Fig. 4.

Adjuvant effects of CT in EPI are dependent on GM1 interactions and are enhanced by physical fusion between antigen and adjuvant. (A) B6 and GalT^−/− DKO mice were adoptively transferred with naïve OT-I cells 1 d before EPI on ear skin. Five days later, OT-I cells were detected in lymph nodes and spleen by the congeneic marker Thy1.1 in the CD3⁺ CD8⁺ population. Data are compiled from two independent experiments and similar data were obtained in an additional experiment. (B) B6 mice were adoptively transferred with naïve OT-I cells 1 d before immunization on the ear. Animals were immunized using sequential administration of free-OVA peptide, followed by either normal (column 3) or enzymatically inactive CT (CTmut) (column 4). Alternatively, mice were immunized by a single application of OVA peptide-tagged CT (column 5) or CTmut (column 6). Compilation of data from two experiments is shown, and analogous results were observed in a similar independent experiment.