[21] Phage display for selection of novel binding peptides

Phage display, as it is practiced today for the selection of naive peptide binders, mirrors the natural immune system. A large and diverse set of peptides can be presented in a polyvalent format. Peptides that are selected from this polyvalent format bind their target in the high micromolar range. Higher affinity peptides are generated from these leads by introducing additional mutations and transferring the pepitides onto a lower valency format to allow the selection of peptides with affinities in the low micromolar to nanomolar range. Such peptides are useful reagents: they may serve as simple probes to understand molecular recognition, they may act as minimized surrogates for known or orphaned receptors, or they may even serve as lead molecules in drug design. The technology of peptide phage display has exploded in recent years. It has the ability to generate small peptides (10–20 residues long) that will bind to almost any protein with moderate to high affinity. The technology effectively mimics the immune system and even offers some advantages.