Figure 5.

mIL-2/CD25 enhances trafficking of Tregs into lymphoid tissues and the pancreas of NOD.SCID mice. Seven- to 8-week-old female CD45.2⁺ NOD mice received a single injection of mIL-2/CD25 (10 μg) or HBSS. Forty-eight hours later, unfractionated spleen cells (3 × 10⁷ cells) were transferred i.v. into 6- to 7-week-old female CD45.1⁺ NOD.SCID mice, and their spleen, MLN, and pancreas were analyzed 24–28 h posttransfer for donor T cells. A: Experimental flowchart and representative FACS gating. B: Distribution of T cells in the donor inoculum. Enumerated are total CD4⁺ T cells, the fraction of Tregs in CD4⁺ T cells, and CD8⁺ T cells, including their expression of CD25 and Ki67. Data represent two pools of donor cells, are shown as mean ± range, and were analyzed by an unpaired two-sided t test. C–E: Distribution of CD45.2-donor–derived T cells in recipient NOD.SCID mice. Enumerated are CD4⁺Foxp3⁻ T cells (C), CD8⁺ T cells (D), and CD4⁺Foxp3⁺ Tregs (E), including their expression of CD25 and Ki67, from the indicated tissues. C–E: Data (n = 5/group) are combined from two independent experiments, are shown as mean ± SEM, and were analyzed by an unpaired two-sided t test. *P ≤ 0.05; **P ≤ 0.01. hrs, hours; MFI, mean fluorescence intensity.