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Updated: May 7, 2026
07:39
Determining Binding Affinity (KD) of Radiolabeled Antibodies to Immobilized Antigens
Published on: June 23, 2022
Bond elasticity controls molecular recognition specificity in antibody-antigen binding
Anna Alemany1, Nuria Sanvicens, Sara de Lorenzo
1Small Biosystems Lab, Department Física Fonamental, Universitat de Barcelona , C/Martí i Franquès 1, 08028 Barcelona, Spain.
Nano Letters
|October 1, 2013
Summary
Investigating antibody-antigen interactions with optical tweezers reveals bond flexibility is key. This flexibility helps remodel bonds for improved recognition in the maturing immune system.
Area of Science:
- Biophysics
- Immunology
- Molecular Mechanics
Background:
- Characterizing single ligand-receptor interactions is crucial for understanding biological recognition.
- Antibody-antigen interactions are fundamental to adaptive immunity and humoral immune system maturation.
- Force spectroscopy offers a powerful approach to probe the mechanical properties of biomolecular bonds.
Purpose of the Study:
- To quantify the spectrum of bond strengths and flexibilities in antibody-antigen interactions.
- To investigate the mechanical evolution of polyclonal antibodies post-infection.
- To assess the cross-reactivity of monoclonal antibodies against diverse antigens.
Main Methods:
- Utilizing optical tweezers to perform single-molecule force spectroscopy.
- Measuring rupture forces and unbinding kinetics of antibody-antigen complexes.
- Analyzing the mechanical properties of antibody bonds under varying conditions.
Main Results:
- A spectrum of bond strengths and flexibilities was observed in antibody-antigen interactions.
- Polyclonal antibodies showed distinct mechanical evolution patterns after infection.
- Monoclonal antibodies exhibited varying degrees of cross-reactivity against different antigens.
- Bond flexibility was identified as a significant factor in antibody-antigen bond remodeling.
Conclusions:
- Bond flexibility plays a critical role in the adaptive remodeling of antibody-antigen bonds.
- This remodeling mechanism is essential for enhancing molecular recognition during humoral immune system development.
- Optical tweezers provide valuable insights into the dynamic mechanical behavior of immune system components.
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