BMMCs create an optimal cytokine milieu for differentiation of Th17 cells. (A) Teffs were activated alone or in the presence of Tregs, and IgE-Ag–activated BMMCs were added or not to the T-cell culture. After 72 hours, supernatants were collected and analyzed for cytokine production. Among all cytokines analyzed, those showing significant variation between different groups are shown. *P < .05, compared with the corresponding condition in the absence of BMMCs. (B) CD45.2 Teffs and CD45.1 congenic Tregs were cultured alone or with unstimulated, IgE-sensitized, or IgE-Ag–activated BMMCs in equal amounts. After 72 hours, intracellular IL-17 content was evaluated by flow cytometry in each T-cell subset, gated according to the respective CD45 variant. Data are from 1 representative of 2 (A) or 3 (B) independent experiments.