Antigen Discovery Using Whole-Genome Phage Display Libraries

In the last two decades phage display technology has been used for investigating complex biological processes and isolating molecules of practical value in several applications. Bacteriophage lambda, representing a classical cloning and expression system, has also been exploited for generating display libraries of small peptides and protein domains. More recently, large cDNA and whole-genome lambda-display libraries of human pathogens have been generated for the discovery of new antigens for biomedical applications. Here, we describe the construction of a whole-genome library of a common pathogen—Streptococcus pneumoniae —and the use of this library for the molecular dissection of the human B-cell response against bacterial infection and colonization.