Engineered affibodies in translational medicine

Abstract

Affibody proteins are an emerging class of small protein (7 kDa) scaffold-based affinity reagents. Affibodies were first reported 10 years ago and have since been developed to bind to several important biomarkers. Affibody proteins were originally produced from staphylococcal protein A, and later, they are selected from phage display libraries based on a 58 amino acid and three alpha-helical Z-domain scaffolds. They can be reliable produced by both conventional peptide synthesis chemistry and recombinant expression in Escherichia coli. Protein engineering techniques have been used to make Affibody molecules bind to a target specifically and meet the requirement such as high affinity, high uptake, and high contrast imposed by intended application. General structures and engineering strategies to optimize Affibody molecules for diagnostic imaging and therapy applications are described in this book chapter. The current research on using Affibody molecules for molecular imaging and therapy is also discussed.