CDR3 size analysis of TCR Vβ transcripts from splenic CD8⁺T cells. CD8⁺ splenic T cells were sorted to perform CDR3 size length analysis. (A) Results of eight Vβ spectratypes among the 24 analyzed are shown for 1 representative subject in each group (control, RTX-untreated, and RTX-nonresponder ITP patients). (B) CD8⁺ T-cell TCR repertoire perturbation indexes, calculated using ISEApeaks software, are summarized in dot plots in 9 controls (black circles), 11 RTX-untreated patients (black squares), and 9 RTX nonresponders (black triangles). The horizontal bar represents the median with the interquartile range. P values were derived by Mann-Whitney U test. **P < .01. NS, nonsignificant.