FIGURE 3.

Treatment of colitis in the absence of in situ-derived iT_reg cells. A, Weight change following colitis induced by adoptive transfer of 4 × 10⁵ CD4⁺EGFP⁻ Thy1.1⁺CD45RB^high T cells isolated from Foxp3^ΔEGFP mice. After 5–7% weight loss, recipients were treated by i.p. injection of 0.25 × 10⁶ Thy1.2⁺EGFP⁺ nT_reg cells (red; n = 6), by 0.5 × 10⁶ Thy1.2⁺EGFP⁺ nT_reg cells (orange; n = 6), by 1 × 10⁶ Thy1.2⁺EGFP⁺ nT_reg cells (green; n = 5), or by a mixture of 0.5 × 10⁶ Thy1.1⁺ iT_reg and 0.5 × 10⁶ Thy1.2⁺nT_reg cells (blue; n = 5). Color-matched solid lines represent the polynomial fit based on a random coefficient regression model. B, Kaplan-Meier survival curves for the mice in A. C, Representative histological sections from the colons of the mice in A stained with H&E. D, Scatter plots depicting the colitis scores for each group. E, Representative flow cytometry analysis of the mesenteric lymph nodes from mice treated with nT_reg cells (left panels) or a mixture of both cell types (right panel). Numbers denote mean values for the quadrant or gate. F, Bar graphs depicting the total number of T_reg cells found in the mesenteric lymph nodes and spleens of treated mice. The proportion of nonfunctional in situ-derived ΔiT_reg cells (black), nT_reg cells (green), and in vitro-derived iT_reg cells (pink) is indicated. ns, Not significant).