B Cell Epitope Mapping Using Synthetic Peptides

Synthetic peptides are used for identification of functional B cell epitopes in antibody preparations. ELISA-type assays are used to identify sequences of proteins comprising antibody-binding regions. This unit describes three peptide display formats. Pepscan (pins) and SPOTs (cellulose membranes) may be used as solid-phase support media for peptide synthesis, followed by ELISA directly on the resulting peptide array. Alternatively, peptides may be cleaved from the array and tested in a standard microplate-based antibody capture ELISA format. The discussion includes choosing the peptide sequences by length and overlap, as well as determination of the minimum essential sequence for antibody binding. This method is highly effective for continuous epitopes and is often also useful for discontinuous epitopes.