Upon priming with BLG, cord blood derived CD4⁺CD25⁺ T cells become highly suppressive.

<p>(<b>A</b>) Cord blood-derived mononuclear cells were co-cultured for 6 days with the antigen BLG. At day six CD4⁺CD25⁺ T cells were MACS-sorted and an inhibition assay was performed with the CD4⁺CD25⁻ (frozen on day 0, without prior antigen exposure) and stimulated with α-CD3 or BLG. The inhibitory potential is expressed as relative proliferation compared to the CD4⁺CD25⁻ cells. Results are representative for 6–9 independent experiments. Wilcoxon signed rank test was applied. P-values of less than 0.05 were considered significant (*); p<0.005 (**); p<0.001 (***). (<b>B</b>) Real-time PCR analysis was performed to quantify the gene expression of Treg-related markers (FOXP3, GARP, RUNX 1, and RUNX 3) after allergen exposure. Results are representative for three independent experiments showing the normalized expression. CD4⁺CD25⁻ T cells are displayed with white and CD4⁺CD25⁺ T cells with black squares.