TCR repertoire diversity and evenness in patients receiving low-dose IL-2 and HDs. For patients, diversity measurements were assessed at baseline (W0), week 12 (W12), and 1 year (1Y). (A) Hill-based diversity values for CD4Tregs, CD4Tcons, and CD8 T cells in patients with cGVHD (n = 12) and HDs (n = 8). In HDs, CD8 T cells have lower diversity than CD4Tregs (P = .008) and CD4Tcons (P = .008). In patients, CD8 T cells have lower diversity than CD4Tregs and CD4Tcons at baseline (P ≤ .001), week 12 (P ≤ .001), and 1 year (P = .03). Diversity in CD4Tcons and CD8 T cells is similar in patients compared with HDs and does not change with IL-2 therapy. Diversity in CD4Tregs is lower in patients than in HD at baseline (P = .019) but is similar to HDs at week 12 (P = .2). (B) Hill evenness values for CD4Tregs, CD4Tcons, and CD8 T cells in patients with cGVHD and HDs. Evenness is similar between HDs and patients at baseline in CD4Tcons and CD8 T cells and does not change with IL-2 therapy. In CD4Tregs, evenness is also similar between HDs and patients at baseline. However, within patients, evenness in CD4Tregs decreases significantly from baseline to week 12 (P = .04). (A-B) Each dot represents an individual patient. Box plots depict the 75th percentile, median, and 25th percentile values; whiskers represent maximum and minimum values, except for outliers. The boxes for HD are shaded in gray. Two-sided Wilcoxon signed-rank test was used to assess significance.