Biophysical characterization of antibodies with isothermal titration calorimetry

Abstract

REVIEW Antibodies play a key role in the immune response. Since antibodies bind antigens with high speciicity and tight afinity, antibodies are an important reagent in experimental biology, assay development, biomedical research and diagnostics. Monoclonal antibodies are therapeutic drugs and used for vaccine development. Antibody engineering, biophysical characterization, and structural data have provided a deeper understanding of how antibodies function, and how to make better drugs. Isothermal titration calorimetry (ITC) is a label-free binding assay, which measures afinity, stoichiometry, and binding thermodynamics for biomolecular interactions. When ther-modynamic data are used together with structural and kinetic data from other assays, a complete structure-activity-thermodynamics proile can be constructed. This review article describes ITC, and discusses several applications on how data from ITC provides insights into how antibodies function, guide antibody engineering, and aid design of new therapeutic drugs.