Cytokine production of allospecific CD4⁺ T cells. Purified CD3⁺ T cells were stimulated with allogeneic OCs or LPS-stimulated OCs for 6 days. DCs were used as control. After the culture, CD4⁺ T cells were sorted out and restimulated with anti-CD3 and anti-CD28 antibodies for 24 hours. Supernatants were collected and the concentrations of IFN-γ, IL-10, IL-4, and TGF-β1 were measured by ELISA. (A) Production of cytokines by CD4⁺ T cells stimulated by OCs. (B) Production of cytokines by CD4⁺ T cells stimulated by DCs. Representative results from 2 independent experiments are shown.