FIG. 6.

Comparison of native LT, native CT, CT-A–LT-B, and LT-A–CT-B for the ability to induce antigen-specific cytokine responses in in vitro antigen restimulation assays. Splenocytes harvested from animals immunized for this experiment were cultured with naive macrophages and 10 μg of TT per well. Supernatants were collected and analyzed for the presence of IL-5 and IFN-γ by an ELISA on days 1, 3, 5, and 7. Antigen-specific cytokine levels are shown for day 5 culture supernatants. Results are representative of two independent experiments.