Measurement of telomere length in Tcon and Treg. Tcon and Treg were purified by cell sorting, and DNA from each population was isolated and used as a template for quantitative real-time PCR for telomere length measurement. Relative telomere length indicates the average T/S of each sample described in “Measurement of telomerase length.” All samples were measured in triplicate. Box plots indicate the values for median, 25th and 75th percentile; whiskers, outer part of distribution; and outside dots, individual outliers. At the time of sample analysis, 13 patients had no cGVHD, 20 had mild cGVHD, 16 had moderate cGVHD, and 12 had severe cGVHD. Samples were also obtained from 19 adult healthy subjects (HS). (A) Telomere length of Tcon and Treg in healthy subjects and patients after HSCT. P values indicate comparisons for each category. (B) Telomere length of Tcon in healthy subjects and patient subsets based on severity of cGVHD. P values indicate comparisons among patient subsets. (C) Telomere length of Treg in healthy subjects and patient subsets based on severity of cGVHD. P values indicate comparisons among patient subsets. N.S. indicates not significant.