Fig. 2

Phenotype of the in vitro expanded Tregs. a Tregs from CTR, LT and KT patients were expanded up to 21 days with IL-2 and rapamycin. Fold expansion of day 7, 14 and 21 was calculated as compared to day 0 seeded cells. b Graph shows the percentage of Treg (CD4+CD25+CD127−FoxP3+) at each time point stimulation. Treg purity increased significantly during expansion in CTR and KT patients. c The graph shows the percentages of contaminant cells during the expansion period. The contaminant cells decreased below 1% in CTR and in LT patients and below 3% in KT patients at the end of expansion. d Viability of cryopreserved/thawed day 21 Tregs is shown. No significant difference was observed between patients and CTR (p = NS). e Phenotype of the cryopreserved/thawed day 21 Tregs is shown as mean percentages of CD4+CD25+CD127−FoxP3+ cells. The thawed Tregs were almost all FoxP3 positive in patients/CTR. No significant difference was observed between patients and controls (p = NS). Data are represented as mean ± SEM (*p < 0.05)