Epitope Discovery: A New Route to Vaccines

摘要

Libraries of random peptides displayed on filamentous phage serve as rich sources of artificial epitopes that may someday be the basis of a new generation of synthetic vaccines. In order to identify peptides with potential protective value, antibodies from individuals who have been naturally or experimentally immunized against the actual pathogen are used to affinity-select binding peptides from the phage-display libraries. The selected peptides are used in turn to immunize naive individuals to see if immunity to the natural pathogen is induced. The potential of this scheme for vaccine development is being assessed using a model 'pathogen'-T4 bacteriophage-that is abundantly available and easy and safe to handle, yet preserves the essential immunological features of real pathogens. We have also constructed a new 'landscape' library, which, like the one already reported, displays a randomized patch of amino acids on all 3,900 copies of the major phage coat protein pVIII. In the new library, the randomized amino acids lie in the middle of the pVIII sequence, rather than at the N-terminus as in the first library.