Tregs expanded with DCs from CTX-treated mice have less suppressor activity. Isolated CD4⁺ CD25⁺ Tregs from Balb/c mice were cocultured with different DC subsets (DCs from naive mice, DCs from CTX-treated mice, CD8⁺ DCs, and DCs from CTX-treated mice + CD8⁺ DCs) from B6 mice (primary MLR). After 7 days, Tregs expanded with different DC subsets were mixed with 10⁵ CFSE-labeled CD25⁻ CD3⁺ T cells in various ratios (2:1-32:1) and stimulated with irradiated mature DCs activated with LPS (secondary MLR). At 5 days after secondary MLR culture, T-cell proliferation was examined by measurement of CFSE dilution. Results are the mean ± SEM of triplicate wells. Data are representative of 2 independent experiments. *Statistically significant.