Fig. 7.

Splenic CD8⁺CD25⁺ T cells in the H6F-treated NOD.β2m^null.HHD mice exerted ligand-specific suppressive activity. a Suppression of CD4⁺CD25^- T cell proliferation by splenic CD8⁺CD25⁺ T cells or CD4⁺CD25⁺ T cells. CD4⁺CD25^- T cells (100,000 cells/well) were co-cultured in triplicate with varied numbers of CD8⁺CD25⁺ (open bars) or CD4⁺CD25⁺ (gray bars) T cells isolated from the same H6F-treated mice at 1∶0, 10∶1, 5∶1, 2∶1, 1∶1 and 0∶1 ratios in the presence of anti-CD3/CD28-coupled beads for 3 days. ^*P < 0.05 and ^**P < 0.01 compared with the [³H] thymidine uptake of CD4⁺CD25^- T cells alone. b The proliferation of pre-activated CD4⁺CD25^- T cells (50,000 cells/well) cocultured with mitomycin C-treated syngeneic splenocytes (250,000 cells/well) loaded with 10 μg/ml OVA_257-264 (gray bars), 10 μg /ml H6F (open bars), or no peptide (black bar) in the presence of an equal number of CD8⁺CD25⁺ T cells purified from the spleens of H6F-treated NOD.β2m^null.HHD mice. **P < 0.01 compared with the [³H] thymidine uptake of CD4⁺CD25^- T cells cocultured with mitomycin C-treated syngeneic splenocytes alone. c IFN-γ and IL-17A in the cell culture supernatants from (b) were assayed by ELISA. ^***P < 0.001 and ^**P < 0.01 compared with IFN-γ and IL-17A in the cell culture supernatants of CD4⁺CD25^- T cells cocultured with mitomycin C-treated syngeneic splenocytes alone. The data are presented as the mean of triplicate cultures and are representative of three independent experiments. Significance was determined by an unpaired t-test