Analysis of IL-10⁺ CD25^High CD4⁺ regulatory T cells in the peripheral blood from chagasic patients.

<p>Frequency of regulatory T cells and intracytoplasmic IL-10 (cIL-10) levels in CD25^High CD4⁺ cells from patients with distinct clinical forms of Chagas' disease (IND, light gray box; CARD, dark gray box) and non-infected individuals (NI, white box) following short-term in vitro stimulation of whole blood samples with <i>T. cr</i>u<i>zi</i> antigens. Baseline levels of CD25^High CD4⁺ and cIL-10⁺ T cells were obtained from control cultures (CC) maintained under the same conditions (22 h incubation at 37°C, CO₂ humidified incubator). The results are expressed in box plot format for CD25^High CD4⁺ (left panels) and cIL-10⁺ T cells (right panels). The box stretches from the lower hinge (defined as the 25^th percentile) to the upper hinge (the 75^th percentile) and, therefore, contains the middle half of the score in the distribution. The median is shown as a line across the box. Therefore, 1:4 of the distribution is between this line and the bottom or the top of the box. Significant differences are identified by connecting lines for comparisons between CC and Ag, and highlighted the ability of <i>T. cruzi</i> antigens to trigger enhanced levels of CD25^High CD4⁺ and cIL-10⁺ T cells in both IND and CARD groups. Significant differences between clinical groups are identified by asterisks as compared to NI.