Figure 5

Accessory cells (ACs) of immunised IFN-γR KO mice are required for their defective T_reg activity. T_reg cells, T_eff cells and ACs were isolated from lymph nodes and spleen of IFN-γR KO and wild-type DBA/1 mice 21 days after immunisation with collagen type II in complete Freund's adjuvant. Mixing experiments were performed as indicated. In each set, 5 × 10⁴ CD4⁺CD25^- T_eff cells were incubated with anti-CD3 antibody in the presence of ACs and the indicated number of CD4⁺CD25⁺ T_reg cells. The percentage inhibition of the proliferation of T_eff cells (CD4⁺CD25^-) by increasing numbers of CD4⁺CD25⁺ T_reg cells is shown. The results are representative of two independent experiments.