Figure 2.

The distinct CD4⁺ FoxP3^HI cell population in activated PBMC is generated from nTregs. (a) ‘Whole’ or ‘CD25-depleted’ (using magnetic beads; Miltenyi Biotec, Auburn, CA) PBMC were anti-CD3 activated. After 3 days, CD4⁺ T cells were analysed for CD25 and FoxP3 expression. (b) CFSE-labelled CD25^Neg cells were tested by FACS for division by CFSE dilution at day 6 or 9 of culture in anti-CD3-activated whole or CD25-depleted PBMC from (a). Numbers indicate the per cent of cells that have undergone division based on CFSE dilution. Data are representative of two separate experiments. CFSE, carboxyfluorescein succinimidyl ester; FACS, fluorescence-activated cell sorting; nTregs, natural regulatory T cells; PBMC, peripheral blood mononuclear cells.