Determination of High-affinity Antibody-antigen Binding Kinetics Using Four Biosensor Platforms.

Area of Science:

• Biochemistry
• Biotechnology
• Drug Discovery

Background:

• Label-free optical biosensors are crucial for analyzing biomolecular interactions in drug discovery.
• Characterizing high-affinity monoclonal antibodies (mAbs) against targets like PCSK9 is vital for therapeutic development.

Purpose of the Study:

• To compare the performance of four distinct biosensor platforms in evaluating antibody-antigen binding kinetics.
• To assess the suitability of Surface Plasmon Resonance (SPR) and Bio-Layer Interferometry (BLI) technologies for kinetic characterization.

Main Methods:

• Utilized four biosensor platforms: Biacore T100 (SPR), ProteOn XPR36 (SPR), IBIS MX96 (SPR with imaging), and Octet RED384 (Bio-Layer Interferometry).
• Evaluated binding affinity and kinetics of ten high-affinity mAbs against human PCSK9 using a standardized assay format and reagents.
• Compared serial vs. parallel flow configurations (SPR) and continuous flow vs. static immersion (SPR vs. BLI).

Main Results:

• Each biosensor platform demonstrated unique advantages and disadvantages in data acquisition and throughput.
• SPR-based platforms (Biacore, ProteOn, IBIS) offered different configurations affecting throughput and detection methods.
• The Bio-Layer Interferometry (BLI) system (Octet) provided an alternative detection principle without continuous flow fluidics.

Conclusions:

• Direct comparison of biosensor platforms is essential for selecting the optimal tool for specific drug discovery needs.
• Standardized protocols and high-quality reagents are key for reliable kinetic data across different platforms.
• The study provides insights into the practical application of various label-free biosensor technologies for antibody-antigen interaction analysis.