Fig. 2: IL-2-self-sufficient Treg survival in mice.

A Dynamics of injected cells in the blood. Six- to twenty-week-old B6 Thy1.2 mice received 9 × 10⁵ transduced unsorted Ctrl Tregs (green line), Tregs-IL2wt (red line) or Tregs-IL2pa (blue line) in a representative experiment, n = 2 per group. B Proportion of injected cells among CD3⁺CD4⁺ cells on days 14 and 36 post-injection in four independent experiments with Ctrl Tregs (n = 8), Tregs-IL2wt (n = 5) and Tregs-IL2pa (n = 11). Statistically significant difference was found between Ctrl Tregs and Tregs-IL2pa on day 14 (p = 0.007). C Proportion of transduced cells monitored as Thy1.2⁺ among Thy1.1⁺ in injected cells (n = 2). D Treg phenotype analysis of CD25⁺Foxp3⁺ expression among injected cells (n = 2). E Endogenous CD4 Tregs, F endogenous CD4 conventional T cells (Tconv), G natural killer (NK) cells among the endogenous cells, tracked in the blood (n = 2). H Injected cell counts and zebra plots from spleen, lungs, and liver stained 14 days post-injection. I Pseudocolor plots of endogenous CD4 Tregs and Tconv from spleen, lungs, and liver 14 days post-injection. J Dynamics of injected Tregs and K endogenous CD4 Tregs in mice receiving either 9 × 10⁵ or 1 x 10⁵ Tregs-IL2pa, n = 2 per group. L Blood transfers from a primary Tregs-IL2pa recipient mouse to secondary unmanipulated recipient mice (n = 3), each receiving 250 μL of blood collected 10-11 months post-injection. Injected Tregs (top panel) and endogenous Tregs (bottom panel) were tracked in the blood of the recipient mice. Schematic created in BioRender⁴⁹. M Depletion of injected cells using an anti-Thy1.1 antibody. Data are presented as mean ± SEM in the panels (A–G) and (J–L). Data are compared using a two-tailed Mann-Whitney test in panel B (*p < 0.05; **p < 0.01; ***p < 0.001, ****p < 0.0001).