Global multi-method analysis of interaction parameters for reversibly self-associating macromolecules at high...

Area of Science:

• Biophysics
• Colloidal Chemistry
• Protein Science

Background:

• Weak macromolecular interactions are crucial in concentrated solutions, impacting fields from cell biology to drug manufacturing.
• Biophysical techniques measure these interactions via coefficients, but protein self-association complicates results, leading to inconsistent data.
• Existing methods struggle to reconcile data from different techniques when proteins exhibit reversible self-association.

Purpose of the Study:

• To develop a global multi-method analysis to accurately characterize macromolecular interactions in concentrated solutions.
• To create a self-consistent framework that deconvolutes nonideality coefficients from self-association properties.
• To enable reliable quantitative interpretation of nonideality coefficients for probing dynamics in concentrated protein solutions.

Main Methods:

• Global multi-method analysis integrating orthogonal biophysical techniques.
• Application to monoclonal antibodies with varying self-association degrees.
• Simultaneous analysis of static and dynamic light scattering (SLS, DLS) and sedimentation velocity (SV) data.

Main Results:

• Successfully demonstrated a synergistic approach bridging resolution and sensitivity gaps of individual techniques.
• Showcased a self-consistent framework capable of separating nonideality coefficients from self-association behavior.
• Achieved consistent interpretation of concentration-dependent behavior for monoclonal antibodies.

Conclusions:

• The developed method accurately quantifies weak macromolecular interactions in highly concentrated protein solutions.
• This approach resolves inconsistencies arising from protein self-association, enhancing data reliability.
• Enables advanced quantitative analysis of nonideality coefficients to study solution dynamics.