Structural Basis of AntibodyAntigen Interactions

Antibody molecules can be regarded as products of a protein engineering system for the generation of a virtually unlimited repertoire of complementary molecular surfaces. This extreme structural heterogeneity is required for recognition of the nearly infinite array of antigenic determinants. This chapter discusses the structures of antibodies and their specific recognition of antigens, the binding energetics of these interactions, the cross-reactivity and specificity of antibody–antigen interactions, the role of conformational flexibility in antigen recognition, and the structural basis of the antibody affinity maturation process.