aGVHD delays the recovery of the thymic output. Number of sjTREC was measured by quantitative PCR before and 3, 6, 12, and 24 months after transplantation in the PBMCs of patients with (, plain gray lines) or without aGVHD (●, dotted black lines). Mean ± SE sjTREC/150 000 PBMC (A) or total number of sjTREC/blood mm³ (B) was represented. *P < .05; ** P < .01.