 mimetic, or other drug targeting the apoptosis pathway, that is effective for treating a specific cancer, or to select a subject who is likely to respond to a particular BH3 mimetic.