Mice were immunized according to Figure 4. Sera of mice were pooled in groups and titrated against human epithelial cell adhesion molecule (EpCAM), expressing 293Ep cells and nonexpressing 293Δ cells (vector control), respectively. Cell-bound antibodies were detected by flow cytometry using a fluorescein isothiocyanate-conjugated goat antimouse immunoglobulin G1 antibody.

Data reflect serum dilutions at which percentage of positively stained cells was still 3 times above background reaction with control sera (serum pool before immunization).