Profile of responding T lymphocytes primed by stimulating DCs in allogeneic reactions. iDCs or IFN-β, IFN-λ, or LPS-treated DCs were used for 24 hours to stimulate allogeneic T-cell proliferation in vitro at a 1:10 DC/T-cell ratio. [³H]-Thymidine was added for the last 18 hours of culture. (A) CD4⁺ T lymphocytes present in MLR reactions were analyzed for their expression level of CD25 by flow cytometry. (B) Percentage of CD4⁺ CD25^+hi T cells in MLR cultures. Mean ± SEM of 3 experiments performed with different blood donors. (C) Purity analysis of CD4⁺ T cells separated for the expression of CD25 by immunomagnetic selection into CD4⁺CD25^– (i) and CD4⁺CD25⁺ T cells (ii). (D) Proliferation of CD4⁺CD25⁺ or CD25^– T lymphocytes primed by DCs. Mean ± SEM of 3 independent experiments performed on different blood donors.