Figure 1. Suppressive ODN promote the generation of iT_reg in vitro.

CD4⁺CD25⁻ T cells were isolated from female BALB/c mice by negative selection. They were incubated for 2 h with 1 uM of suppressive or control ODN and then cultured under T_reg polarizing conditions (3 ug/ml of anti-CD3, 2 ug/ml of anti-CD28 and 5 ng/ml of TGFβ) for 5 days. iT_reg were identified based on their expression of CD4 and FoxP3 by flow cytometry. B, C) Combined results from 4 independent experiments showing the frequency and absolute number of CD4⁺ FoxP3⁺ T_reg (mean + SE) generated by each type of treatment over 3–5 days. (D) mRNA was isolated after 5 days of culture and analyzed for FoxP3 gene expression by RT PCR. Relative mRNA levels were calculated by comparison to cells cultured under the same conditions in the absence of ODN. Results from each group were normalized to GAPDH mRNA levels. Each bar represents the mean + SE of 3 independent experiments.

*, p<0.05; **, p<0.01; ***, p<0.001