EFFICIENT EPITOPE MAPPING BY BACTERIOPHAGE-LAMBDA SURFACE DISPLAY

A bacteriophage lambda surface expression system, lambda foo, was used for epitope mapping of human galectin-3. We constructed random epitop e and peptide libraries and compared their efficiencies in the mapping , The galectin-3 cDNA was randomly digested by DNase I to make random epitope libraries, The libraries were screened by affinity selection u sing a microtiter plate coated with monoclonal antibodies. Direct DNA sequencing of the selected clones defined two distinct epitope sites c onsisting of nine and 11 amino-acid residues. Affinity selection of ra ndom peptide libraries recovered a number of sequences that were simil ar to each other but distinct from the galectin-3 sequence, These resu lts demonstrate that a single affinity selection of epitope libraries with antibodies is able to define an epitope determinant as small as n ine residues long and is more efficient in epitope mapping than random peptide libraries.