FIG. 1.

Identification of IpaD epitopes exposed on the surface of S. flexneri. Antibodies produced in rabbits immunized with purified recombinant IpaD were affinity purified against intact, virulent S. flexneri 5 strain M90T-W. Untreated serum (before affinity purification) (stippled peaks) and affinity-purified antibodies (solid peaks) were used to probe overlapping synthetic peptides representing the entire IpaD sequence. A subset of peptide epitopes mapped in the untreated serum samples were also identified with the affinity-purified antibodies, indicating that these IpaD peptide epitopes were exposed on the surface of virulent shigellae.