FIG. 3.

CD4⁺ T and CD8⁺ T cells are involved in the Omp31-specific cytotoxic activity elicited by pCIOmp31 or H38 immunization. 51Cr release CTL assay was undertaken as described for Fig. 2. Effector cells from pCIOmp31- or H38-immunized mice were previously incubated for 2 h with culture supernatants from anti-mouse CD4⁺ or anti-mouse CD8⁺ hybridomas or an IgG isotype control (-). The effector/target cell ratio was 100:1. Each value represents the mean ± SD of the responses of spleen cells from five individual mice. Data are representative of two separate experiments. ★, significantly different from isotype control-treated cells (P < 0.05).