Chronic expansion of CD8 ⁺ Tconv cells follows IL-2 dysregulation despite heightened Treg representation. (A) Cellularity of spleen and LN of 4–6-wk-old CD8^creRosa^IL-2, CD4^cre Rosa^IL-2, or littermate controls. n = 12–34. (B and C) Frequency (B) and number (C) of splenic CD8⁺ Tconv, CD4⁺ Tconv, and CD4⁺ Tregs. n = 9–21. (D) Frequency of Foxp3⁺ cells among total CD4⁺ T cells. n = 9–21. (E) tSNE representation of high-parameter flow cytometry data from splenic CD4⁺ (top) and CD8⁺ (bottom) T cells. FlowSOM clusters annotated based on differential expression of key markers. D value represents cross-entropy distance between samples. (F) Correlation between clusters in E. WT:Rosa^IL-2 indicates whether correlation is higher or lower in WT relative to CD8^cre or CD4^cre Rosa^IL-2. (G) Frequency of naive, central memory (CD44^hi CD62L^hi), or effector (CD44^hi CD62L^lo) CD8⁺ Tconv. n = 6–19. (H) IFNγ expression by CD8⁺ Tconv. n = 3–12. (I) Frequency of central memory (CD44^hi CD62L^hi) or effector (CD44^hi CD62L^lo) CD4⁺ Tconv. n = 6–19. (J) Cytokine production from CD4⁺ Tconv. n = 6–32. (K) Healthy survival analysis, indicating onset of moderate symptoms. n = 5–23. Data representative of (H) or pooled from (A–G and I–K) at least two independent experiments. Significance was tested by one-way ANOVA (A and C), Kruskal–Wallis test (B and G–J), multiple Kolmogorov–Smirnov tests with Holm correction (E), or Mantel–Cox log-rank test (K).